diff --git a/lib/rules/accessor-pairs.js b/lib/rules/accessor-pairs.js
index b01b29b1763..51ac2c2183a 100644
--- a/lib/rules/accessor-pairs.js
+++ b/lib/rules/accessor-pairs.js
@@ -89,7 +89,11 @@ module.exports = {
                 }
             },
             additionalProperties: false
-        }]
+        }],
+        messages: {
+            getter: "Getter is not present.",
+            setter: "Setter is not present."
+        }
     },
     create(context) {
         const config = context.options[0] || {};
@@ -140,9 +144,9 @@ module.exports = {
             }
 
             if (checkSetWithoutGet && isSetPresent && !isGetPresent) {
-                context.report({ node, message: "Getter is not present." });
+                context.report({ node, messageId: "getter" });
             } else if (checkGetWithoutSet && isGetPresent && !isSetPresent) {
-                context.report({ node, message: "Setter is not present." });
+                context.report({ node, messageId: "setter" });
             }
         }
 
diff --git a/lib/rules/array-bracket-newline.js b/lib/rules/array-bracket-newline.js
index b939d65b3f1..e1904057265 100644
--- a/lib/rules/array-bracket-newline.js
+++ b/lib/rules/array-bracket-newline.js
@@ -41,7 +41,13 @@ module.exports = {
                     }
                 ]
             }
-        ]
+        ],
+        messages: {
+            unexpectedOpeningLinebreak: "There should be no linebreak after '['.",
+            unexpectedClosingLinebreak: "There should be no linebreak before ']'.",
+            missingOpeningLinebreak: "A linebreak is required after '['.",
+            missingClosingLinebreak: "A linebreak is required before ']'."
+        }
     },
 
     create(context) {
@@ -106,7 +112,7 @@ module.exports = {
             context.report({
                 node,
                 loc: token.loc,
-                message: "There should be no linebreak after '['.",
+                messageId: "unexpectedOpeningLinebreak",
                 fix(fixer) {
                     const nextToken = sourceCode.getTokenAfter(token, { includeComments: true });
 
@@ -129,7 +135,7 @@ module.exports = {
             context.report({
                 node,
                 loc: token.loc,
-                message: "There should be no linebreak before ']'.",
+                messageId: "unexpectedClosingLinebreak",
                 fix(fixer) {
                     const previousToken = sourceCode.getTokenBefore(token, { includeComments: true });
 
@@ -152,7 +158,7 @@ module.exports = {
             context.report({
                 node,
                 loc: token.loc,
-                message: "A linebreak is required after '['.",
+                messageId: "missingOpeningLinebreak",
                 fix(fixer) {
                     return fixer.insertTextAfter(token, "\n");
                 }
@@ -169,7 +175,7 @@ module.exports = {
             context.report({
                 node,
                 loc: token.loc,
-                message: "A linebreak is required before ']'.",
+                messageId: "missingClosingLinebreak",
                 fix(fixer) {
                     return fixer.insertTextBefore(token, "\n");
                 }
diff --git a/lib/rules/array-bracket-spacing.js b/lib/rules/array-bracket-spacing.js
index 933458a42a1..c64ff3dc27e 100644
--- a/lib/rules/array-bracket-spacing.js
+++ b/lib/rules/array-bracket-spacing.js
@@ -38,7 +38,13 @@ module.exports = {
                 },
                 additionalProperties: false
             }
-        ]
+        ],
+        messages: {
+            unexpectedSpaceAfter: "There should be no space after '{{tokenValue}}'.",
+            unexpectedSpaceBefore: "There should be no space before '{{tokenValue}}'.",
+            missingSpaceAfter: "A space is required after '{{tokenValue}}'.",
+            missingSpaceBefore: "A space is required before '{{tokenValue}}'."
+        }
     },
     create(context) {
         const spaced = context.options[0] === "always",
@@ -76,7 +82,7 @@ module.exports = {
             context.report({
                 node,
                 loc: token.loc.start,
-                message: "There should be no space after '{{tokenValue}}'.",
+                messageId: "unexpectedSpaceAfter",
                 data: {
                     tokenValue: token.value
                 },
@@ -98,7 +104,7 @@ module.exports = {
             context.report({
                 node,
                 loc: token.loc.start,
-                message: "There should be no space before '{{tokenValue}}'.",
+                messageId: "unexpectedSpaceBefore",
                 data: {
                     tokenValue: token.value
                 },
@@ -120,7 +126,7 @@ module.exports = {
             context.report({
                 node,
                 loc: token.loc.start,
-                message: "A space is required after '{{tokenValue}}'.",
+                messageId: "missingSpaceAfter",
                 data: {
                     tokenValue: token.value
                 },
@@ -140,7 +146,7 @@ module.exports = {
             context.report({
                 node,
                 loc: token.loc.start,
-                message: "A space is required before '{{tokenValue}}'.",
+                messageId: "missingSpaceBefore",
                 data: {
                     tokenValue: token.value
                 },
diff --git a/lib/rules/array-callback-return.js b/lib/rules/array-callback-return.js
index 69655481d80..ad0d02697f1 100644
--- a/lib/rules/array-callback-return.js
+++ b/lib/rules/array-callback-return.js
@@ -156,7 +156,13 @@ module.exports = {
                 },
                 additionalProperties: false
             }
-        ]
+        ],
+
+        messages: {
+            expectedAtEnd: "Expected to return a value at the end of {{name}}.",
+            expectedInside: "Expected to return a value in {{name}}.",
+            expectedReturnValue: "{{name}} expected a return value."
+        }
     },
 
     create(context) {
@@ -188,9 +194,9 @@ module.exports = {
                 context.report({
                     node,
                     loc: getLocation(node, context.getSourceCode()).loc.start,
-                    message: funcInfo.hasReturn
-                        ? "Expected to return a value at the end of {{name}}."
-                        : "Expected to return a value in {{name}}.",
+                    messageId: funcInfo.hasReturn
+                        ? "expectedAtEnd"
+                        : "expectedInside",
                     data: {
                         name: astUtils.getFunctionNameWithKind(funcInfo.node)
                     }
@@ -230,7 +236,7 @@ module.exports = {
                     if (!options.allowImplicit && !node.argument) {
                         context.report({
                             node,
-                            message: "{{name}} expected a return value.",
+                            messageId: "expectedReturnValue",
                             data: {
                                 name: lodash.upperFirst(astUtils.getFunctionNameWithKind(funcInfo.node))
                             }
diff --git a/lib/rules/array-element-newline.js b/lib/rules/array-element-newline.js
index 22352c7e33d..d8a8652dbe0 100644
--- a/lib/rules/array-element-newline.js
+++ b/lib/rules/array-element-newline.js
@@ -41,7 +41,12 @@ module.exports = {
                     }
                 ]
             }
-        ]
+        ],
+
+        messages: {
+            unexpectedLineBreak: "There should be no linebreak here.",
+            missingLineBreak: "There should be a linebreak after this element."
+        }
     },
 
     create(context) {
@@ -100,7 +105,7 @@ module.exports = {
                     start: tokenBefore.loc.end,
                     end: token.loc.start
                 },
-                message: "There should be no linebreak here.",
+                messageId: "unexpectedLineBreak",
                 fix(fixer) {
                     if (astUtils.isCommentToken(tokenBefore)) {
                         return null;
@@ -149,7 +154,7 @@ module.exports = {
                     start: tokenBefore.loc.end,
                     end: token.loc.start
                 },
-                message: "There should be a linebreak after this element.",
+                messageId: "missingLineBreak",
                 fix(fixer) {
                     return fixer.replaceTextRange([tokenBefore.range[1], token.range[0]], "\n");
                 }
diff --git a/lib/rules/arrow-body-style.js b/lib/rules/arrow-body-style.js
index afbf46fd545..1f0d1377b5e 100644
--- a/lib/rules/arrow-body-style.js
+++ b/lib/rules/arrow-body-style.js
@@ -55,7 +55,15 @@ module.exports = {
             ]
         },
 
-        fixable: "code"
+        fixable: "code",
+
+        messages: {
+            unexpectedOtherBlock: "Unexpected block statement surrounding arrow body.",
+            unexpectedEmptyBlock: "Unexpected block statement surrounding arrow body; put a value of `undefined` immediately after the `=>`.",
+            unexpectedObjectBlock: "Unexpected block statement surrounding arrow body; parenthesize the returned value and move it immediately after the `=>`.",
+            unexpectedSingleBlock: "Unexpected block statement surrounding arrow body; move the returned value immediately after the `=>`.",
+            expectedBlock: "Expected block statement surrounding arrow body."
+        }
     },
 
     create(context) {
@@ -110,22 +118,22 @@ module.exports = {
                 }
 
                 if (never || asNeeded && blockBody[0].type === "ReturnStatement") {
-                    let message;
+                    let messageId;
 
                     if (blockBody.length === 0) {
-                        message = "Unexpected block statement surrounding arrow body; put a value of `undefined` immediately after the `=>`.";
+                        messageId = "unexpectedEmptyBlock";
                     } else if (blockBody.length > 1) {
-                        message = "Unexpected block statement surrounding arrow body.";
+                        messageId = "unexpectedOtherBlock";
                     } else if (astUtils.isOpeningBraceToken(sourceCode.getFirstToken(blockBody[0], { skip: 1 }))) {
-                        message = "Unexpected block statement surrounding arrow body; parenthesize the returned value and move it immediately after the `=>`.";
+                        messageId = "unexpectedObjectBlock";
                     } else {
-                        message = "Unexpected block statement surrounding arrow body; move the returned value immediately after the `=>`.";
+                        messageId = "unexpectedSingleBlock";
                     }
 
                     context.report({
                         node,
                         loc: arrowBody.loc.start,
-                        message,
+                        messageId,
                         fix(fixer) {
                             const fixes = [];
 
@@ -190,7 +198,7 @@ module.exports = {
                     context.report({
                         node,
                         loc: arrowBody.loc.start,
-                        message: "Expected block statement surrounding arrow body.",
+                        messageId: "expectedBlock",
                         fix(fixer) {
                             const fixes = [];
                             const arrowToken = sourceCode.getTokenBefore(arrowBody, astUtils.isArrowToken);
diff --git a/lib/rules/arrow-parens.js b/lib/rules/arrow-parens.js
index 5a0fd61b348..8cabb7f90f2 100644
--- a/lib/rules/arrow-parens.js
+++ b/lib/rules/arrow-parens.js
@@ -38,15 +38,19 @@ module.exports = {
                 },
                 additionalProperties: false
             }
-        ]
+        ],
+
+        messages: {
+            unexpectedParens: "Unexpected parentheses around single function argument.",
+            expectedParens: "Expected parentheses around arrow function argument.",
+
+            unexpectedParensInline: "Unexpected parentheses around single function argument having a body with no curly braces.",
+            expectedParensBlock: "Expected parentheses around arrow function argument having a body with curly braces."
+        }
     },
 
     create(context) {
-        const message = "Expected parentheses around arrow function argument.";
-        const asNeededMessage = "Unexpected parentheses around single function argument.";
         const asNeeded = context.options[0] === "as-needed";
-        const requireForBlockBodyMessage = "Unexpected parentheses around single function argument having a body with no curly braces";
-        const requireForBlockBodyNoParensMessage = "Expected parentheses around arrow function argument having a body with curly braces.";
         const requireForBlockBody = asNeeded && context.options[1] && context.options[1].requireForBlockBody === true;
 
         const sourceCode = context.getSourceCode();
@@ -94,7 +98,7 @@ module.exports = {
                 if (astUtils.isOpeningParenToken(firstTokenOfParam)) {
                     context.report({
                         node,
-                        message: requireForBlockBodyMessage,
+                        messageId: "unexpectedParensInline",
                         fix: fixParamsWithParenthesis
                     });
                 }
@@ -108,7 +112,7 @@ module.exports = {
                 if (!astUtils.isOpeningParenToken(firstTokenOfParam)) {
                     context.report({
                         node,
-                        message: requireForBlockBodyNoParensMessage,
+                        messageId: "expectedParensBlock",
                         fix(fixer) {
                             return fixer.replaceText(firstTokenOfParam, `(${firstTokenOfParam.value})`);
                         }
@@ -127,7 +131,7 @@ module.exports = {
                 if (astUtils.isOpeningParenToken(firstTokenOfParam)) {
                     context.report({
                         node,
-                        message: asNeededMessage,
+                        messageId: "unexpectedParens",
                         fix: fixParamsWithParenthesis
                     });
                 }
@@ -141,7 +145,7 @@ module.exports = {
                 if (after.value !== ")") {
                     context.report({
                         node,
-                        message,
+                        messageId: "expectedParens",
                         fix(fixer) {
                             return fixer.replaceText(firstTokenOfParam, `(${firstTokenOfParam.value})`);
                         }
diff --git a/lib/rules/arrow-spacing.js b/lib/rules/arrow-spacing.js
index d2c5b9b77bf..52f8fcab97a 100644
--- a/lib/rules/arrow-spacing.js
+++ b/lib/rules/arrow-spacing.js
@@ -38,7 +38,15 @@ module.exports = {
                 },
                 additionalProperties: false
             }
-        ]
+        ],
+
+        messages: {
+            expectedBefore: "Missing space before =>.",
+            unexpectedBefore: "Unexpected space before =>.",
+
+            expectedAfter: "Missing space after =>.",
+            unexpectedAfter: "Unexpected space after =>."
+        }
     },
 
     create(context) {
@@ -96,7 +104,7 @@ module.exports = {
                 if (countSpace.before === 0) {
                     context.report({
                         node: tokens.before,
-                        message: "Missing space before =>.",
+                        messageId: "expectedBefore",
                         fix(fixer) {
                             return fixer.insertTextBefore(tokens.arrow, " ");
                         }
@@ -108,7 +116,7 @@ module.exports = {
                 if (countSpace.before > 0) {
                     context.report({
                         node: tokens.before,
-                        message: "Unexpected space before =>.",
+                        messageId: "unexpectedBefore",
                         fix(fixer) {
                             return fixer.removeRange([tokens.before.range[1], tokens.arrow.range[0]]);
                         }
@@ -122,7 +130,7 @@ module.exports = {
                 if (countSpace.after === 0) {
                     context.report({
                         node: tokens.after,
-                        message: "Missing space after =>.",
+                        messageId: "expectedAfter",
                         fix(fixer) {
                             return fixer.insertTextAfter(tokens.arrow, " ");
                         }
@@ -134,7 +142,7 @@ module.exports = {
                 if (countSpace.after > 0) {
                     context.report({
                         node: tokens.after,
-                        message: "Unexpected space after =>.",
+                        messageId: "unexpectedAfter",
                         fix(fixer) {
                             return fixer.removeRange([tokens.arrow.range[1], tokens.after.range[0]]);
                         }
diff --git a/lib/rules/block-scoped-var.js b/lib/rules/block-scoped-var.js
index 58cef1741a8..1000fbc83c6 100644
--- a/lib/rules/block-scoped-var.js
+++ b/lib/rules/block-scoped-var.js
@@ -17,7 +17,11 @@ module.exports = {
             url: "https://eslint.org/docs/rules/block-scoped-var"
         },
 
-        schema: []
+        schema: [],
+
+        messages: {
+            outOfScope: "'{{name}}' used outside of binding context."
+        }
     },
 
     create(context) {
@@ -48,7 +52,7 @@ module.exports = {
         function report(reference) {
             const identifier = reference.identifier;
 
-            context.report({ node: identifier, message: "'{{name}}' used outside of binding context.", data: { name: identifier.name } });
+            context.report({ node: identifier, messageId: "outOfScope", data: { name: identifier.name } });
         }
 
         /**
diff --git a/lib/rules/block-spacing.js b/lib/rules/block-spacing.js
index 4fbf6d4c0bf..536381362a0 100644
--- a/lib/rules/block-spacing.js
+++ b/lib/rules/block-spacing.js
@@ -24,12 +24,17 @@ module.exports = {
 
         schema: [
             { enum: ["always", "never"] }
-        ]
+        ],
+
+        messages: {
+            missing: "Requires a space {{location}} '{{token}}'",
+            extra: "Unexpected space(s) {{location}} '{{token}}'"
+        }
     },
 
     create(context) {
         const always = (context.options[0] !== "never"),
-            message = always ? "Requires a space" : "Unexpected space(s)",
+            messageId = always ? "missing" : "extra",
             sourceCode = context.getSourceCode();
 
         /**
@@ -98,9 +103,10 @@ module.exports = {
                 context.report({
                     node,
                     loc: openBrace.loc.start,
-                    message: "{{message}} after '{'.",
+                    messageId,
                     data: {
-                        message
+                        location: "after",
+                        token: openBrace.value
                     },
                     fix(fixer) {
                         if (always) {
@@ -115,9 +121,10 @@ module.exports = {
                 context.report({
                     node,
                     loc: closeBrace.loc.start,
-                    message: "{{message}} before '}'.",
+                    messageId,
                     data: {
-                        message
+                        location: "before",
+                        token: closeBrace.value
                     },
                     fix(fixer) {
                         if (always) {
diff --git a/lib/rules/brace-style.js b/lib/rules/brace-style.js
index bc0ddbd78f2..e2cbafe2192 100644
--- a/lib/rules/brace-style.js
+++ b/lib/rules/brace-style.js
@@ -35,7 +35,16 @@ module.exports = {
             }
         ],
 
-        fixable: "whitespace"
+        fixable: "whitespace",
+
+        messages: {
+            nextLineOpen: "Opening curly brace does not appear on the same line as controlling statement.",
+            sameLineOpen: "Opening curly brace appears on the same line as controlling statement.",
+            blockSameLine: "Statement inside of curly braces should be on next line.",
+            nextLineClose: "Closing curly brace does not appear on the same line as the subsequent block.",
+            singleLineClose: "Closing curly brace should be on the same line as opening curly brace or on the line after the previous block.",
+            sameLineClose: "Closing curly brace appears on the same line as the subsequent block."
+        }
     },
 
     create(context) {
@@ -43,13 +52,6 @@ module.exports = {
             params = context.options[1] || {},
             sourceCode = context.getSourceCode();
 
-        const OPEN_MESSAGE = "Opening curly brace does not appear on the same line as controlling statement.",
-            OPEN_MESSAGE_ALLMAN = "Opening curly brace appears on the same line as controlling statement.",
-            BODY_MESSAGE = "Statement inside of curly braces should be on next line.",
-            CLOSE_MESSAGE = "Closing curly brace does not appear on the same line as the subsequent block.",
-            CLOSE_MESSAGE_SINGLE = "Closing curly brace should be on the same line as opening curly brace or on the line after the previous block.",
-            CLOSE_MESSAGE_STROUSTRUP_ALLMAN = "Closing curly brace appears on the same line as the subsequent block.";
-
         //--------------------------------------------------------------------------
         // Helpers
         //--------------------------------------------------------------------------
@@ -86,7 +88,7 @@ module.exports = {
             if (style !== "allman" && !astUtils.isTokenOnSameLine(tokenBeforeOpeningCurly, openingCurly)) {
                 context.report({
                     node: openingCurly,
-                    message: OPEN_MESSAGE,
+                    messageId: "nextLineOpen",
                     fix: removeNewlineBetween(tokenBeforeOpeningCurly, openingCurly)
                 });
             }
@@ -94,7 +96,7 @@ module.exports = {
             if (style === "allman" && astUtils.isTokenOnSameLine(tokenBeforeOpeningCurly, openingCurly) && !singleLineException) {
                 context.report({
                     node: openingCurly,
-                    message: OPEN_MESSAGE_ALLMAN,
+                    messageId: "sameLineOpen",
                     fix: fixer => fixer.insertTextBefore(openingCurly, "\n")
                 });
             }
@@ -102,7 +104,7 @@ module.exports = {
             if (astUtils.isTokenOnSameLine(openingCurly, tokenAfterOpeningCurly) && tokenAfterOpeningCurly !== closingCurly && !singleLineException) {
                 context.report({
                     node: openingCurly,
-                    message: BODY_MESSAGE,
+                    messageId: "blockSameLine",
                     fix: fixer => fixer.insertTextAfter(openingCurly, "\n")
                 });
             }
@@ -110,7 +112,7 @@ module.exports = {
             if (tokenBeforeClosingCurly !== openingCurly && !singleLineException && astUtils.isTokenOnSameLine(tokenBeforeClosingCurly, closingCurly)) {
                 context.report({
                     node: closingCurly,
-                    message: CLOSE_MESSAGE_SINGLE,
+                    messageId: "singleLineClose",
                     fix: fixer => fixer.insertTextBefore(closingCurly, "\n")
                 });
             }
@@ -127,7 +129,7 @@ module.exports = {
             if (style === "1tbs" && !astUtils.isTokenOnSameLine(curlyToken, keywordToken)) {
                 context.report({
                     node: curlyToken,
-                    message: CLOSE_MESSAGE,
+                    messageId: "nextLineClose",
                     fix: removeNewlineBetween(curlyToken, keywordToken)
                 });
             }
@@ -135,7 +137,7 @@ module.exports = {
             if (style !== "1tbs" && astUtils.isTokenOnSameLine(curlyToken, keywordToken)) {
                 context.report({
                     node: curlyToken,
-                    message: CLOSE_MESSAGE_STROUSTRUP_ALLMAN,
+                    messageId: "sameLineClose",
                     fix: fixer => fixer.insertTextAfter(curlyToken, "\n")
                 });
             }
diff --git a/lib/rules/callback-return.js b/lib/rules/callback-return.js
index ed85c7181a9..f55fed87db0 100644
--- a/lib/rules/callback-return.js
+++ b/lib/rules/callback-return.js
@@ -20,7 +20,11 @@ module.exports = {
         schema: [{
             type: "array",
             items: { type: "string" }
-        }]
+        }],
+
+        messages: {
+            missingReturn: "Expected return with your callback function."
+        }
     },
 
     create(context) {
@@ -166,7 +170,7 @@ module.exports = {
 
                 // as long as you're the child of a function at this point you should be asked to return
                 if (findClosestParentOfType(node, ["FunctionDeclaration", "FunctionExpression", "ArrowFunctionExpression"])) {
-                    context.report({ node, message: "Expected return with your callback function." });
+                    context.report({ node, messageId: "missingReturn" });
                 }
 
             }
diff --git a/lib/rules/camelcase.js b/lib/rules/camelcase.js
index 86822f97529..84db54ff289 100644
--- a/lib/rules/camelcase.js
+++ b/lib/rules/camelcase.js
@@ -28,7 +28,11 @@ module.exports = {
                 },
                 additionalProperties: false
             }
-        ]
+        ],
+
+        messages: {
+            notCamelCase: "Identifier '{{name}}' is not in camel case."
+        }
     },
 
     create(context) {
@@ -62,7 +66,7 @@ module.exports = {
         function report(node) {
             if (reported.indexOf(node) < 0) {
                 reported.push(node);
-                context.report({ node, message: "Identifier '{{name}}' is not in camel case.", data: { name: node.name } });
+                context.report({ node, messageId: "notCamelCase", data: { name: node.name } });
             }
         }
 
diff --git a/lib/rules/capitalized-comments.js b/lib/rules/capitalized-comments.js
index 19b5f6a7175..c98a4464acb 100644
--- a/lib/rules/capitalized-comments.js
+++ b/lib/rules/capitalized-comments.js
@@ -15,9 +15,7 @@ const astUtils = require("../ast-utils");
 // Helpers
 //------------------------------------------------------------------------------
 
-const ALWAYS_MESSAGE = "Comments should not begin with a lowercase character",
-    NEVER_MESSAGE = "Comments should not begin with an uppercase character",
-    DEFAULT_IGNORE_PATTERN = astUtils.COMMENTS_IGNORE_PATTERN,
+const DEFAULT_IGNORE_PATTERN = astUtils.COMMENTS_IGNORE_PATTERN,
     WHITESPACE = /\s/g,
     MAYBE_URL = /^\s*[^:/?#\s]+:\/\/[^?#]/, // TODO: Combine w/ max-len pattern?
     DEFAULTS = {
@@ -132,7 +130,12 @@ module.exports = {
                     }
                 ]
             }
-        ]
+        ],
+
+        messages: {
+            unexpectedLowercaseComment: "Comments should not begin with a lowercase character",
+            unexpectedUppercaseComment: "Comments should not begin with an uppercase character"
+        }
     },
 
     create(context) {
@@ -267,14 +270,14 @@ module.exports = {
                 commentValid = isCommentValid(comment, options);
 
             if (!commentValid) {
-                const message = capitalize === "always"
-                    ? ALWAYS_MESSAGE
-                    : NEVER_MESSAGE;
+                const messageId = capitalize === "always"
+                    ? "unexpectedLowercaseComment"
+                    : "unexpectedUppercaseComment";
 
                 context.report({
                     node: null, // Intentionally using loc instead
                     loc: comment.loc,
-                    message,
+                    messageId,
                     fix(fixer) {
                         const match = comment.value.match(LETTER_PATTERN);
 
diff --git a/lib/rules/class-methods-use-this.js b/lib/rules/class-methods-use-this.js
index 774086780ae..b7d94135bb7 100644
--- a/lib/rules/class-methods-use-this.js
+++ b/lib/rules/class-methods-use-this.js
@@ -28,7 +28,11 @@ module.exports = {
                 }
             },
             additionalProperties: false
-        }]
+        }],
+
+        messages: {
+            missingThis: "Expected 'this' to be used by class method '{{name}}'."
+        }
     },
     create(context) {
         const config = context.options[0] ? Object.assign({}, context.options[0]) : {};
@@ -80,9 +84,9 @@ module.exports = {
             if (isIncludedInstanceMethod(node.parent) && !methodUsesThis) {
                 context.report({
                     node,
-                    message: "Expected 'this' to be used by class method '{{classMethod}}'.",
+                    messageId: "missingThis",
                     data: {
-                        classMethod: node.parent.key.name
+                        name: node.parent.key.name
                     }
                 });
             }
diff --git a/lib/rules/comma-dangle.js b/lib/rules/comma-dangle.js
index 180979d4032..50de7b59b22 100644
--- a/lib/rules/comma-dangle.js
+++ b/lib/rules/comma-dangle.js
@@ -124,14 +124,17 @@ module.exports = {
                     ]
                 }
             ]
+        },
+
+        messages: {
+            unexpected: "Unexpected trailing comma.",
+            missing: "Missing trailing comma."
         }
     },
 
     create(context) {
         const options = normalizeOptions(context.options[0]);
         const sourceCode = context.getSourceCode();
-        const UNEXPECTED_MESSAGE = "Unexpected trailing comma.";
-        const MISSING_MESSAGE = "Missing trailing comma.";
 
         /**
          * Gets the last item of the given node.
@@ -230,7 +233,7 @@ module.exports = {
                 context.report({
                     node: lastItem,
                     loc: trailingToken.loc.start,
-                    message: UNEXPECTED_MESSAGE,
+                    messageId: "unexpected",
                     fix(fixer) {
                         return fixer.remove(trailingToken);
                     }
@@ -267,7 +270,7 @@ module.exports = {
                 context.report({
                     node: lastItem,
                     loc: trailingToken.loc.end,
-                    message: MISSING_MESSAGE,
+                    messageId: "missing",
                     fix(fixer) {
                         return fixer.insertTextAfter(trailingToken, ",");
                     }
diff --git a/lib/rules/comma-spacing.js b/lib/rules/comma-spacing.js
index dd3de7f3543..2a48e54d51c 100644
--- a/lib/rules/comma-spacing.js
+++ b/lib/rules/comma-spacing.js
@@ -34,7 +34,12 @@ module.exports = {
                 },
                 additionalProperties: false
             }
-        ]
+        ],
+
+        messages: {
+            missing: "A space is required {{loc}} ','.",
+            unexpected: "There should be no space {{loc}} ','."
+        }
     },
 
     create(context) {
@@ -57,17 +62,17 @@ module.exports = {
         /**
          * Reports a spacing error with an appropriate message.
          * @param {ASTNode} node The binary expression node to report.
-         * @param {string} dir Is the error "before" or "after" the comma?
+         * @param {string} loc Is the error "before" or "after" the comma?
          * @param {ASTNode} otherNode The node at the left or right of `node`
          * @returns {void}
          * @private
          */
-        function report(node, dir, otherNode) {
+        function report(node, loc, otherNode) {
             context.report({
                 node,
                 fix(fixer) {
-                    if (options[dir]) {
-                        if (dir === "before") {
+                    if (options[loc]) {
+                        if (loc === "before") {
                             return fixer.insertTextBefore(node, " ");
                         }
                         return fixer.insertTextAfter(node, " ");
@@ -76,7 +81,7 @@ module.exports = {
                     let start, end;
                     const newText = "";
 
-                    if (dir === "before") {
+                    if (loc === "before") {
                         start = otherNode.range[1];
                         end = node.range[0];
                     } else {
@@ -87,11 +92,9 @@ module.exports = {
                     return fixer.replaceTextRange([start, end], newText);
 
                 },
-                message: options[dir]
-                    ? "A space is required {{dir}} ','."
-                    : "There should be no space {{dir}} ','.",
+                messageId: options[loc] ? "missing" : "unexpected",
                 data: {
-                    dir
+                    loc
                 }
             });
         }
diff --git a/lib/rules/comma-style.js b/lib/rules/comma-style.js
index 1d7eef231b5..5ba2dbb28b2 100644
--- a/lib/rules/comma-style.js
+++ b/lib/rules/comma-style.js
@@ -36,7 +36,12 @@ module.exports = {
                 },
                 additionalProperties: false
             }
-        ]
+        ],
+        messages: {
+            unexpectedLineBeforeAndAfterComma: "Bad line breaking before and after ','.",
+            expectedCommaFirst: "',' should be placed first.",
+            expectedCommaLast: "',' should be placed last."
+        }
     },
 
     create(context) {
@@ -135,7 +140,7 @@ module.exports = {
                         line: commaToken.loc.end.line,
                         column: commaToken.loc.start.column
                     },
-                    message: "Bad line breaking before and after ','.",
+                    messageId: "unexpectedLineBeforeAndAfterComma",
                     fix: getFixerFunction("between", previousItemToken, commaToken, currentItemToken)
                 });
 
@@ -143,7 +148,7 @@ module.exports = {
 
                 context.report({
                     node: reportItem,
-                    message: "',' should be placed first.",
+                    messageId: "expectedCommaFirst",
                     fix: getFixerFunction(style, previousItemToken, commaToken, currentItemToken)
                 });
 
@@ -155,7 +160,7 @@ module.exports = {
                         line: commaToken.loc.end.line,
                         column: commaToken.loc.end.column
                     },
-                    message: "',' should be placed last.",
+                    messageId: "expectedCommaLast",
                     fix: getFixerFunction(style, previousItemToken, commaToken, currentItemToken)
                 });
             }
diff --git a/lib/rules/complexity.js b/lib/rules/complexity.js
index 1838d4bf8ed..0b864413659 100644
--- a/lib/rules/complexity.js
+++ b/lib/rules/complexity.js
@@ -50,7 +50,11 @@ module.exports = {
                     }
                 ]
             }
-        ]
+        ],
+
+        messages: {
+            complex: "{{name}} has a complexity of {{complexity}}."
+        }
     },
 
     create(context) {
@@ -96,7 +100,7 @@ module.exports = {
             if (complexity > THRESHOLD) {
                 context.report({
                     node,
-                    message: "{{name}} has a complexity of {{complexity}}.",
+                    messageId: "complex",
                     data: { name, complexity }
                 });
             }
diff --git a/lib/rules/computed-property-spacing.js b/lib/rules/computed-property-spacing.js
index 57408afb453..51334a2ab4d 100644
--- a/lib/rules/computed-property-spacing.js
+++ b/lib/rules/computed-property-spacing.js
@@ -25,7 +25,15 @@ module.exports = {
             {
                 enum: ["always", "never"]
             }
-        ]
+        ],
+
+        messages: {
+            unexpectedSpaceBefore: "There should be no space before '{{tokenValue}}'.",
+            unexpectedSpaceAfter: "There should be no space after '{{tokenValue}}'.",
+
+            missingSpaceBefore: "A space is required before '{{tokenValue}}'.",
+            missingSpaceAfter: "A space is required after '{{tokenValue}}'."
+        }
     },
 
     create(context) {
@@ -47,7 +55,7 @@ module.exports = {
             context.report({
                 node,
                 loc: token.loc.start,
-                message: "There should be no space after '{{tokenValue}}'.",
+                messageId: "unexpectedSpaceAfter",
                 data: {
                     tokenValue: token.value
                 },
@@ -68,7 +76,7 @@ module.exports = {
             context.report({
                 node,
                 loc: token.loc.start,
-                message: "There should be no space before '{{tokenValue}}'.",
+                messageId: "unexpectedSpaceBefore",
                 data: {
                     tokenValue: token.value
                 },
@@ -88,7 +96,7 @@ module.exports = {
             context.report({
                 node,
                 loc: token.loc.start,
-                message: "A space is required after '{{tokenValue}}'.",
+                messageId: "missingSpaceAfter",
                 data: {
                     tokenValue: token.value
                 },
@@ -108,7 +116,7 @@ module.exports = {
             context.report({
                 node,
                 loc: token.loc.start,
-                message: "A space is required before '{{tokenValue}}'.",
+                messageId: "missingSpaceBefore",
                 data: {
                     tokenValue: token.value
                 },
diff --git a/lib/rules/consistent-return.js b/lib/rules/consistent-return.js
index a436dd1fc0c..c86b1717ef0 100644
--- a/lib/rules/consistent-return.js
+++ b/lib/rules/consistent-return.js
@@ -68,7 +68,13 @@ module.exports = {
                 }
             },
             additionalProperties: false
-        }]
+        }],
+
+        messages: {
+            missingReturn: "Expected to return a value at the end of {{name}}.",
+            missingReturnValue: "{{name}} expected a return value.",
+            unexpectedReturnValue: "{{name}} expected no return value."
+        }
     },
 
     create(context) {
@@ -129,7 +135,7 @@ module.exports = {
             context.report({
                 node,
                 loc,
-                message: "Expected to return a value at the end of {{name}}.",
+                messageId: "missingReturn",
                 data: { name }
             });
         }
@@ -143,7 +149,7 @@ module.exports = {
                     codePath,
                     hasReturn: false,
                     hasReturnValue: false,
-                    message: "",
+                    messageId: "",
                     node
                 };
             },
@@ -163,17 +169,16 @@ module.exports = {
                 if (!funcInfo.hasReturn) {
                     funcInfo.hasReturn = true;
                     funcInfo.hasReturnValue = hasReturnValue;
-                    funcInfo.message = "{{name}} expected {{which}} return value.";
+                    funcInfo.messageId = hasReturnValue ? "missingReturnValue" : "unexpectedReturnValue";
                     funcInfo.data = {
                         name: funcInfo.node.type === "Program"
                             ? "Program"
-                            : lodash.upperFirst(astUtils.getFunctionNameWithKind(funcInfo.node)),
-                        which: hasReturnValue ? "a" : "no"
+                            : lodash.upperFirst(astUtils.getFunctionNameWithKind(funcInfo.node))
                     };
                 } else if (funcInfo.hasReturnValue !== hasReturnValue) {
                     context.report({
                         node,
-                        message: funcInfo.message,
+                        messageId: funcInfo.messageId,
                         data: funcInfo.data
                     });
                 }
diff --git a/lib/rules/consistent-this.js b/lib/rules/consistent-this.js
index 60690007f2d..5cc3a647dab 100644
--- a/lib/rules/consistent-this.js
+++ b/lib/rules/consistent-this.js
@@ -24,6 +24,11 @@ module.exports = {
                 minLength: 1
             },
             uniqueItems: true
+        },
+
+        messages: {
+            aliasNotAssignedToThis: "Designated alias '{{name}}' is not assigned to 'this'.",
+            unexpectedAlias: "Unexpected alias '{{name}}' for 'this'."
         }
     },
 
@@ -40,11 +45,11 @@ module.exports = {
          * Reports that a variable declarator or assignment expression is assigning
          * a non-'this' value to the specified alias.
          * @param {ASTNode} node - The assigning node.
-         * @param {string} alias - the name of the alias that was incorrectly used.
+         * @param {string}  name - the name of the alias that was incorrectly used.
          * @returns {void}
          */
-        function reportBadAssignment(node, alias) {
-            context.report({ node, message: "Designated alias '{{alias}}' is not assigned to 'this'.", data: { alias } });
+        function reportBadAssignment(node, name) {
+            context.report({ node, messageId: "aliasNotAssignedToThis", data: { name } });
         }
 
         /**
@@ -63,7 +68,7 @@ module.exports = {
                     reportBadAssignment(node, name);
                 }
             } else if (isThis) {
-                context.report({ node, message: "Unexpected alias '{{name}}' for 'this'.", data: { name } });
+                context.report({ node, messageId: "unexpectedAlias", data: { name } });
             }
         }
 
diff --git a/lib/rules/constructor-super.js b/lib/rules/constructor-super.js
index 30637472f19..3cbc2f59f89 100644
--- a/lib/rules/constructor-super.js
+++ b/lib/rules/constructor-super.js
@@ -99,7 +99,16 @@ module.exports = {
             url: "https://eslint.org/docs/rules/constructor-super"
         },
 
-        schema: []
+        schema: [],
+
+        messages: {
+            missingSome: "Lacked a call of 'super()' in some code paths.",
+            missingAll: "Expected to call 'super()'.",
+
+            duplicate: "Unexpected duplicate 'super()'.",
+            badSuper: "Unexpected 'super()' because 'super' is not a constructor.",
+            unexpected: "Unexpected 'super()'."
+        }
     },
 
     create(context) {
@@ -210,9 +219,9 @@ module.exports = {
 
                 if (!calledInEveryPaths) {
                     context.report({
-                        message: calledInSomePaths
-                            ? "Lacked a call of 'super()' in some code paths."
-                            : "Expected to call 'super()'.",
+                        messageId: calledInSomePaths
+                            ? "missingSome"
+                            : "missingAll",
                         node: node.parent
                     });
                 }
@@ -281,7 +290,7 @@ module.exports = {
                                 const node = nodes[i];
 
                                 context.report({
-                                    message: "Unexpected duplicate 'super()'.",
+                                    messageId: "duplicate",
                                     node
                                 });
                             }
@@ -325,12 +334,12 @@ module.exports = {
                     if (info) {
                         if (duplicate) {
                             context.report({
-                                message: "Unexpected duplicate 'super()'.",
+                                messageId: "duplicate",
                                 node
                             });
                         } else if (!funcInfo.superIsConstructor) {
                             context.report({
-                                message: "Unexpected 'super()' because 'super' is not a constructor.",
+                                messageId: "badSuper",
                                 node
                             });
                         } else {
@@ -339,7 +348,7 @@ module.exports = {
                     }
                 } else if (funcInfo.codePath.currentSegments.some(isReachable)) {
                     context.report({
-                        message: "Unexpected 'super()'.",
+                        messageId: "unexpected",
                         node
                     });
                 }
diff --git a/lib/rules/curly.js b/lib/rules/curly.js
index 7fdf57eda17..f1e4f49c63a 100644
--- a/lib/rules/curly.js
+++ b/lib/rules/curly.js
@@ -51,7 +51,14 @@ module.exports = {
             ]
         },
 
-        fixable: "code"
+        fixable: "code",
+
+        messages: {
+            missingCurlyAfter: "Expected { after '{{name}}'.",
+            missingCurlyAfterCondition: "Expected { after '{{name}}' condition.",
+            unexpectedCurlyAfter: "Unnecessary { after '{{name}}'.",
+            unexpectedCurlyAfterCondition: "Unnecessary { after '{{name}}' condition."
+        }
     },
 
     create(context) {
@@ -142,28 +149,6 @@ module.exports = {
             return false;
         }
 
-        /**
-         * Reports "Expected { after ..." error
-         * @param {ASTNode} node The node to report.
-         * @param {ASTNode} bodyNode The body node that is incorrectly missing curly brackets
-         * @param {string} name The name to report.
-         * @param {string} suffix Additional string to add to the end of a report.
-         * @returns {void}
-         * @private
-         */
-        function reportExpectedBraceError(node, bodyNode, name, suffix) {
-            context.report({
-                node,
-                loc: (name !== "else" ? node : getElseKeyword(node)).loc.start,
-                message: "Expected { after '{{name}}'{{suffix}}.",
-                data: {
-                    name,
-                    suffix: (suffix ? ` ${suffix}` : "")
-                },
-                fix: fixer => fixer.replaceText(bodyNode, `{${sourceCode.getText(bodyNode)}}`)
-            });
-        }
-
         /**
          * Determines if a semicolon needs to be inserted after removing a set of curly brackets, in order to avoid a SyntaxError.
          * @param {Token} closingBracket The } token
@@ -218,62 +203,12 @@ module.exports = {
             return false;
         }
 
-        /**
-         * Reports "Unnecessary { after ..." error
-         * @param {ASTNode} node The node to report.
-         * @param {ASTNode} bodyNode The block statement that is incorrectly surrounded by parens
-         * @param {string} name The name to report.
-         * @param {string} suffix Additional string to add to the end of a report.
-         * @returns {void}
-         * @private
-         */
-        function reportUnnecessaryBraceError(node, bodyNode, name, suffix) {
-            context.report({
-                node,
-                loc: (name !== "else" ? node : getElseKeyword(node)).loc.start,
-                message: "Unnecessary { after '{{name}}'{{suffix}}.",
-                data: {
-                    name,
-                    suffix: (suffix ? ` ${suffix}` : "")
-                },
-                fix(fixer) {
-
-                    /*
-                     * `do while` expressions sometimes need a space to be inserted after `do`.
-                     * e.g. `do{foo()} while (bar)` should be corrected to `do foo() while (bar)`
-                     */
-                    const needsPrecedingSpace = node.type === "DoWhileStatement" &&
-                        sourceCode.getTokenBefore(bodyNode).range[1] === bodyNode.range[0] &&
-                        !astUtils.canTokensBeAdjacent("do", sourceCode.getFirstToken(bodyNode, { skip: 1 }));
-
-                    const openingBracket = sourceCode.getFirstToken(bodyNode);
-                    const closingBracket = sourceCode.getLastToken(bodyNode);
-                    const lastTokenInBlock = sourceCode.getTokenBefore(closingBracket);
-
-                    if (needsSemicolon(closingBracket)) {
-
-                        /*
-                         * If removing braces would cause a SyntaxError due to multiple statements on the same line (or
-                         * change the semantics of the code due to ASI), don't perform a fix.
-                         */
-                        return null;
-                    }
-
-                    const resultingBodyText = sourceCode.getText().slice(openingBracket.range[1], lastTokenInBlock.range[0]) +
-                        sourceCode.getText(lastTokenInBlock) +
-                        sourceCode.getText().slice(lastTokenInBlock.range[1], closingBracket.range[0]);
-
-                    return fixer.replaceText(bodyNode, (needsPrecedingSpace ? " " : "") + resultingBodyText);
-                }
-            });
-        }
-
         /**
          * Prepares to check the body of a node to see if it's a block statement.
          * @param {ASTNode} node The node to report if there's a problem.
          * @param {ASTNode} body The body node to check for blocks.
          * @param {string} name The name to report if there's a problem.
-         * @param {string} suffix Additional string to add to the end of a report.
+         * @param {{ condition: boolean }} opts Options to pass to the report functions
          * @returns {Object} a prepared check object, with "actual", "expected", "check" properties.
          *   "actual" will be `true` or `false` whether the body is already a block statement.
          *   "expected" will be `true` or `false` if the body should be a block statement or not, or
@@ -282,7 +217,7 @@ module.exports = {
          *   "check" will be a function reporting appropriate problems depending on the other
          *   properties.
          */
-        function prepareCheck(node, body, name, suffix) {
+        function prepareCheck(node, body, name, opts) {
             const hasBlock = (body.type === "BlockStatement");
             let expected = null;
 
@@ -314,9 +249,53 @@ module.exports = {
                 check() {
                     if (this.expected !== null && this.expected !== this.actual) {
                         if (this.expected) {
-                            reportExpectedBraceError(node, body, name, suffix);
+                            context.report({
+                                node,
+                                loc: (name !== "else" ? node : getElseKeyword(node)).loc.start,
+                                messageId: opts && opts.condition ? "missingCurlyAfterCondition" : "missingCurlyAfter",
+                                data: {
+                                    name
+                                },
+                                fix: fixer => fixer.replaceText(body, `{${sourceCode.getText(body)}}`)
+                            });
                         } else {
-                            reportUnnecessaryBraceError(node, body, name, suffix);
+                            context.report({
+                                node,
+                                loc: (name !== "else" ? node : getElseKeyword(node)).loc.start,
+                                messageId: opts && opts.condition ? "unexpectedCurlyAfterCondition" : "unexpectedCurlyAfter",
+                                data: {
+                                    name
+                                },
+                                fix(fixer) {
+
+                                    /*
+                                     * `do while` expressions sometimes need a space to be inserted after `do`.
+                                     * e.g. `do{foo()} while (bar)` should be corrected to `do foo() while (bar)`
+                                     */
+                                    const needsPrecedingSpace = node.type === "DoWhileStatement" &&
+                                        sourceCode.getTokenBefore(body).range[1] === body.range[0] &&
+                                        !astUtils.canTokensBeAdjacent("do", sourceCode.getFirstToken(body, { skip: 1 }));
+
+                                    const openingBracket = sourceCode.getFirstToken(body);
+                                    const closingBracket = sourceCode.getLastToken(body);
+                                    const lastTokenInBlock = sourceCode.getTokenBefore(closingBracket);
+
+                                    if (needsSemicolon(closingBracket)) {
+
+                                        /*
+                                         * If removing braces would cause a SyntaxError due to multiple statements on the same line (or
+                                         * change the semantics of the code due to ASI), don't perform a fix.
+                                         */
+                                        return null;
+                                    }
+
+                                    const resultingBodyText = sourceCode.getText().slice(openingBracket.range[1], lastTokenInBlock.range[0]) +
+                                        sourceCode.getText(lastTokenInBlock) +
+                                        sourceCode.getText().slice(lastTokenInBlock.range[1], closingBracket.range[0]);
+
+                                    return fixer.replaceText(body, (needsPrecedingSpace ? " " : "") + resultingBodyText);
+                                }
+                            });
                         }
                     }
                 }
@@ -333,7 +312,7 @@ module.exports = {
             const preparedChecks = [];
 
             do {
-                preparedChecks.push(prepareCheck(node, node.consequent, "if", "condition"));
+                preparedChecks.push(prepareCheck(node, node.consequent, "if", { condition: true }));
                 if (node.alternate && node.alternate.type !== "IfStatement") {
                     preparedChecks.push(prepareCheck(node, node.alternate, "else"));
                     break;
@@ -377,7 +356,7 @@ module.exports = {
             },
 
             WhileStatement(node) {
-                prepareCheck(node, node.body, "while", "condition").check();
+                prepareCheck(node, node.body, "while", { condition: true }).check();
             },
 
             DoWhileStatement(node) {
@@ -385,7 +364,7 @@ module.exports = {
             },
 
             ForStatement(node) {
-                prepareCheck(node, node.body, "for", "condition").check();
+                prepareCheck(node, node.body, "for", { condition: true }).check();
             },
 
             ForInStatement(node) {
diff --git a/lib/rules/default-case.js b/lib/rules/default-case.js
index a66300a99b5..cf123198f4a 100644
--- a/lib/rules/default-case.js
+++ b/lib/rules/default-case.js
@@ -27,7 +27,11 @@ module.exports = {
                 }
             },
             additionalProperties: false
-        }]
+        }],
+
+        messages: {
+            missingDefaultCase: "Expected a default case."
+        }
     },
 
     create(context) {
@@ -82,7 +86,7 @@ module.exports = {
                     }
 
                     if (!comment || !commentPattern.test(comment.value.trim())) {
-                        context.report({ node, message: "Expected a default case." });
+                        context.report({ node, messageId: "missingDefaultCase" });
                     }
                 }
             }
diff --git a/lib/rules/dot-location.js b/lib/rules/dot-location.js
index c02476e0354..7ff8ca65ae4 100644
--- a/lib/rules/dot-location.js
+++ b/lib/rules/dot-location.js
@@ -26,7 +26,12 @@ module.exports = {
             }
         ],
 
-        fixable: "code"
+        fixable: "code",
+
+        messages: {
+            expectedDotAfterObject: "Expected dot to be on same line as object.",
+            expectedDotBeforeProperty: "Expected dot to be on same line as property."
+        }
     },
 
     create(context) {
@@ -58,7 +63,7 @@ module.exports = {
                         context.report({
                             node,
                             loc: dot.loc.start,
-                            message: "Expected dot to be on same line as object.",
+                            messageId: "expectedDotAfterObject",
                             fix: fixer => fixer.replaceTextRange([obj.range[1], prop.range[0]], `${neededTextAfterObj}.${textBeforeDot}${textAfterDot}`)
                         });
                     }
@@ -66,7 +71,7 @@ module.exports = {
                     context.report({
                         node,
                         loc: dot.loc.start,
-                        message: "Expected dot to be on same line as property.",
+                        messageId: "expectedDotBeforeProperty",
                         fix: fixer => fixer.replaceTextRange([obj.range[1], prop.range[0]], `${textBeforeDot}${textAfterDot}.`)
                     });
                 }
diff --git a/lib/rules/dot-notation.js b/lib/rules/dot-notation.js
index 10c73b41f04..c381661d41f 100644
--- a/lib/rules/dot-notation.js
+++ b/lib/rules/dot-notation.js
@@ -41,7 +41,12 @@ module.exports = {
             }
         ],
 
-        fixable: "code"
+        fixable: "code",
+
+        messages: {
+            useDot: "[{{key}}] is better written in dot notation.",
+            useBrackets: ".{{key}} is a syntax error."
+        }
     },
 
     create(context) {
@@ -71,9 +76,9 @@ module.exports = {
 
                 context.report({
                     node: node.property,
-                    message: "[{{propertyValue}}] is better written in dot notation.",
+                    messageId: "useDot",
                     data: {
-                        propertyValue: formattedValue
+                        key: formattedValue
                     },
                     fix(fixer) {
                         const leftBracket = sourceCode.getTokenAfter(node.object, astUtils.isOpeningBracketToken);
@@ -124,9 +129,9 @@ module.exports = {
                 ) {
                     context.report({
                         node: node.property,
-                        message: ".{{propertyName}} is a syntax error.",
+                        messageId: "useBrackets",
                         data: {
-                            propertyName: node.property.name
+                            key: node.property.name
                         },
                         fix(fixer) {
                             const dot = sourceCode.getTokenBefore(node.property);
diff --git a/lib/rules/eol-last.js b/lib/rules/eol-last.js
index f96352676c7..3ecf4227399 100644
--- a/lib/rules/eol-last.js
+++ b/lib/rules/eol-last.js
@@ -27,7 +27,11 @@ module.exports = {
             {
                 enum: ["always", "never", "unix", "windows"]
             }
-        ]
+        ],
+        messages: {
+            missing: "Newline required at end of file but not found.",
+            unexpected: "Newline not allowed at end of file."
+        }
     },
     create(context) {
 
@@ -75,7 +79,7 @@ module.exports = {
                     context.report({
                         node,
                         loc: location,
-                        message: "Newline required at end of file but not found.",
+                        messageId: "missing",
                         fix(fixer) {
                             return fixer.insertTextAfterRange([0, src.length], appendCRLF ? CRLF : LF);
                         }
@@ -86,7 +90,7 @@ module.exports = {
                     context.report({
                         node,
                         loc: location,
-                        message: "Newline not allowed at end of file.",
+                        messageId: "unexpected",
                         fix(fixer) {
                             const finalEOLs = /(?:\r?\n)+$/,
                                 match = finalEOLs.exec(sourceCode.text),
diff --git a/lib/rules/eqeqeq.js b/lib/rules/eqeqeq.js
index fc65450af4b..ec9d0a78218 100644
--- a/lib/rules/eqeqeq.js
+++ b/lib/rules/eqeqeq.js
@@ -56,7 +56,11 @@ module.exports = {
             ]
         },
 
-        fixable: "code"
+        fixable: "code",
+
+        messages: {
+            unexpected: "Expected '{{expectedOperator}}' and instead saw '{{actualOperator}}'."
+        }
     },
 
     create(context) {
@@ -134,7 +138,7 @@ module.exports = {
             context.report({
                 node,
                 loc: getOperatorLocation(node),
-                message: "Expected '{{expectedOperator}}' and instead saw '{{actualOperator}}'.",
+                messageId: "unexpected",
                 data: { expectedOperator, actualOperator: node.operator },
                 fix(fixer) {
 
diff --git a/lib/rules/no-alert.js b/lib/rules/no-alert.js
index b4fd2312150..69d419da1c5 100644
--- a/lib/rules/no-alert.js
+++ b/lib/rules/no-alert.js
@@ -23,17 +23,6 @@ function isProhibitedIdentifier(name) {
     return /^(alert|confirm|prompt)$/.test(name);
 }
 
-/**
- * Reports the given node and identifier name.
- * @param {RuleContext} context The ESLint rule context.
- * @param {ASTNode} node The node to report on.
- * @param {string} identifierName The name of the identifier.
- * @returns {void}
- */
-function report(context, node, identifierName) {
-    context.report(node, "Unexpected {{name}}.", { name: identifierName });
-}
-
 /**
  * Finds the eslint-scope reference in the given scope.
  * @param {Object} scope The scope to search.
@@ -92,7 +81,11 @@ module.exports = {
             url: "https://eslint.org/docs/rules/no-alert"
         },
 
-        schema: []
+        schema: [],
+
+        messages: {
+            unexpected: "Unexpected {{name}}."
+        }
     },
 
     create(context) {
@@ -103,17 +96,25 @@ module.exports = {
 
                 // without window.
                 if (callee.type === "Identifier") {
-                    const identifierName = callee.name;
+                    const name = callee.name;
 
                     if (!isShadowed(currentScope, callee) && isProhibitedIdentifier(callee.name)) {
-                        report(context, node, identifierName);
+                        context.report({
+                            node,
+                            messageId: "unexpected",
+                            data: { name }
+                        });
                     }
 
                 } else if (callee.type === "MemberExpression" && isGlobalThisReferenceOrGlobalWindow(currentScope, callee.object)) {
-                    const identifierName = getPropertyName(callee);
-
-                    if (isProhibitedIdentifier(identifierName)) {
-                        report(context, node, identifierName);
+                    const name = getPropertyName(callee);
+
+                    if (isProhibitedIdentifier(name)) {
+                        context.report({
+                            node,
+                            messageId: "unexpected",
+                            data: { name }
+                        });
                     }
                 }
 
diff --git a/lib/rules/no-array-constructor.js b/lib/rules/no-array-constructor.js
index 187389fdff3..51676f78211 100644
--- a/lib/rules/no-array-constructor.js
+++ b/lib/rules/no-array-constructor.js
@@ -18,7 +18,11 @@ module.exports = {
             url: "https://eslint.org/docs/rules/no-array-constructor"
         },
 
-        schema: []
+        schema: [],
+
+        messages: {
+            preferLiteral: "The array literal notation [] is preferable."
+        }
     },
 
     create(context) {
@@ -35,7 +39,7 @@ module.exports = {
                 node.callee.type === "Identifier" &&
                 node.callee.name === "Array"
             ) {
-                context.report({ node, message: "The array literal notation [] is preferrable." });
+                context.report({ node, messageId: "preferLiteral" });
             }
         }
 
diff --git a/lib/rules/no-await-in-loop.js b/lib/rules/no-await-in-loop.js
index 7d4f8a0a6ba..7a9427e6abf 100644
--- a/lib/rules/no-await-in-loop.js
+++ b/lib/rules/no-await-in-loop.js
@@ -31,7 +31,10 @@ module.exports = {
             recommended: false,
             url: "https://eslint.org/docs/rules/no-await-in-loop"
         },
-        schema: []
+        schema: [],
+        messages: {
+            unexpectedAwait: "Unexpected `await` inside a loop."
+        }
     },
     create(context) {
         return {
@@ -72,7 +75,7 @@ module.exports = {
                         ) {
                             context.report({
                                 node,
-                                message: "Unexpected `await` inside a loop."
+                                messageId: "unexpectedAwait"
                             });
                             return;
                         }
diff --git a/lib/rules/no-bitwise.js b/lib/rules/no-bitwise.js
index 8376674f65f..36bbdaf349c 100644
--- a/lib/rules/no-bitwise.js
+++ b/lib/rules/no-bitwise.js
@@ -46,7 +46,11 @@ module.exports = {
                 },
                 additionalProperties: false
             }
-        ]
+        ],
+
+        messages: {
+            unexpected: "Unexpected use of '{{operator}}'."
+        }
     },
 
     create(context) {
@@ -60,7 +64,7 @@ module.exports = {
          * @returns {void}
          */
         function report(node) {
-            context.report({ node, message: "Unexpected use of '{{operator}}'.", data: { operator: node.operator } });
+            context.report({ node, messageId: "unexpected", data: { operator: node.operator } });
         }
 
         /**
diff --git a/lib/rules/no-buffer-constructor.js b/lib/rules/no-buffer-constructor.js
index 55f181ee697..2cf2ee47c86 100644
--- a/lib/rules/no-buffer-constructor.js
+++ b/lib/rules/no-buffer-constructor.js
@@ -16,7 +16,10 @@ module.exports = {
             recommended: false,
             url: "https://eslint.org/docs/rules/no-buffer-constructor"
         },
-        schema: []
+        schema: [],
+        messages: {
+            deprecated: "{{expr}} is deprecated. Use Buffer.from(), Buffer.alloc(), or Buffer.allocUnsafe() instead."
+        }
     },
 
     create(context) {
@@ -29,8 +32,8 @@ module.exports = {
             "CallExpression[callee.name='Buffer'], NewExpression[callee.name='Buffer']"(node) {
                 context.report({
                     node,
-                    message: "{{example}} is deprecated. Use Buffer.from(), Buffer.alloc(), or Buffer.allocUnsafe() instead.",
-                    data: { example: node.type === "CallExpression" ? "Buffer()" : "new Buffer()" }
+                    messageId: "deprecated",
+                    data: { expr: node.type === "CallExpression" ? "Buffer()" : "new Buffer()" }
                 });
             }
         };
diff --git a/lib/rules/no-caller.js b/lib/rules/no-caller.js
index df10bf3736b..9756b212ffe 100644
--- a/lib/rules/no-caller.js
+++ b/lib/rules/no-caller.js
@@ -18,7 +18,11 @@ module.exports = {
             url: "https://eslint.org/docs/rules/no-caller"
         },
 
-        schema: []
+        schema: [],
+
+        messages: {
+            unexpected: "Avoid arguments.{{prop}}."
+        }
     },
 
     create(context) {
@@ -30,7 +34,7 @@ module.exports = {
                     propertyName = node.property.name;
 
                 if (objectName === "arguments" && !node.computed && propertyName && propertyName.match(/^calle[er]$/)) {
-                    context.report({ node, message: "Avoid arguments.{{property}}.", data: { property: propertyName } });
+                    context.report({ node, messageId: "unexpected", data: { prop: propertyName } });
                 }
 
             }
diff --git a/lib/rules/no-case-declarations.js b/lib/rules/no-case-declarations.js
index 03c730ddbdb..862be4c57d9 100644
--- a/lib/rules/no-case-declarations.js
+++ b/lib/rules/no-case-declarations.js
@@ -17,7 +17,11 @@ module.exports = {
             url: "https://eslint.org/docs/rules/no-case-declarations"
         },
 
-        schema: []
+        schema: [],
+
+        messages: {
+            unexpected: "Unexpected lexical declaration in case block."
+        }
     },
 
     create(context) {
@@ -47,7 +51,7 @@ module.exports = {
                     if (isLexicalDeclaration(statement)) {
                         context.report({
                             node,
-                            message: "Unexpected lexical declaration in case block."
+                            messageId: "unexpected"
                         });
                     }
                 }
diff --git a/lib/rules/no-catch-shadow.js b/lib/rules/no-catch-shadow.js
index 69a4e6aff85..907792278fc 100644
--- a/lib/rules/no-catch-shadow.js
+++ b/lib/rules/no-catch-shadow.js
@@ -24,7 +24,11 @@ module.exports = {
             url: "https://eslint.org/docs/rules/no-catch-shadow"
         },
 
-        schema: []
+        schema: [],
+
+        messages: {
+            mutable: "Value of '{{name}}' may be overwritten in IE 8 and earlier."
+        }
     },
 
     create(context) {
@@ -61,7 +65,7 @@ module.exports = {
                 }
 
                 if (paramIsShadowing(scope, node.param.name)) {
-                    context.report({ node, message: "Value of '{{name}}' may be overwritten in IE 8 and earlier.", data: { name: node.param.name } });
+                    context.report({ node, messageId: "mutable", data: { name: node.param.name } });
                 }
             }
         };
diff --git a/lib/rules/no-class-assign.js b/lib/rules/no-class-assign.js
index 56e75122a25..58dddd6a684 100644
--- a/lib/rules/no-class-assign.js
+++ b/lib/rules/no-class-assign.js
@@ -20,7 +20,11 @@ module.exports = {
             url: "https://eslint.org/docs/rules/no-class-assign"
         },
 
-        schema: []
+        schema: [],
+
+        messages: {
+            class: "'{{name}}' is a class."
+        }
     },
 
     create(context) {
@@ -32,7 +36,7 @@ module.exports = {
          */
         function checkVariable(variable) {
             astUtils.getModifyingReferences(variable.references).forEach(reference => {
-                context.report({ node: reference.identifier, message: "'{{name}}' is a class.", data: { name: reference.identifier.name } });
+                context.report({ node: reference.identifier, messageId: "class", data: { name: reference.identifier.name } });
 
             });
         }
diff --git a/lib/rules/no-compare-neg-zero.js b/lib/rules/no-compare-neg-zero.js
index 09cf2950630..6903bd06544 100644
--- a/lib/rules/no-compare-neg-zero.js
+++ b/lib/rules/no-compare-neg-zero.js
@@ -17,7 +17,10 @@ module.exports = {
             url: "https://eslint.org/docs/rules/no-compare-neg-zero"
         },
         fixable: null,
-        schema: []
+        schema: [],
+        messages: {
+            unexpected: "Do not use the '{{operator}}' operator to compare against -0."
+        }
     },
 
     create(context) {
@@ -43,7 +46,7 @@ module.exports = {
                     if (isNegZero(node.left) || isNegZero(node.right)) {
                         context.report({
                             node,
-                            message: "Do not use the '{{operator}}' operator to compare against -0.",
+                            messageId: "unexpected",
                             data: { operator: node.operator }
                         });
                     }
diff --git a/lib/rules/no-cond-assign.js b/lib/rules/no-cond-assign.js
index e761be14ecd..f949bcc884b 100644
--- a/lib/rules/no-cond-assign.js
+++ b/lib/rules/no-cond-assign.js
@@ -30,7 +30,14 @@ module.exports = {
             {
                 enum: ["except-parens", "always"]
             }
-        ]
+        ],
+
+        messages: {
+            unexpected: "Unexpected assignment within {{type}}.",
+
+            // must match JSHint's error message
+            missing: "Expected a conditional expression and instead saw an assignment."
+        }
     },
 
     create(context) {
@@ -95,11 +102,10 @@ module.exports = {
                 )
             ) {
 
-                // must match JSHint's error message
                 context.report({
                     node,
                     loc: node.test.loc.start,
-                    message: "Expected a conditional expression and instead saw an assignment."
+                    messageId: "missing"
                 });
             }
         }
@@ -115,7 +121,7 @@ module.exports = {
             if (ancestor) {
                 context.report({
                     node: ancestor,
-                    message: "Unexpected assignment within {{type}}.",
+                    messageId: "unexpected",
                     data: {
                         type: NODE_DESCRIPTIONS[ancestor.type] || ancestor.type
                     }
diff --git a/lib/rules/no-confusing-arrow.js b/lib/rules/no-confusing-arrow.js
index 542a4060e27..297e3b14808 100644
--- a/lib/rules/no-confusing-arrow.js
+++ b/lib/rules/no-confusing-arrow.js
@@ -42,7 +42,11 @@ module.exports = {
                 allowParens: { type: "boolean" }
             },
             additionalProperties: false
-        }]
+        }],
+
+        messages: {
+            confusing: "Arrow function used ambiguously with a conditional expression."
+        }
     },
 
     create(context) {
@@ -60,7 +64,7 @@ module.exports = {
             if (isConditional(body) && !(config.allowParens && astUtils.isParenthesised(sourceCode, body))) {
                 context.report({
                     node,
-                    message: "Arrow function used ambiguously with a conditional expression.",
+                    messageId: "confusing",
                     fix(fixer) {
 
                         // if `allowParens` is not set to true dont bother wrapping in parens
diff --git a/lib/rules/no-console.js b/lib/rules/no-console.js
index b00582ebada..fd5c33a8e79 100644
--- a/lib/rules/no-console.js
+++ b/lib/rules/no-console.js
@@ -39,7 +39,11 @@ module.exports = {
                 },
                 additionalProperties: false
             }
-        ]
+        ],
+
+        messages: {
+            unexpected: "Unexpected console statement."
+        }
     },
 
     create(context) {
@@ -102,7 +106,7 @@ module.exports = {
             context.report({
                 node,
                 loc: node.loc,
-                message: "Unexpected console statement."
+                messageId: "unexpected"
             });
         }
 
diff --git a/lib/rules/no-const-assign.js b/lib/rules/no-const-assign.js
index 8a08a52df4e..043fe05df72 100644
--- a/lib/rules/no-const-assign.js
+++ b/lib/rules/no-const-assign.js
@@ -20,7 +20,11 @@ module.exports = {
             url: "https://eslint.org/docs/rules/no-const-assign"
         },
 
-        schema: []
+        schema: [],
+
+        messages: {
+            const: "'{{name}}' is constant."
+        }
     },
 
     create(context) {
@@ -32,7 +36,7 @@ module.exports = {
          */
         function checkVariable(variable) {
             astUtils.getModifyingReferences(variable.references).forEach(reference => {
-                context.report({ node: reference.identifier, message: "'{{name}}' is constant.", data: { name: reference.identifier.name } });
+                context.report({ node: reference.identifier, messageId: "const", data: { name: reference.identifier.name } });
             });
         }
 
diff --git a/lib/rules/no-constant-condition.js b/lib/rules/no-constant-condition.js
index 5611d617ec8..724da974127 100644
--- a/lib/rules/no-constant-condition.js
+++ b/lib/rules/no-constant-condition.js
@@ -28,8 +28,11 @@ module.exports = {
                 },
                 additionalProperties: false
             }
+        ],
 
-        ]
+        messages: {
+            unexpected: "Unexpected constant condition."
+        }
     },
 
     create(context) {
@@ -139,7 +142,7 @@ module.exports = {
         function checkConstantConditionLoopInSet(node) {
             if (loopsInCurrentScope.has(node)) {
                 loopsInCurrentScope.delete(node);
-                context.report({ node: node.test, message: "Unexpected constant condition." });
+                context.report({ node: node.test, messageId: "unexpected" });
             }
         }
 
@@ -151,7 +154,7 @@ module.exports = {
          */
         function reportIfConstant(node) {
             if (node.test && isConstant(node.test, true)) {
-                context.report({ node: node.test, message: "Unexpected constant condition." });
+                context.report({ node: node.test, messageId: "unexpected" });
             }
         }
 
diff --git a/lib/rules/no-continue.js b/lib/rules/no-continue.js
index 52061ef5328..3075b77f9fd 100644
--- a/lib/rules/no-continue.js
+++ b/lib/rules/no-continue.js
@@ -18,14 +18,18 @@ module.exports = {
             url: "https://eslint.org/docs/rules/no-continue"
         },
 
-        schema: []
+        schema: [],
+
+        messages: {
+            unexpected: "Unexpected use of continue statement."
+        }
     },
 
     create(context) {
 
         return {
             ContinueStatement(node) {
-                context.report({ node, message: "Unexpected use of continue statement." });
+                context.report({ node, messageId: "unexpected" });
             }
         };
 
diff --git a/lib/rules/no-control-regex.js b/lib/rules/no-control-regex.js
index 676c666128e..e3afce787bd 100644
--- a/lib/rules/no-control-regex.js
+++ b/lib/rules/no-control-regex.js
@@ -18,7 +18,11 @@ module.exports = {
             url: "https://eslint.org/docs/rules/no-control-regex"
         },
 
-        schema: []
+        schema: [],
+
+        messages: {
+            unexpected: "Unexpected control character(s) in regular expression: {{controlChars}}."
+        }
     },
 
     create(context) {
@@ -26,7 +30,7 @@ module.exports = {
         /**
          * Get the regex expression
          * @param {ASTNode} node node to evaluate
-         * @returns {*} Regex if found else null
+         * @returns {RegExp|null} Regex if found else null
          * @private
          */
         function getRegExp(node) {
@@ -114,7 +118,7 @@ module.exports = {
                     if (controlCharacters.length > 0) {
                         context.report({
                             node,
-                            message: "Unexpected control character(s) in regular expression: {{controlChars}}.",
+                            messageId: "unexpected",
                             data: {
                                 controlChars: controlCharacters.join(", ")
                             }
diff --git a/lib/rules/no-debugger.js b/lib/rules/no-debugger.js
index 7d816e3a000..f00e819df09 100644
--- a/lib/rules/no-debugger.js
+++ b/lib/rules/no-debugger.js
@@ -20,7 +20,10 @@ module.exports = {
             url: "https://eslint.org/docs/rules/no-debugger"
         },
         fixable: "code",
-        schema: []
+        schema: [],
+        messages: {
+            unexpected: "Unexpected 'debugger' statement."
+        }
     },
 
     create(context) {
@@ -29,7 +32,7 @@ module.exports = {
             DebuggerStatement(node) {
                 context.report({
                     node,
-                    message: "Unexpected 'debugger' statement.",
+                    messageId: "unexpected",
                     fix(fixer) {
                         if (astUtils.STATEMENT_LIST_PARENTS.has(node.parent.type)) {
                             return fixer.remove(node);
diff --git a/lib/rules/no-delete-var.js b/lib/rules/no-delete-var.js
index 9ca09f1deae..f54a396ec2d 100644
--- a/lib/rules/no-delete-var.js
+++ b/lib/rules/no-delete-var.js
@@ -18,7 +18,11 @@ module.exports = {
             url: "https://eslint.org/docs/rules/no-delete-var"
         },
 
-        schema: []
+        schema: [],
+
+        messages: {
+            unexpected: "Variables should not be deleted."
+        }
     },
 
     create(context) {
@@ -27,7 +31,7 @@ module.exports = {
 
             UnaryExpression(node) {
                 if (node.operator === "delete" && node.argument.type === "Identifier") {
-                    context.report({ node, message: "Variables should not be deleted." });
+                    context.report({ node, messageId: "unexpected" });
                 }
             }
         };
diff --git a/lib/rules/no-div-regex.js b/lib/rules/no-div-regex.js
index 87423f8861a..c050249fd6e 100644
--- a/lib/rules/no-div-regex.js
+++ b/lib/rules/no-div-regex.js
@@ -18,7 +18,11 @@ module.exports = {
             url: "https://eslint.org/docs/rules/no-div-regex"
         },
 
-        schema: []
+        schema: [],
+
+        messages: {
+            unexpected: "A regular expression literal can be confused with '/='."
+        }
     },
 
     create(context) {
@@ -30,7 +34,7 @@ module.exports = {
                 const token = sourceCode.getFirstToken(node);
 
                 if (token.type === "RegularExpression" && token.value[1] === "=") {
-                    context.report({ node, message: "A regular expression literal can be confused with '/='." });
+                    context.report({ node, messageId: "unexpected" });
                 }
             }
         };
diff --git a/lib/rules/no-dupe-args.js b/lib/rules/no-dupe-args.js
index a71d01f9bd2..e5a7f4154e7 100644
--- a/lib/rules/no-dupe-args.js
+++ b/lib/rules/no-dupe-args.js
@@ -18,7 +18,11 @@ module.exports = {
             url: "https://eslint.org/docs/rules/no-dupe-args"
         },
 
-        schema: []
+        schema: [],
+
+        messages: {
+            unexpected: "Duplicate param '{{name}}'."
+        }
     },
 
     create(context) {
@@ -54,7 +58,7 @@ module.exports = {
                 if (defs.length >= 2) {
                     context.report({
                         node,
-                        message: "Duplicate param '{{name}}'.",
+                        messageId: "unexpected",
                         data: { name: variable.name }
                     });
                 }
diff --git a/lib/rules/no-dupe-class-members.js b/lib/rules/no-dupe-class-members.js
index cc7f8da284a..d0fc3597360 100644
--- a/lib/rules/no-dupe-class-members.js
+++ b/lib/rules/no-dupe-class-members.js
@@ -18,7 +18,11 @@ module.exports = {
             url: "https://eslint.org/docs/rules/no-dupe-class-members"
         },
 
-        schema: []
+        schema: [],
+
+        messages: {
+            unexpected: "Duplicate name '{{name}}'."
+        }
     },
 
     create(context) {
@@ -102,7 +106,7 @@ module.exports = {
                 }
 
                 if (isDuplicate) {
-                    context.report({ node, message: "Duplicate name '{{name}}'.", data: { name } });
+                    context.report({ node, messageId: "unexpected", data: { name } });
                 }
             }
         };
diff --git a/lib/rules/no-dupe-keys.js b/lib/rules/no-dupe-keys.js
index 10955e45037..577710c65d5 100644
--- a/lib/rules/no-dupe-keys.js
+++ b/lib/rules/no-dupe-keys.js
@@ -91,7 +91,11 @@ module.exports = {
             url: "https://eslint.org/docs/rules/no-dupe-keys"
         },
 
-        schema: []
+        schema: [],
+
+        messages: {
+            unexpected: "Duplicate key '{{name}}'."
+        }
     },
 
     create(context) {
@@ -123,7 +127,7 @@ module.exports = {
                     context.report({
                         node: info.node,
                         loc: node.key.loc,
-                        message: "Duplicate key '{{name}}'.",
+                        messageId: "unexpected",
                         data: { name }
                     });
                 }
diff --git a/lib/rules/no-duplicate-case.js b/lib/rules/no-duplicate-case.js
index 2a9d9551114..128b1fc1b1c 100644
--- a/lib/rules/no-duplicate-case.js
+++ b/lib/rules/no-duplicate-case.js
@@ -19,7 +19,11 @@ module.exports = {
             url: "https://eslint.org/docs/rules/no-duplicate-case"
         },
 
-        schema: []
+        schema: [],
+
+        messages: {
+            unexpected: "Duplicate case label."
+        }
     },
 
     create(context) {
@@ -33,7 +37,7 @@ module.exports = {
                     const key = sourceCode.getText(switchCase.test);
 
                     if (mapping[key]) {
-                        context.report({ node: switchCase, message: "Duplicate case label." });
+                        context.report({ node: switchCase, messageId: "unexpected" });
                     } else {
                         mapping[key] = switchCase;
                     }
diff --git a/lib/rules/no-else-return.js b/lib/rules/no-else-return.js
index 91cb5b97963..015ceddc4fc 100644
--- a/lib/rules/no-else-return.js
+++ b/lib/rules/no-else-return.js
@@ -34,7 +34,12 @@ module.exports = {
             },
             additionalProperties: false
         }],
-        fixable: "code"
+
+        fixable: "code",
+
+        messages: {
+            unexpected: "Unnecessary 'else' after 'return'."
+        }
     },
 
     create(context) {
@@ -52,7 +57,7 @@ module.exports = {
         function displayReport(node) {
             context.report({
                 node,
-                message: "Unnecessary 'else' after 'return'.",
+                messageId: "unexpected",
                 fix: fixer => {
                     const sourceCode = context.getSourceCode();
                     const startToken = sourceCode.getFirstToken(node);
diff --git a/lib/rules/no-empty-character-class.js b/lib/rules/no-empty-character-class.js
index 3c4806632e5..1f5c7333aa0 100644
--- a/lib/rules/no-empty-character-class.js
+++ b/lib/rules/no-empty-character-class.js
@@ -36,7 +36,11 @@ module.exports = {
             url: "https://eslint.org/docs/rules/no-empty-character-class"
         },
 
-        schema: []
+        schema: [],
+
+        messages: {
+            unexpected: "Empty class."
+        }
     },
 
     create(context) {
@@ -48,7 +52,7 @@ module.exports = {
                 const token = sourceCode.getFirstToken(node);
 
                 if (token.type === "RegularExpression" && !regex.test(token.value)) {
-                    context.report({ node, message: "Empty class." });
+                    context.report({ node, messageId: "unexpected" });
                 }
             }
 
diff --git a/lib/rules/no-empty-function.js b/lib/rules/no-empty-function.js
index 3852774e6b2..d9948cd4a33 100644
--- a/lib/rules/no-empty-function.js
+++ b/lib/rules/no-empty-function.js
@@ -109,7 +109,11 @@ module.exports = {
                 },
                 additionalProperties: false
             }
-        ]
+        ],
+
+        messages: {
+            unexpected: "Unexpected empty {{name}}."
+        }
     },
 
     create(context) {
@@ -146,7 +150,7 @@ module.exports = {
                 context.report({
                     node,
                     loc: node.body.loc.start,
-                    message: "Unexpected empty {{name}}.",
+                    messageId: "unexpected",
                     data: { name }
                 });
             }
diff --git a/lib/rules/no-empty-pattern.js b/lib/rules/no-empty-pattern.js
index 1d0c3ab4b1d..939710560fa 100644
--- a/lib/rules/no-empty-pattern.js
+++ b/lib/rules/no-empty-pattern.js
@@ -17,19 +17,23 @@ module.exports = {
             url: "https://eslint.org/docs/rules/no-empty-pattern"
         },
 
-        schema: []
+        schema: [],
+
+        messages: {
+            unexpected: "Unexpected empty {{type}} pattern."
+        }
     },
 
     create(context) {
         return {
             ObjectPattern(node) {
                 if (node.properties.length === 0) {
-                    context.report({ node, message: "Unexpected empty object pattern." });
+                    context.report({ node, messageId: "unexpected", data: { type: "object" } });
                 }
             },
             ArrayPattern(node) {
                 if (node.elements.length === 0) {
-                    context.report({ node, message: "Unexpected empty array pattern." });
+                    context.report({ node, messageId: "unexpected", data: { type: "array" } });
                 }
             }
         };
diff --git a/lib/rules/no-empty.js b/lib/rules/no-empty.js
index 15f1df67908..a598d40f8ca 100644
--- a/lib/rules/no-empty.js
+++ b/lib/rules/no-empty.js
@@ -33,7 +33,11 @@ module.exports = {
                 },
                 additionalProperties: false
             }
-        ]
+        ],
+
+        messages: {
+            unexpected: "Empty {{type}} statement."
+        }
     },
 
     create(context) {
@@ -64,13 +68,13 @@ module.exports = {
                     return;
                 }
 
-                context.report({ node, message: "Empty block statement." });
+                context.report({ node, messageId: "unexpected", data: { type: "block" } });
             },
 
             SwitchStatement(node) {
 
                 if (typeof node.cases === "undefined" || node.cases.length === 0) {
-                    context.report({ node, message: "Empty switch statement." });
+                    context.report({ node, messageId: "unexpected", data: { type: "switch" } });
                 }
             }
         };
diff --git a/lib/rules/no-eq-null.js b/lib/rules/no-eq-null.js
index 22dbd49d421..eadd16de37f 100644
--- a/lib/rules/no-eq-null.js
+++ b/lib/rules/no-eq-null.js
@@ -19,7 +19,11 @@ module.exports = {
             url: "https://eslint.org/docs/rules/no-eq-null"
         },
 
-        schema: []
+        schema: [],
+
+        messages: {
+            unexpected: "Use '===' to compare with null."
+        }
     },
 
     create(context) {
@@ -31,7 +35,7 @@ module.exports = {
 
                 if (node.right.type === "Literal" && node.right.raw === "null" && badOperator ||
                         node.left.type === "Literal" && node.left.raw === "null" && badOperator) {
-                    context.report({ node, message: "Use '===' to compare with null." });
+                    context.report({ node, messageId: "unexpected" });
                 }
             }
         };
diff --git a/lib/rules/no-eval.js b/lib/rules/no-eval.js
index 8cf4aa307b0..f77451ec381 100644
--- a/lib/rules/no-eval.js
+++ b/lib/rules/no-eval.js
@@ -91,7 +91,11 @@ module.exports = {
                 },
                 additionalProperties: false
             }
-        ]
+        ],
+
+        messages: {
+            unexpected: "eval can be harmful."
+        }
     },
 
     create(context) {
@@ -160,7 +164,7 @@ module.exports = {
             context.report({
                 node,
                 loc: locationNode.loc.start,
-                message: "eval can be harmful."
+                messageId: "unexpected"
             });
         }
 
diff --git a/lib/rules/no-ex-assign.js b/lib/rules/no-ex-assign.js
index 6ede2fc210b..feace415e50 100644
--- a/lib/rules/no-ex-assign.js
+++ b/lib/rules/no-ex-assign.js
@@ -20,7 +20,11 @@ module.exports = {
             url: "https://eslint.org/docs/rules/no-ex-assign"
         },
 
-        schema: []
+        schema: [],
+
+        messages: {
+            unexpected: "Do not assign to the exception parameter."
+        }
     },
 
     create(context) {
@@ -32,7 +36,7 @@ module.exports = {
          */
         function checkVariable(variable) {
             astUtils.getModifyingReferences(variable.references).forEach(reference => {
-                context.report({ node: reference.identifier, message: "Do not assign to the exception parameter." });
+                context.report({ node: reference.identifier, messageId: "unexpected" });
             });
         }
 
diff --git a/lib/rules/no-extend-native.js b/lib/rules/no-extend-native.js
index 2e170017a87..3ba13090a67 100644
--- a/lib/rules/no-extend-native.js
+++ b/lib/rules/no-extend-native.js
@@ -45,7 +45,11 @@ module.exports = {
                 },
                 additionalProperties: false
             }
-        ]
+        ],
+
+        messages: {
+            unexpected: "{{builtin}} prototype is read only, properties should not be added."
+        }
     },
 
     create(context) {
@@ -67,7 +71,7 @@ module.exports = {
         function reportNode(node, builtin) {
             context.report({
                 node,
-                message: "{{builtin}} prototype is read only, properties should not be added.",
+                messageId: "unexpected",
                 data: {
                     builtin
                 }
diff --git a/lib/rules/no-extra-bind.js b/lib/rules/no-extra-bind.js
index 21b96c3c261..8d901808fd6 100644
--- a/lib/rules/no-extra-bind.js
+++ b/lib/rules/no-extra-bind.js
@@ -25,7 +25,11 @@ module.exports = {
 
         schema: [],
 
-        fixable: "code"
+        fixable: "code",
+
+        messages: {
+            unexpected: "The function binding is unnecessary."
+        }
     },
 
     create(context) {
@@ -41,7 +45,7 @@ module.exports = {
         function report(node) {
             context.report({
                 node: node.parent.parent,
-                message: "The function binding is unnecessary.",
+                messageId: "unexpected",
                 loc: node.parent.property.loc.start,
                 fix(fixer) {
                     const firstTokenToRemove = context.getSourceCode()
diff --git a/lib/rules/no-extra-boolean-cast.js b/lib/rules/no-extra-boolean-cast.js
index 471e8b5b82c..38191361715 100644
--- a/lib/rules/no-extra-boolean-cast.js
+++ b/lib/rules/no-extra-boolean-cast.js
@@ -26,7 +26,12 @@ module.exports = {
 
         schema: [],
 
-        fixable: "code"
+        fixable: "code",
+
+        messages: {
+            unexpectedCall: "Redundant Boolean call.",
+            unexpectedNegation: "Redundant double negation."
+        }
     },
 
     create(context) {
@@ -82,7 +87,7 @@ module.exports = {
                 ) {
                     context.report({
                         node,
-                        message: "Redundant double negation.",
+                        messageId: "unexpectedNegation",
                         fix: fixer => fixer.replaceText(parent, sourceCode.getText(node.argument))
                     });
                 }
@@ -97,7 +102,7 @@ module.exports = {
                 if (isInBooleanContext(node, parent)) {
                     context.report({
                         node,
-                        message: "Redundant Boolean call.",
+                        messageId: "unexpectedCall",
                         fix: fixer => {
                             if (!node.arguments.length) {
                                 return fixer.replaceText(parent, "true");
diff --git a/lib/rules/no-extra-label.js b/lib/rules/no-extra-label.js
index f90a403cbfd..73a3fea9c96 100644
--- a/lib/rules/no-extra-label.js
+++ b/lib/rules/no-extra-label.js
@@ -26,7 +26,11 @@ module.exports = {
 
         schema: [],
 
-        fixable: "code"
+        fixable: "code",
+
+        messages: {
+            unexpected: "This label '{{name}}' is unnecessary."
+        }
     },
 
     create(context) {
@@ -109,7 +113,7 @@ module.exports = {
                     if (info.breakable && info.label && info.label.name === labelNode.name) {
                         context.report({
                             node: labelNode,
-                            message: "This label '{{name}}' is unnecessary.",
+                            messageId: "unexpected",
                             data: labelNode,
                             fix: fixer => fixer.removeRange([sourceCode.getFirstToken(node).range[1], labelNode.range[1]])
                         });
diff --git a/lib/rules/no-extra-parens.js b/lib/rules/no-extra-parens.js
index 4bf8f995009..daf069e9b9f 100644
--- a/lib/rules/no-extra-parens.js
+++ b/lib/rules/no-extra-parens.js
@@ -55,6 +55,10 @@ module.exports = {
                     maxItems: 2
                 }
             ]
+        },
+
+        messages: {
+            unexpected: "Gratuitous parentheses around expression."
         }
     },
 
@@ -312,7 +316,7 @@ module.exports = {
             context.report({
                 node,
                 loc: leftParenToken.loc.start,
-                message: "Gratuitous parentheses around expression.",
+                messageId: "unexpected",
                 fix(fixer) {
                     const parenthesizedSource = sourceCode.text.slice(leftParenToken.range[1], rightParenToken.range[0]);
 
diff --git a/lib/rules/no-extra-semi.js b/lib/rules/no-extra-semi.js
index 5668c7e095e..a0741088589 100644
--- a/lib/rules/no-extra-semi.js
+++ b/lib/rules/no-extra-semi.js
@@ -26,7 +26,11 @@ module.exports = {
         },
 
         fixable: "code",
-        schema: []
+        schema: [],
+
+        messages: {
+            unexpected: "Unnecessary semicolon."
+        }
     },
 
     create(context) {
@@ -40,7 +44,7 @@ module.exports = {
         function report(nodeOrToken) {
             context.report({
                 node: nodeOrToken,
-                message: "Unnecessary semicolon.",
+                messageId: "unexpected",
                 fix(fixer) {
 
                     /*
diff --git a/tests/lib/cli-engine.js b/tests/lib/cli-engine.js
index 48bc82f10b8..e267ed3b2af 100644
--- a/tests/lib/cli-engine.js
+++ b/tests/lib/cli-engine.js
@@ -1395,6 +1395,7 @@ describe("CLIEngine", () => {
                                     column: 9,
                                     line: 2,
                                     message: "Expected '===' and instead saw '=='.",
+                                    messageId: "unexpected",
                                     nodeType: "BinaryExpression",
                                     ruleId: "eqeqeq",
                                     severity: 2,
diff --git a/tests/lib/rules/accessor-pairs.js b/tests/lib/rules/accessor-pairs.js
index f694707fd18..6470324f998 100644
--- a/tests/lib/rules/accessor-pairs.js
+++ b/tests/lib/rules/accessor-pairs.js
@@ -18,6 +18,9 @@ const rule = require("../../../lib/rules/accessor-pairs"),
 
 const ruleTester = new RuleTester();
 
+const getterError = { messageId: "getter" };
+const setterError = { messageId: "setter" };
+
 ruleTester.run("accessor-pairs", rule, {
     valid: [
         "var o = { a: 1 };",
@@ -46,49 +49,35 @@ ruleTester.run("accessor-pairs", rule, {
     invalid: [
         {
             code: "var o = {\n set a(value) {\n val = value; \n} \n};",
-            errors: [{
-                message: "Getter is not present."
-            }]
+            errors: [getterError]
         },
         {
             code: "var o = {\n get a() {\n return val; \n} \n};",
             options: [{
                 getWithoutSet: true
             }],
-            errors: [{
-                message: "Setter is not present."
-            }]
+            errors: [setterError]
         },
         {
             code: "var o = {d: 1};\n Object.defineProperty(o, 'c', \n{set: function(value) {\n val = value; \n} \n});",
-            errors: [{
-                message: "Getter is not present."
-            }]
+            errors: [getterError]
         },
         {
             code: "Reflect.defineProperty(obj, 'foo', {set: function(value) {}});",
-            errors: [{
-                message: "Getter is not present."
-            }]
+            errors: [getterError]
         },
         {
             code: "Object.defineProperties(obj, {foo: {set: function(value) {}}});",
-            errors: [{
-                message: "Getter is not present."
-            }]
+            errors: [getterError]
         },
         {
             code: "Object.create(null, {foo: {set: function(value) {}}});",
-            errors: [{
-                message: "Getter is not present."
-            }]
+            errors: [getterError]
         },
         {
             code: "var expr = 'foo';  var o = { set [expr](value) { val = value; } };",
             parserOptions: { ecmaVersion: 6 },
-            errors: [{
-                message: "Getter is not present."
-            }]
+            errors: [getterError]
         }
     ]
 });
diff --git a/tests/lib/rules/array-bracket-newline.js b/tests/lib/rules/array-bracket-newline.js
index 86eee8fba3b..bde0f56a227 100644
--- a/tests/lib/rules/array-bracket-newline.js
+++ b/tests/lib/rules/array-bracket-newline.js
@@ -19,11 +19,6 @@ const RuleTester = require("../../../lib/testers/rule-tester");
 
 const ruleTester = new RuleTester();
 
-const ERR_NO_BREAK_AFTER = "There should be no linebreak after '['.";
-const ERR_BREAK_AFTER = "A linebreak is required after '['.";
-const ERR_NO_BREAK_BEFORE = "There should be no linebreak before ']'.";
-const ERR_BREAK_BEFORE = "A linebreak is required before ']'.";
-
 ruleTester.run("array-bracket-newline", rule, {
 
     valid: [
@@ -187,7 +182,7 @@ ruleTester.run("array-bracket-newline", rule, {
             options: ["always"],
             errors: [
                 {
-                    message: ERR_BREAK_AFTER,
+                    messageId: "missingOpeningLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 11,
@@ -195,7 +190,7 @@ ruleTester.run("array-bracket-newline", rule, {
                     endColumn: 12
                 },
                 {
-                    message: ERR_BREAK_BEFORE,
+                    messageId: "missingClosingLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 12,
@@ -210,13 +205,13 @@ ruleTester.run("array-bracket-newline", rule, {
             options: ["always"],
             errors: [
                 {
-                    message: ERR_BREAK_AFTER,
+                    messageId: "missingOpeningLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
                 },
                 {
-                    message: ERR_BREAK_BEFORE,
+                    messageId: "missingClosingLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 13
@@ -229,7 +224,7 @@ ruleTester.run("array-bracket-newline", rule, {
             options: ["always"],
             errors: [
                 {
-                    message: ERR_BREAK_BEFORE,
+                    messageId: "missingClosingLinebreak",
                     type: "ArrayExpression",
                     line: 2,
                     column: 2,
@@ -244,7 +239,7 @@ ruleTester.run("array-bracket-newline", rule, {
             options: ["always"],
             errors: [
                 {
-                    message: ERR_BREAK_BEFORE,
+                    messageId: "missingClosingLinebreak",
                     type: "ArrayExpression",
                     line: 2,
                     column: 2
@@ -257,7 +252,7 @@ ruleTester.run("array-bracket-newline", rule, {
             options: ["always"],
             errors: [
                 {
-                    message: ERR_BREAK_AFTER,
+                    messageId: "missingOpeningLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 11,
@@ -265,7 +260,7 @@ ruleTester.run("array-bracket-newline", rule, {
                     endColumn: 12
                 },
                 {
-                    message: ERR_BREAK_BEFORE,
+                    messageId: "missingClosingLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 16,
@@ -280,7 +275,7 @@ ruleTester.run("array-bracket-newline", rule, {
             options: ["always"],
             errors: [
                 {
-                    message: ERR_BREAK_AFTER,
+                    messageId: "missingOpeningLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
@@ -293,13 +288,13 @@ ruleTester.run("array-bracket-newline", rule, {
             options: ["always"],
             errors: [
                 {
-                    message: ERR_BREAK_AFTER,
+                    messageId: "missingOpeningLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
                 },
                 {
-                    message: ERR_BREAK_BEFORE,
+                    messageId: "missingClosingLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 34
@@ -312,13 +307,13 @@ ruleTester.run("array-bracket-newline", rule, {
             options: ["always"],
             errors: [
                 {
-                    message: ERR_BREAK_AFTER,
+                    messageId: "missingOpeningLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
                 },
                 {
-                    message: ERR_BREAK_BEFORE,
+                    messageId: "missingClosingLinebreak",
                     type: "ArrayExpression",
                     line: 2,
                     column: 2
@@ -331,13 +326,13 @@ ruleTester.run("array-bracket-newline", rule, {
             options: ["always"],
             errors: [
                 {
-                    message: ERR_BREAK_AFTER,
+                    messageId: "missingOpeningLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
                 },
                 {
-                    message: ERR_BREAK_BEFORE,
+                    messageId: "missingClosingLinebreak",
                     type: "ArrayExpression",
                     line: 3,
                     column: 2
@@ -352,13 +347,13 @@ ruleTester.run("array-bracket-newline", rule, {
             options: ["never"],
             errors: [
                 {
-                    message: ERR_NO_BREAK_AFTER,
+                    messageId: "unexpectedOpeningLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
                 },
                 {
-                    message: ERR_NO_BREAK_BEFORE,
+                    messageId: "unexpectedClosingLinebreak",
                     type: "ArrayExpression",
                     line: 2,
                     column: 1
@@ -371,7 +366,7 @@ ruleTester.run("array-bracket-newline", rule, {
             options: ["never"],
             errors: [
                 {
-                    message: ERR_NO_BREAK_AFTER,
+                    messageId: "unexpectedOpeningLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 11,
@@ -379,7 +374,7 @@ ruleTester.run("array-bracket-newline", rule, {
                     endColumn: 12
                 },
                 {
-                    message: ERR_NO_BREAK_BEFORE,
+                    messageId: "unexpectedClosingLinebreak",
                     type: "ArrayExpression",
                     line: 3,
                     column: 1,
@@ -394,13 +389,13 @@ ruleTester.run("array-bracket-newline", rule, {
             options: ["never"],
             errors: [
                 {
-                    message: ERR_NO_BREAK_AFTER,
+                    messageId: "unexpectedOpeningLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
                 },
                 {
-                    message: ERR_NO_BREAK_BEFORE,
+                    messageId: "unexpectedClosingLinebreak",
                     type: "ArrayExpression",
                     line: 3,
                     column: 1
@@ -413,13 +408,13 @@ ruleTester.run("array-bracket-newline", rule, {
             options: ["never"],
             errors: [
                 {
-                    message: ERR_NO_BREAK_AFTER,
+                    messageId: "unexpectedOpeningLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
                 },
                 {
-                    message: ERR_NO_BREAK_BEFORE,
+                    messageId: "unexpectedClosingLinebreak",
                     type: "ArrayExpression",
                     line: 3,
                     column: 1
@@ -432,13 +427,13 @@ ruleTester.run("array-bracket-newline", rule, {
             options: ["never"],
             errors: [
                 {
-                    message: ERR_NO_BREAK_AFTER,
+                    messageId: "unexpectedOpeningLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
                 },
                 {
-                    message: ERR_NO_BREAK_BEFORE,
+                    messageId: "unexpectedClosingLinebreak",
                     type: "ArrayExpression",
                     line: 3,
                     column: 18
@@ -451,13 +446,13 @@ ruleTester.run("array-bracket-newline", rule, {
             options: ["never"],
             errors: [
                 {
-                    message: ERR_NO_BREAK_AFTER,
+                    messageId: "unexpectedOpeningLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
                 },
                 {
-                    message: ERR_NO_BREAK_BEFORE,
+                    messageId: "unexpectedClosingLinebreak",
                     type: "ArrayExpression",
                     line: 3,
                     column: 1
@@ -470,13 +465,13 @@ ruleTester.run("array-bracket-newline", rule, {
             options: ["never"],
             errors: [
                 {
-                    message: ERR_NO_BREAK_AFTER,
+                    messageId: "unexpectedOpeningLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
                 },
                 {
-                    message: ERR_NO_BREAK_BEFORE,
+                    messageId: "unexpectedClosingLinebreak",
                     type: "ArrayExpression",
                     line: 4,
                     column: 1
@@ -489,13 +484,13 @@ ruleTester.run("array-bracket-newline", rule, {
             options: ["never"],
             errors: [
                 {
-                    message: ERR_NO_BREAK_AFTER,
+                    messageId: "unexpectedOpeningLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
                 },
                 {
-                    message: ERR_NO_BREAK_BEFORE,
+                    messageId: "unexpectedClosingLinebreak",
                     type: "ArrayExpression",
                     line: 5,
                     column: 1
@@ -510,7 +505,7 @@ ruleTester.run("array-bracket-newline", rule, {
             options: ["consistent"],
             errors: [
                 {
-                    message: ERR_BREAK_BEFORE,
+                    messageId: "missingClosingLinebreak",
                     type: "ArrayExpression",
                     line: 2,
                     column: 2,
@@ -525,7 +520,7 @@ ruleTester.run("array-bracket-newline", rule, {
             options: ["consistent"],
             errors: [
                 {
-                    message: ERR_NO_BREAK_BEFORE,
+                    messageId: "unexpectedClosingLinebreak",
                     type: "ArrayExpression",
                     line: 2,
                     column: 1,
@@ -542,13 +537,13 @@ ruleTester.run("array-bracket-newline", rule, {
             options: [{ multiline: true }],
             errors: [
                 {
-                    message: ERR_NO_BREAK_AFTER,
+                    messageId: "unexpectedOpeningLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
                 },
                 {
-                    message: ERR_NO_BREAK_BEFORE,
+                    messageId: "unexpectedClosingLinebreak",
                     type: "ArrayExpression",
                     line: 2,
                     column: 1
@@ -561,13 +556,13 @@ ruleTester.run("array-bracket-newline", rule, {
             options: [{ multiline: true }],
             errors: [
                 {
-                    message: ERR_NO_BREAK_AFTER,
+                    messageId: "unexpectedOpeningLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
                 },
                 {
-                    message: ERR_NO_BREAK_BEFORE,
+                    messageId: "unexpectedClosingLinebreak",
                     type: "ArrayExpression",
                     line: 3,
                     column: 1
@@ -580,13 +575,13 @@ ruleTester.run("array-bracket-newline", rule, {
             options: [{ multiline: true }],
             errors: [
                 {
-                    message: ERR_NO_BREAK_AFTER,
+                    messageId: "unexpectedOpeningLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
                 },
                 {
-                    message: ERR_NO_BREAK_BEFORE,
+                    messageId: "unexpectedClosingLinebreak",
                     type: "ArrayExpression",
                     line: 3,
                     column: 1
@@ -599,13 +594,13 @@ ruleTester.run("array-bracket-newline", rule, {
             options: [{ multiline: true }],
             errors: [
                 {
-                    message: ERR_NO_BREAK_AFTER,
+                    messageId: "unexpectedOpeningLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
                 },
                 {
-                    message: ERR_NO_BREAK_BEFORE,
+                    messageId: "unexpectedClosingLinebreak",
                     type: "ArrayExpression",
                     line: 3,
                     column: 1
@@ -618,13 +613,13 @@ ruleTester.run("array-bracket-newline", rule, {
             options: [{ multiline: true }],
             errors: [
                 {
-                    message: ERR_BREAK_AFTER,
+                    messageId: "missingOpeningLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
                 },
                 {
-                    message: ERR_BREAK_BEFORE,
+                    messageId: "missingClosingLinebreak",
                     type: "ArrayExpression",
                     line: 2,
                     column: 2
@@ -637,13 +632,13 @@ ruleTester.run("array-bracket-newline", rule, {
             options: [{ multiline: true }],
             errors: [
                 {
-                    message: ERR_BREAK_AFTER,
+                    messageId: "missingOpeningLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
                 },
                 {
-                    message: ERR_BREAK_BEFORE,
+                    messageId: "missingClosingLinebreak",
                     type: "ArrayExpression",
                     line: 3,
                     column: 2
@@ -658,13 +653,13 @@ ruleTester.run("array-bracket-newline", rule, {
             options: [{ minItems: 2 }],
             errors: [
                 {
-                    message: ERR_NO_BREAK_AFTER,
+                    messageId: "unexpectedOpeningLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
                 },
                 {
-                    message: ERR_NO_BREAK_BEFORE,
+                    messageId: "unexpectedClosingLinebreak",
                     type: "ArrayExpression",
                     line: 2,
                     column: 1
@@ -677,13 +672,13 @@ ruleTester.run("array-bracket-newline", rule, {
             options: [{ minItems: 2 }],
             errors: [
                 {
-                    message: ERR_NO_BREAK_AFTER,
+                    messageId: "unexpectedOpeningLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
                 },
                 {
-                    message: ERR_NO_BREAK_BEFORE,
+                    messageId: "unexpectedClosingLinebreak",
                     type: "ArrayExpression",
                     line: 3,
                     column: 1
@@ -696,13 +691,13 @@ ruleTester.run("array-bracket-newline", rule, {
             options: [{ minItems: 2 }],
             errors: [
                 {
-                    message: ERR_BREAK_AFTER,
+                    messageId: "missingOpeningLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
                 },
                 {
-                    message: ERR_BREAK_BEFORE,
+                    messageId: "missingClosingLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 16
@@ -715,13 +710,13 @@ ruleTester.run("array-bracket-newline", rule, {
             options: [{ minItems: 2 }],
             errors: [
                 {
-                    message: ERR_BREAK_AFTER,
+                    messageId: "missingOpeningLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
                 },
                 {
-                    message: ERR_BREAK_BEFORE,
+                    messageId: "missingClosingLinebreak",
                     type: "ArrayExpression",
                     line: 2,
                     column: 2
@@ -734,13 +729,13 @@ ruleTester.run("array-bracket-newline", rule, {
             options: [{ minItems: 2 }],
             errors: [
                 {
-                    message: ERR_NO_BREAK_AFTER,
+                    messageId: "unexpectedOpeningLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
                 },
                 {
-                    message: ERR_NO_BREAK_BEFORE,
+                    messageId: "unexpectedClosingLinebreak",
                     type: "ArrayExpression",
                     line: 5,
                     column: 1
@@ -755,13 +750,13 @@ ruleTester.run("array-bracket-newline", rule, {
             options: [{ minItems: 0 }],
             errors: [
                 {
-                    message: ERR_BREAK_AFTER,
+                    messageId: "missingOpeningLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
                 },
                 {
-                    message: ERR_BREAK_BEFORE,
+                    messageId: "missingClosingLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 12
@@ -774,13 +769,13 @@ ruleTester.run("array-bracket-newline", rule, {
             options: [{ minItems: 0 }],
             errors: [
                 {
-                    message: ERR_BREAK_AFTER,
+                    messageId: "missingOpeningLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
                 },
                 {
-                    message: ERR_BREAK_BEFORE,
+                    messageId: "missingClosingLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 13
@@ -793,13 +788,13 @@ ruleTester.run("array-bracket-newline", rule, {
             options: [{ minItems: 0 }],
             errors: [
                 {
-                    message: ERR_BREAK_AFTER,
+                    messageId: "missingOpeningLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
                 },
                 {
-                    message: ERR_BREAK_BEFORE,
+                    messageId: "missingClosingLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 16
@@ -812,13 +807,13 @@ ruleTester.run("array-bracket-newline", rule, {
             options: [{ minItems: 0 }],
             errors: [
                 {
-                    message: ERR_BREAK_AFTER,
+                    messageId: "missingOpeningLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
                 },
                 {
-                    message: ERR_BREAK_BEFORE,
+                    messageId: "missingClosingLinebreak",
                     type: "ArrayExpression",
                     line: 2,
                     column: 2
@@ -832,13 +827,13 @@ ruleTester.run("array-bracket-newline", rule, {
             options: [{ minItems: 0 }],
             errors: [
                 {
-                    message: ERR_BREAK_AFTER,
+                    messageId: "missingOpeningLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
                 },
                 {
-                    message: ERR_BREAK_BEFORE,
+                    messageId: "missingClosingLinebreak",
                     type: "ArrayExpression",
                     line: 3,
                     column: 2
@@ -853,13 +848,13 @@ ruleTester.run("array-bracket-newline", rule, {
             options: [{ minItems: null }],
             errors: [
                 {
-                    message: ERR_NO_BREAK_AFTER,
+                    messageId: "unexpectedOpeningLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
                 },
                 {
-                    message: ERR_NO_BREAK_BEFORE,
+                    messageId: "unexpectedClosingLinebreak",
                     type: "ArrayExpression",
                     line: 2,
                     column: 1
@@ -872,13 +867,13 @@ ruleTester.run("array-bracket-newline", rule, {
             options: [{ minItems: null }],
             errors: [
                 {
-                    message: ERR_NO_BREAK_AFTER,
+                    messageId: "unexpectedOpeningLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
                 },
                 {
-                    message: ERR_NO_BREAK_BEFORE,
+                    messageId: "unexpectedClosingLinebreak",
                     type: "ArrayExpression",
                     line: 3,
                     column: 1
@@ -891,13 +886,13 @@ ruleTester.run("array-bracket-newline", rule, {
             options: [{ minItems: null }],
             errors: [
                 {
-                    message: ERR_NO_BREAK_AFTER,
+                    messageId: "unexpectedOpeningLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
                 },
                 {
-                    message: ERR_NO_BREAK_BEFORE,
+                    messageId: "unexpectedClosingLinebreak",
                     type: "ArrayExpression",
                     line: 3,
                     column: 1
@@ -910,13 +905,13 @@ ruleTester.run("array-bracket-newline", rule, {
             options: [{ minItems: null }],
             errors: [
                 {
-                    message: ERR_NO_BREAK_AFTER,
+                    messageId: "unexpectedOpeningLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
                 },
                 {
-                    message: ERR_NO_BREAK_BEFORE,
+                    messageId: "unexpectedClosingLinebreak",
                     type: "ArrayExpression",
                     line: 4,
                     column: 1
@@ -929,13 +924,13 @@ ruleTester.run("array-bracket-newline", rule, {
             options: [{ minItems: null }],
             errors: [
                 {
-                    message: ERR_NO_BREAK_AFTER,
+                    messageId: "unexpectedOpeningLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
                 },
                 {
-                    message: ERR_NO_BREAK_BEFORE,
+                    messageId: "unexpectedClosingLinebreak",
                     type: "ArrayExpression",
                     line: 5,
                     column: 1
@@ -950,13 +945,13 @@ ruleTester.run("array-bracket-newline", rule, {
             options: [{ multiline: true, minItems: null }],
             errors: [
                 {
-                    message: ERR_NO_BREAK_AFTER,
+                    messageId: "unexpectedOpeningLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
                 },
                 {
-                    message: ERR_NO_BREAK_BEFORE,
+                    messageId: "unexpectedClosingLinebreak",
                     type: "ArrayExpression",
                     line: 2,
                     column: 1
@@ -969,13 +964,13 @@ ruleTester.run("array-bracket-newline", rule, {
             options: [{ multiline: true, minItems: null }],
             errors: [
                 {
-                    message: ERR_NO_BREAK_AFTER,
+                    messageId: "unexpectedOpeningLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
                 },
                 {
-                    message: ERR_NO_BREAK_BEFORE,
+                    messageId: "unexpectedClosingLinebreak",
                     type: "ArrayExpression",
                     line: 3,
                     column: 1
@@ -988,13 +983,13 @@ ruleTester.run("array-bracket-newline", rule, {
             options: [{ multiline: true, minItems: null }],
             errors: [
                 {
-                    message: ERR_NO_BREAK_AFTER,
+                    messageId: "unexpectedOpeningLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
                 },
                 {
-                    message: ERR_NO_BREAK_BEFORE,
+                    messageId: "unexpectedClosingLinebreak",
                     type: "ArrayExpression",
                     line: 3,
                     column: 1
@@ -1007,13 +1002,13 @@ ruleTester.run("array-bracket-newline", rule, {
             options: [{ multiline: true, minItems: null }],
             errors: [
                 {
-                    message: ERR_BREAK_AFTER,
+                    messageId: "missingOpeningLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
                 },
                 {
-                    message: ERR_BREAK_BEFORE,
+                    messageId: "missingClosingLinebreak",
                     type: "ArrayExpression",
                     line: 2,
                     column: 2
@@ -1026,13 +1021,13 @@ ruleTester.run("array-bracket-newline", rule, {
             options: [{ multiline: true, minItems: null }],
             errors: [
                 {
-                    message: ERR_BREAK_AFTER,
+                    messageId: "missingOpeningLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
                 },
                 {
-                    message: ERR_BREAK_BEFORE,
+                    messageId: "missingClosingLinebreak",
                     type: "ArrayExpression",
                     line: 3,
                     column: 2
@@ -1047,13 +1042,13 @@ ruleTester.run("array-bracket-newline", rule, {
             options: [{ multiline: true, minItems: 2 }],
             errors: [
                 {
-                    message: ERR_NO_BREAK_AFTER,
+                    messageId: "unexpectedOpeningLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
                 },
                 {
-                    message: ERR_NO_BREAK_BEFORE,
+                    messageId: "unexpectedClosingLinebreak",
                     type: "ArrayExpression",
                     line: 2,
                     column: 1
@@ -1066,13 +1061,13 @@ ruleTester.run("array-bracket-newline", rule, {
             options: [{ multiline: true, minItems: 2 }],
             errors: [
                 {
-                    message: ERR_NO_BREAK_AFTER,
+                    messageId: "unexpectedOpeningLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
                 },
                 {
-                    message: ERR_NO_BREAK_BEFORE,
+                    messageId: "unexpectedClosingLinebreak",
                     type: "ArrayExpression",
                     line: 3,
                     column: 1
@@ -1085,13 +1080,13 @@ ruleTester.run("array-bracket-newline", rule, {
             options: [{ multiline: true, minItems: 2 }],
             errors: [
                 {
-                    message: ERR_BREAK_AFTER,
+                    messageId: "missingOpeningLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
                 },
                 {
-                    message: ERR_BREAK_BEFORE,
+                    messageId: "missingClosingLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 16
@@ -1104,13 +1099,13 @@ ruleTester.run("array-bracket-newline", rule, {
             options: [{ multiline: true, minItems: 2 }],
             errors: [
                 {
-                    message: ERR_BREAK_AFTER,
+                    messageId: "missingOpeningLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
                 },
                 {
-                    message: ERR_BREAK_BEFORE,
+                    messageId: "missingClosingLinebreak",
                     type: "ArrayExpression",
                     line: 2,
                     column: 2
@@ -1123,13 +1118,13 @@ ruleTester.run("array-bracket-newline", rule, {
             options: [{ multiline: true, minItems: 2 }],
             errors: [
                 {
-                    message: ERR_BREAK_AFTER,
+                    messageId: "missingOpeningLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
                 },
                 {
-                    message: ERR_BREAK_BEFORE,
+                    messageId: "missingClosingLinebreak",
                     type: "ArrayExpression",
                     line: 3,
                     column: 2
@@ -1147,7 +1142,7 @@ ruleTester.run("array-bracket-newline", rule, {
             options: ["always"],
             errors: [
                 {
-                    message: ERR_BREAK_BEFORE,
+                    messageId: "missingClosingLinebreak",
                     type: "ArrayExpression",
                     line: 2,
                     column: 5
@@ -1160,13 +1155,13 @@ ruleTester.run("array-bracket-newline", rule, {
             options: ["always"],
             errors: [
                 {
-                    message: ERR_BREAK_AFTER,
+                    messageId: "missingOpeningLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
                 },
                 {
-                    message: ERR_BREAK_BEFORE,
+                    messageId: "missingClosingLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 17
@@ -1179,7 +1174,7 @@ ruleTester.run("array-bracket-newline", rule, {
             options: ["always"],
             errors: [
                 {
-                    message: ERR_BREAK_AFTER,
+                    messageId: "missingOpeningLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
@@ -1194,13 +1189,13 @@ ruleTester.run("array-bracket-newline", rule, {
             options: [{ multiline: false }],
             errors: [
                 {
-                    message: ERR_NO_BREAK_AFTER,
+                    messageId: "unexpectedOpeningLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
                 },
                 {
-                    message: ERR_NO_BREAK_BEFORE,
+                    messageId: "unexpectedClosingLinebreak",
                     type: "ArrayExpression",
                     line: 2,
                     column: 1
@@ -1213,13 +1208,13 @@ ruleTester.run("array-bracket-newline", rule, {
             options: [{ multiline: false }],
             errors: [
                 {
-                    message: ERR_NO_BREAK_AFTER,
+                    messageId: "unexpectedOpeningLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
                 },
                 {
-                    message: ERR_NO_BREAK_BEFORE,
+                    messageId: "unexpectedClosingLinebreak",
                     type: "ArrayExpression",
                     line: 3,
                     column: 1
@@ -1232,13 +1227,13 @@ ruleTester.run("array-bracket-newline", rule, {
             options: [{ multiline: false }],
             errors: [
                 {
-                    message: ERR_NO_BREAK_AFTER,
+                    messageId: "unexpectedOpeningLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
                 },
                 {
-                    message: ERR_NO_BREAK_BEFORE,
+                    messageId: "unexpectedClosingLinebreak",
                     type: "ArrayExpression",
                     line: 3,
                     column: 1
@@ -1251,13 +1246,13 @@ ruleTester.run("array-bracket-newline", rule, {
             options: [{ multiline: false }],
             errors: [
                 {
-                    message: ERR_NO_BREAK_AFTER,
+                    messageId: "unexpectedOpeningLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
                 },
                 {
-                    message: ERR_NO_BREAK_BEFORE,
+                    messageId: "unexpectedClosingLinebreak",
                     type: "ArrayExpression",
                     line: 4,
                     column: 1
@@ -1270,13 +1265,13 @@ ruleTester.run("array-bracket-newline", rule, {
             options: [{ multiline: false }],
             errors: [
                 {
-                    message: ERR_NO_BREAK_AFTER,
+                    messageId: "unexpectedOpeningLinebreak",
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
                 },
                 {
-                    message: ERR_NO_BREAK_BEFORE,
+                    messageId: "unexpectedClosingLinebreak",
                     type: "ArrayExpression",
                     line: 5,
                     column: 1
@@ -1295,13 +1290,13 @@ ruleTester.run("array-bracket-newline", rule, {
             parserOptions: { ecmaVersion: 6 },
             errors: [
                 {
-                    message: ERR_BREAK_AFTER,
+                    messageId: "missingOpeningLinebreak",
                     type: "ArrayPattern",
                     line: 1,
                     column: 5
                 },
                 {
-                    message: ERR_BREAK_BEFORE,
+                    messageId: "missingClosingLinebreak",
                     type: "ArrayPattern",
                     line: 1,
                     column: 6
@@ -1315,13 +1310,13 @@ ruleTester.run("array-bracket-newline", rule, {
             parserOptions: { ecmaVersion: 6 },
             errors: [
                 {
-                    message: ERR_BREAK_AFTER,
+                    messageId: "missingOpeningLinebreak",
                     type: "ArrayPattern",
                     line: 1,
                     column: 5
                 },
                 {
-                    message: ERR_BREAK_BEFORE,
+                    messageId: "missingClosingLinebreak",
                     type: "ArrayPattern",
                     line: 1,
                     column: 7
@@ -1335,7 +1330,7 @@ ruleTester.run("array-bracket-newline", rule, {
             parserOptions: { ecmaVersion: 6 },
             errors: [
                 {
-                    message: ERR_BREAK_BEFORE,
+                    messageId: "missingClosingLinebreak",
                     type: "ArrayPattern",
                     line: 2,
                     column: 2
@@ -1349,7 +1344,7 @@ ruleTester.run("array-bracket-newline", rule, {
             parserOptions: { ecmaVersion: 6 },
             errors: [
                 {
-                    message: ERR_BREAK_BEFORE,
+                    messageId: "missingClosingLinebreak",
                     type: "ArrayPattern",
                     line: 2,
                     column: 2
@@ -1363,13 +1358,13 @@ ruleTester.run("array-bracket-newline", rule, {
             parserOptions: { ecmaVersion: 6 },
             errors: [
                 {
-                    message: ERR_BREAK_AFTER,
+                    messageId: "missingOpeningLinebreak",
                     type: "ArrayPattern",
                     line: 1,
                     column: 5
                 },
                 {
-                    message: ERR_BREAK_BEFORE,
+                    messageId: "missingClosingLinebreak",
                     type: "ArrayPattern",
                     line: 1,
                     column: 10
@@ -1383,7 +1378,7 @@ ruleTester.run("array-bracket-newline", rule, {
             parserOptions: { ecmaVersion: 6 },
             errors: [
                 {
-                    message: ERR_BREAK_AFTER,
+                    messageId: "missingOpeningLinebreak",
                     type: "ArrayPattern",
                     line: 1,
                     column: 5
@@ -1397,13 +1392,13 @@ ruleTester.run("array-bracket-newline", rule, {
             parserOptions: { ecmaVersion: 6 },
             errors: [
                 {
-                    message: ERR_BREAK_AFTER,
+                    messageId: "missingOpeningLinebreak",
                     type: "ArrayPattern",
                     line: 1,
                     column: 5
                 },
                 {
-                    message: ERR_BREAK_BEFORE,
+                    messageId: "missingClosingLinebreak",
                     type: "ArrayPattern",
                     line: 1,
                     column: 28
@@ -1417,13 +1412,13 @@ ruleTester.run("array-bracket-newline", rule, {
             parserOptions: { ecmaVersion: 6 },
             errors: [
                 {
-                    message: ERR_BREAK_AFTER,
+                    messageId: "missingOpeningLinebreak",
                     type: "ArrayPattern",
                     line: 1,
                     column: 5
                 },
                 {
-                    message: ERR_BREAK_BEFORE,
+                    messageId: "missingClosingLinebreak",
                     type: "ArrayPattern",
                     line: 2,
                     column: 2
@@ -1439,7 +1434,7 @@ ruleTester.run("array-bracket-newline", rule, {
             parserOptions: { ecmaVersion: 6 },
             errors: [
                 {
-                    message: ERR_BREAK_BEFORE,
+                    messageId: "missingClosingLinebreak",
                     type: "ArrayPattern",
                     line: 2,
                     column: 2,
@@ -1455,7 +1450,7 @@ ruleTester.run("array-bracket-newline", rule, {
             parserOptions: { ecmaVersion: 6 },
             errors: [
                 {
-                    message: ERR_NO_BREAK_BEFORE,
+                    messageId: "unexpectedClosingLinebreak",
                     type: "ArrayPattern",
                     line: 2,
                     column: 1,
@@ -1473,13 +1468,13 @@ ruleTester.run("array-bracket-newline", rule, {
             parserOptions: { ecmaVersion: 6 },
             errors: [
                 {
-                    message: ERR_NO_BREAK_AFTER,
+                    messageId: "unexpectedOpeningLinebreak",
                     type: "ArrayPattern",
                     line: 1,
                     column: 5
                 },
                 {
-                    message: ERR_NO_BREAK_BEFORE,
+                    messageId: "unexpectedClosingLinebreak",
                     type: "ArrayPattern",
                     line: 2,
                     column: 1
@@ -1493,13 +1488,13 @@ ruleTester.run("array-bracket-newline", rule, {
             parserOptions: { ecmaVersion: 6 },
             errors: [
                 {
-                    message: ERR_NO_BREAK_AFTER,
+                    messageId: "unexpectedOpeningLinebreak",
                     type: "ArrayPattern",
                     line: 1,
                     column: 5
                 },
                 {
-                    message: ERR_NO_BREAK_BEFORE,
+                    messageId: "unexpectedClosingLinebreak",
                     type: "ArrayPattern",
                     line: 3,
                     column: 1
@@ -1513,13 +1508,13 @@ ruleTester.run("array-bracket-newline", rule, {
             parserOptions: { ecmaVersion: 6 },
             errors: [
                 {
-                    message: ERR_BREAK_AFTER,
+                    messageId: "missingOpeningLinebreak",
                     type: "ArrayPattern",
                     line: 1,
                     column: 5
                 },
                 {
-                    message: ERR_BREAK_BEFORE,
+                    messageId: "missingClosingLinebreak",
                     type: "ArrayPattern",
                     line: 1,
                     column: 10
@@ -1533,13 +1528,13 @@ ruleTester.run("array-bracket-newline", rule, {
             parserOptions: { ecmaVersion: 6 },
             errors: [
                 {
-                    message: ERR_BREAK_AFTER,
+                    messageId: "missingOpeningLinebreak",
                     type: "ArrayPattern",
                     line: 1,
                     column: 5
                 },
                 {
-                    message: ERR_BREAK_BEFORE,
+                    messageId: "missingClosingLinebreak",
                     type: "ArrayPattern",
                     line: 2,
                     column: 2
diff --git a/tests/lib/rules/array-bracket-spacing.js b/tests/lib/rules/array-bracket-spacing.js
index d8406faf38b..da3dadd6ec5 100644
--- a/tests/lib/rules/array-bracket-spacing.js
+++ b/tests/lib/rules/array-bracket-spacing.js
@@ -185,7 +185,10 @@ ruleTester.run("array-bracket-spacing", rule, {
             options: ["never"],
             errors: [
                 {
-                    message: "There should be no space after '['.",
+                    messageId: "unexpectedSpaceAfter",
+                    data: {
+                        tokenValue: "["
+                    },
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
@@ -200,13 +203,19 @@ ruleTester.run("array-bracket-spacing", rule, {
             options: ["always", { objectsInArrays: false }],
             errors: [
                 {
-                    message: "There should be no space after '['.",
+                    messageId: "unexpectedSpaceAfter",
+                    data: {
+                        tokenValue: "["
+                    },
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
                 },
                 {
-                    message: "A space is required before ']'.",
+                    messageId: "missingSpaceBefore",
+                    data: {
+                        tokenValue: "]"
+                    },
                     type: "ArrayExpression",
                     line: 1,
                     column: 36
@@ -219,13 +228,19 @@ ruleTester.run("array-bracket-spacing", rule, {
             options: ["always", { objectsInArrays: false }],
             errors: [
                 {
-                    message: "A space is required after '['.",
+                    messageId: "missingSpaceAfter",
+                    data: {
+                        tokenValue: "["
+                    },
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
                 },
                 {
-                    message: "There should be no space before ']'.",
+                    messageId: "unexpectedSpaceBefore",
+                    data: {
+                        tokenValue: "]"
+                    },
                     type: "ArrayExpression",
                     line: 1,
                     column: 35
@@ -238,13 +253,19 @@ ruleTester.run("array-bracket-spacing", rule, {
             options: ["always", { objectsInArrays: false }],
             errors: [
                 {
-                    message: "There should be no space after '['.",
+                    messageId: "unexpectedSpaceAfter",
+                    data: {
+                        tokenValue: "["
+                    },
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
                 },
                 {
-                    message: "There should be no space before ']'.",
+                    messageId: "unexpectedSpaceBefore",
+                    data: {
+                        tokenValue: "]"
+                    },
                     type: "ArrayExpression",
                     line: 1,
                     column: 50
@@ -259,13 +280,19 @@ ruleTester.run("array-bracket-spacing", rule, {
             options: ["always", { singleValue: false }],
             errors: [
                 {
-                    message: "There should be no space after '['.",
+                    messageId: "unexpectedSpaceAfter",
+                    data: {
+                        tokenValue: "["
+                    },
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
                 },
                 {
-                    message: "There should be no space before ']'.",
+                    messageId: "unexpectedSpaceBefore",
+                    data: {
+                        tokenValue: "]"
+                    },
                     type: "ArrayExpression",
                     line: 1,
                     column: 19
@@ -278,7 +305,10 @@ ruleTester.run("array-bracket-spacing", rule, {
             options: ["always", { singleValue: false }],
             errors: [
                 {
-                    message: "There should be no space before ']'.",
+                    messageId: "unexpectedSpaceBefore",
+                    data: {
+                        tokenValue: "]"
+                    },
                     type: "ArrayExpression",
                     line: 1,
                     column: 18
@@ -291,13 +321,19 @@ ruleTester.run("array-bracket-spacing", rule, {
             options: ["never", { singleValue: true }],
             errors: [
                 {
-                    message: "A space is required after '['.",
+                    messageId: "missingSpaceAfter",
+                    data: {
+                        tokenValue: "["
+                    },
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
                 },
                 {
-                    message: "A space is required before ']'.",
+                    messageId: "missingSpaceBefore",
+                    data: {
+                        tokenValue: "]"
+                    },
                     type: "ArrayExpression",
                     line: 1,
                     column: 17
@@ -312,7 +348,10 @@ ruleTester.run("array-bracket-spacing", rule, {
             options: ["always", { arraysInArrays: false }],
             errors: [
                 {
-                    message: "There should be no space after '['.",
+                    messageId: "unexpectedSpaceAfter",
+                    data: {
+                        tokenValue: "["
+                    },
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
@@ -325,7 +364,10 @@ ruleTester.run("array-bracket-spacing", rule, {
             options: ["always", { arraysInArrays: false }],
             errors: [
                 {
-                    message: "There should be no space before ']'.",
+                    messageId: "unexpectedSpaceBefore",
+                    data: {
+                        tokenValue: "]"
+                    },
                     type: "ArrayExpression",
                     line: 1,
                     column: 31
@@ -338,7 +380,10 @@ ruleTester.run("array-bracket-spacing", rule, {
             options: ["always", { arraysInArrays: false }],
             errors: [
                 {
-                    message: "There should be no space before ']'.",
+                    messageId: "unexpectedSpaceBefore",
+                    data: {
+                        tokenValue: "]"
+                    },
                     type: "ArrayExpression",
                     line: 1,
                     column: 34
@@ -351,7 +396,10 @@ ruleTester.run("array-bracket-spacing", rule, {
             options: ["always", { arraysInArrays: false }],
             errors: [
                 {
-                    message: "There should be no space after '['.",
+                    messageId: "unexpectedSpaceAfter",
+                    data: {
+                        tokenValue: "["
+                    },
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
@@ -364,13 +412,19 @@ ruleTester.run("array-bracket-spacing", rule, {
             options: ["always", { arraysInArrays: false }],
             errors: [
                 {
-                    message: "There should be no space after '['.",
+                    messageId: "unexpectedSpaceAfter",
+                    data: {
+                        tokenValue: "["
+                    },
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
                 },
                 {
-                    message: "There should be no space before ']'.",
+                    messageId: "unexpectedSpaceBefore",
+                    data: {
+                        tokenValue: "]"
+                    },
                     type: "ArrayExpression",
                     line: 1,
                     column: 35
@@ -385,13 +439,19 @@ ruleTester.run("array-bracket-spacing", rule, {
             options: ["always"],
             parserOptions: { ecmaVersion: 6 },
             errors: [{
-                message: "A space is required after '['.",
+                messageId: "missingSpaceAfter",
+                data: {
+                    tokenValue: "["
+                },
                 type: "ArrayPattern",
                 line: 1,
                 column: 5
             },
             {
-                message: "A space is required before ']'.",
+                messageId: "missingSpaceBefore",
+                data: {
+                    tokenValue: "]"
+                },
                 type: "ArrayPattern",
                 line: 1,
                 column: 9
@@ -403,7 +463,10 @@ ruleTester.run("array-bracket-spacing", rule, {
             options: ["always"],
             parserOptions: { ecmaVersion: 6 },
             errors: [{
-                message: "A space is required after '['.",
+                messageId: "missingSpaceAfter",
+                data: {
+                    tokenValue: "["
+                },
                 type: "ArrayPattern",
                 line: 1,
                 column: 5
@@ -415,13 +478,19 @@ ruleTester.run("array-bracket-spacing", rule, {
             options: ["always"],
             parserOptions: { ecmaVersion: 6 },
             errors: [{
-                message: "A space is required after '['.",
+                messageId: "missingSpaceAfter",
+                data: {
+                    tokenValue: "["
+                },
                 type: "ArrayPattern",
                 line: 1,
                 column: 5
             },
             {
-                message: "A space is required before ']'.",
+                messageId: "missingSpaceBefore",
+                data: {
+                    tokenValue: "]"
+                },
                 type: "ArrayPattern",
                 line: 1,
                 column: 12
@@ -433,7 +502,10 @@ ruleTester.run("array-bracket-spacing", rule, {
             options: ["always"],
             parserOptions: { ecmaVersion: 6 },
             errors: [{
-                message: "A space is required before ']'.",
+                messageId: "missingSpaceBefore",
+                data: {
+                    tokenValue: "]"
+                },
                 type: "ArrayPattern",
                 line: 1,
                 column: 13
@@ -445,13 +517,19 @@ ruleTester.run("array-bracket-spacing", rule, {
             options: ["always"],
             parserOptions: { ecmaVersion: 6 },
             errors: [{
-                message: "A space is required after '['.",
+                messageId: "missingSpaceAfter",
+                data: {
+                    tokenValue: "["
+                },
                 type: "ArrayPattern",
                 line: 1,
                 column: 5
             },
             {
-                message: "A space is required before ']'.",
+                messageId: "missingSpaceBefore",
+                data: {
+                    tokenValue: "]"
+                },
                 type: "ArrayPattern",
                 line: 1,
                 column: 14
@@ -463,7 +541,10 @@ ruleTester.run("array-bracket-spacing", rule, {
             options: ["always"],
             parserOptions: { ecmaVersion: 6 },
             errors: [{
-                message: "A space is required after '['.",
+                messageId: "missingSpaceAfter",
+                data: {
+                    tokenValue: "["
+                },
                 type: "ArrayPattern",
                 line: 1,
                 column: 5
@@ -475,7 +556,10 @@ ruleTester.run("array-bracket-spacing", rule, {
             options: ["always", { arraysInArrays: false }],
             parserOptions: { ecmaVersion: 6 },
             errors: [{
-                message: "There should be no space after '['.",
+                messageId: "unexpectedSpaceAfter",
+                data: {
+                    tokenValue: "["
+                },
                 type: "ArrayPattern",
                 line: 1,
                 column: 5
@@ -487,7 +571,10 @@ ruleTester.run("array-bracket-spacing", rule, {
             options: ["always", { objectsInArrays: false }],
             parserOptions: { ecmaVersion: 6 },
             errors: [{
-                message: "There should be no space after '['.",
+                messageId: "unexpectedSpaceAfter",
+                data: {
+                    tokenValue: "["
+                },
                 type: "ArrayPattern",
                 line: 1,
                 column: 1
@@ -499,7 +586,10 @@ ruleTester.run("array-bracket-spacing", rule, {
             options: ["always", { objectsInArrays: false }],
             parserOptions: { ecmaVersion: 6 },
             errors: [{
-                message: "There should be no space before ']'.",
+                messageId: "unexpectedSpaceBefore",
+                data: {
+                    tokenValue: "]"
+                },
                 type: "ArrayPattern",
                 line: 1,
                 column: 15
@@ -513,13 +603,19 @@ ruleTester.run("array-bracket-spacing", rule, {
             options: ["never", { arraysInArrays: true }],
             errors: [
                 {
-                    message: "A space is required after '['.",
+                    messageId: "missingSpaceAfter",
+                    data: {
+                        tokenValue: "["
+                    },
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
                 },
                 {
-                    message: "A space is required before ']'.",
+                    messageId: "missingSpaceBefore",
+                    data: {
+                        tokenValue: "]"
+                    },
                     type: "ArrayExpression",
                     line: 1,
                     column: 29
@@ -532,7 +628,10 @@ ruleTester.run("array-bracket-spacing", rule, {
             options: ["never", { arraysInArrays: true }],
             errors: [
                 {
-                    message: "There should be no space after '['.",
+                    messageId: "unexpectedSpaceAfter",
+                    data: {
+                        tokenValue: "["
+                    },
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
@@ -547,7 +646,10 @@ ruleTester.run("array-bracket-spacing", rule, {
             options: ["never", { objectsInArrays: true }],
             errors: [
                 {
-                    message: "There should be no space after '['.",
+                    messageId: "unexpectedSpaceAfter",
+                    data: {
+                        tokenValue: "["
+                    },
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
@@ -562,13 +664,19 @@ ruleTester.run("array-bracket-spacing", rule, {
             options: ["always"],
             errors: [
                 {
-                    message: "A space is required after '['.",
+                    messageId: "missingSpaceAfter",
+                    data: {
+                        tokenValue: "["
+                    },
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
                 },
                 {
-                    message: "A space is required before ']'.",
+                    messageId: "missingSpaceBefore",
+                    data: {
+                        tokenValue: "]"
+                    },
                     type: "ArrayExpression",
                     line: 1,
                     column: 22
@@ -581,7 +689,10 @@ ruleTester.run("array-bracket-spacing", rule, {
             options: ["always"],
             errors: [
                 {
-                    message: "A space is required after '['.",
+                    messageId: "missingSpaceAfter",
+                    data: {
+                        tokenValue: "["
+                    },
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
@@ -594,7 +705,10 @@ ruleTester.run("array-bracket-spacing", rule, {
             options: ["always"],
             errors: [
                 {
-                    message: "A space is required before ']'.",
+                    messageId: "missingSpaceBefore",
+                    data: {
+                        tokenValue: "]"
+                    },
                     type: "ArrayExpression",
                     line: 1,
                     column: 23
@@ -609,13 +723,19 @@ ruleTester.run("array-bracket-spacing", rule, {
             options: ["never"],
             errors: [
                 {
-                    message: "There should be no space after '['.",
+                    messageId: "unexpectedSpaceAfter",
+                    data: {
+                        tokenValue: "["
+                    },
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
                 },
                 {
-                    message: "There should be no space before ']'.",
+                    messageId: "unexpectedSpaceBefore",
+                    data: {
+                        tokenValue: "]"
+                    },
                     type: "ArrayExpression",
                     line: 1,
                     column: 24
@@ -628,7 +748,10 @@ ruleTester.run("array-bracket-spacing", rule, {
             options: ["never"],
             errors: [
                 {
-                    message: "There should be no space before ']'.",
+                    messageId: "unexpectedSpaceBefore",
+                    data: {
+                        tokenValue: "]"
+                    },
                     type: "ArrayExpression",
                     line: 1,
                     column: 23
@@ -641,7 +764,10 @@ ruleTester.run("array-bracket-spacing", rule, {
             options: ["never"],
             errors: [
                 {
-                    message: "There should be no space after '['.",
+                    messageId: "unexpectedSpaceAfter",
+                    data: {
+                        tokenValue: "["
+                    },
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
@@ -654,13 +780,19 @@ ruleTester.run("array-bracket-spacing", rule, {
             options: ["never"],
             errors: [
                 {
-                    message: "There should be no space after '['.",
+                    messageId: "unexpectedSpaceAfter",
+                    data: {
+                        tokenValue: "["
+                    },
                     type: "ArrayExpression",
                     line: 1,
                     column: 11
                 },
                 {
-                    message: "There should be no space after '['.",
+                    messageId: "unexpectedSpaceAfter",
+                    data: {
+                        tokenValue: "["
+                    },
                     type: "ArrayExpression",
                     line: 1,
                     column: 13
@@ -673,13 +805,19 @@ ruleTester.run("array-bracket-spacing", rule, {
             options: ["never"],
             errors: [
                 {
-                    message: "There should be no space before ']'.",
+                    messageId: "unexpectedSpaceBefore",
+                    data: {
+                        tokenValue: "]"
+                    },
                     type: "ArrayExpression",
                     line: 1,
                     column: 15
                 },
                 {
-                    message: "There should be no space before ']'.",
+                    messageId: "unexpectedSpaceBefore",
+                    data: {
+                        tokenValue: "]"
+                    },
                     type: "ArrayExpression",
                     line: 1,
                     column: 26
@@ -697,13 +835,19 @@ ruleTester.run("array-bracket-spacing", rule, {
             },
             errors: [
                 {
-                    message: "There should be no space after '['.",
+                    messageId: "unexpectedSpaceAfter",
+                    data: {
+                        tokenValue: "["
+                    },
                     type: "ArrayPattern",
                     line: 1,
                     column: 2
                 },
                 {
-                    message: "There should be no space before ']'.",
+                    messageId: "unexpectedSpaceBefore",
+                    data: {
+                        tokenValue: "]"
+                    },
                     type: "ArrayPattern",
                     line: 1,
                     column: 9
@@ -720,13 +864,19 @@ ruleTester.run("array-bracket-spacing", rule, {
             },
             errors: [
                 {
-                    message: "A space is required after '['.",
+                    messageId: "missingSpaceAfter",
+                    data: {
+                        tokenValue: "["
+                    },
                     type: "ArrayPattern",
                     line: 1,
                     column: 2
                 },
                 {
-                    message: "A space is required before ']'.",
+                    messageId: "missingSpaceBefore",
+                    data: {
+                        tokenValue: "]"
+                    },
                     type: "ArrayPattern",
                     line: 1,
                     column: 7
diff --git a/tests/lib/rules/array-callback-return.js b/tests/lib/rules/array-callback-return.js
index 0600bf7830e..47d74fe3994 100644
--- a/tests/lib/rules/array-callback-return.js
+++ b/tests/lib/rules/array-callback-return.js
@@ -82,47 +82,47 @@ ruleTester.run("array-callback-return", rule, {
         { code: "foo.map(function* () {})", parserOptions: { ecmaVersion: 6 } }
     ],
     invalid: [
-        { code: "Array.from(x, function() {})", errors: ["Expected to return a value in function."] },
-        { code: "Array.from(x, function foo() {})", errors: ["Expected to return a value in function 'foo'."] },
-        { code: "Int32Array.from(x, function() {})", errors: ["Expected to return a value in function."] },
-        { code: "Int32Array.from(x, function foo() {})", errors: ["Expected to return a value in function 'foo'."] },
-        { code: "foo.every(function() {})", errors: ["Expected to return a value in function."] },
-        { code: "foo.every(function foo() {})", errors: ["Expected to return a value in function 'foo'."] },
-        { code: "foo.filter(function() {})", errors: ["Expected to return a value in function."] },
-        { code: "foo.filter(function foo() {})", errors: ["Expected to return a value in function 'foo'."] },
-        { code: "foo.find(function() {})", errors: ["Expected to return a value in function."] },
-        { code: "foo.find(function foo() {})", errors: ["Expected to return a value in function 'foo'."] },
-        { code: "foo.findIndex(function() {})", errors: ["Expected to return a value in function."] },
-        { code: "foo.findIndex(function foo() {})", errors: ["Expected to return a value in function 'foo'."] },
-        { code: "foo.map(function() {})", errors: ["Expected to return a value in function."] },
-        { code: "foo.map(function foo() {})", errors: ["Expected to return a value in function 'foo'."] },
-        { code: "foo.reduce(function() {})", errors: ["Expected to return a value in function."] },
-        { code: "foo.reduce(function foo() {})", errors: ["Expected to return a value in function 'foo'."] },
-        { code: "foo.reduceRight(function() {})", errors: ["Expected to return a value in function."] },
-        { code: "foo.reduceRight(function foo() {})", errors: ["Expected to return a value in function 'foo'."] },
-        { code: "foo.some(function() {})", errors: ["Expected to return a value in function."] },
-        { code: "foo.some(function foo() {})", errors: ["Expected to return a value in function 'foo'."] },
-        { code: "foo.sort(function() {})", errors: ["Expected to return a value in function."] },
-        { code: "foo.sort(function foo() {})", errors: ["Expected to return a value in function 'foo'."] },
-        { code: "foo.bar.baz.every(function() {})", errors: ["Expected to return a value in function."] },
-        { code: "foo.bar.baz.every(function foo() {})", errors: ["Expected to return a value in function 'foo'."] },
-        { code: "foo[\"every\"](function() {})", errors: ["Expected to return a value in function."] },
-        { code: "foo[\"every\"](function foo() {})", errors: ["Expected to return a value in function 'foo'."] },
-        { code: "foo[`every`](function() {})", parserOptions: { ecmaVersion: 6 }, errors: ["Expected to return a value in function."] },
-        { code: "foo[`every`](function foo() {})", parserOptions: { ecmaVersion: 6 }, errors: ["Expected to return a value in function 'foo'."] },
+        { code: "Array.from(x, function() {})", errors: [{ messageId: "expectedInside", data: { name: "function" } }] },
+        { code: "Array.from(x, function foo() {})", errors: [{ messageId: "expectedInside", data: { name: "function 'foo'" } }] },
+        { code: "Int32Array.from(x, function() {})", errors: [{ messageId: "expectedInside", data: { name: "function" } }] },
+        { code: "Int32Array.from(x, function foo() {})", errors: [{ messageId: "expectedInside", data: { name: "function 'foo'" } }] },
+        { code: "foo.every(function() {})", errors: [{ messageId: "expectedInside", data: { name: "function" } }] },
+        { code: "foo.every(function foo() {})", errors: [{ messageId: "expectedInside", data: { name: "function 'foo'" } }] },
+        { code: "foo.filter(function() {})", errors: [{ messageId: "expectedInside", data: { name: "function" } }] },
+        { code: "foo.filter(function foo() {})", errors: [{ messageId: "expectedInside", data: { name: "function 'foo'" } }] },
+        { code: "foo.find(function() {})", errors: [{ messageId: "expectedInside", data: { name: "function" } }] },
+        { code: "foo.find(function foo() {})", errors: [{ messageId: "expectedInside", data: { name: "function 'foo'" } }] },
+        { code: "foo.findIndex(function() {})", errors: [{ messageId: "expectedInside", data: { name: "function" } }] },
+        { code: "foo.findIndex(function foo() {})", errors: [{ messageId: "expectedInside", data: { name: "function 'foo'" } }] },
+        { code: "foo.map(function() {})", errors: [{ messageId: "expectedInside", data: { name: "function" } }] },
+        { code: "foo.map(function foo() {})", errors: [{ messageId: "expectedInside", data: { name: "function 'foo'" } }] },
+        { code: "foo.reduce(function() {})", errors: [{ messageId: "expectedInside", data: { name: "function" } }] },
+        { code: "foo.reduce(function foo() {})", errors: [{ messageId: "expectedInside", data: { name: "function 'foo'" } }] },
+        { code: "foo.reduceRight(function() {})", errors: [{ messageId: "expectedInside", data: { name: "function" } }] },
+        { code: "foo.reduceRight(function foo() {})", errors: [{ messageId: "expectedInside", data: { name: "function 'foo'" } }] },
+        { code: "foo.some(function() {})", errors: [{ messageId: "expectedInside", data: { name: "function" } }] },
+        { code: "foo.some(function foo() {})", errors: [{ messageId: "expectedInside", data: { name: "function 'foo'" } }] },
+        { code: "foo.sort(function() {})", errors: [{ messageId: "expectedInside", data: { name: "function" } }] },
+        { code: "foo.sort(function foo() {})", errors: [{ messageId: "expectedInside", data: { name: "function 'foo'" } }] },
+        { code: "foo.bar.baz.every(function() {})", errors: [{ messageId: "expectedInside", data: { name: "function" } }] },
+        { code: "foo.bar.baz.every(function foo() {})", errors: [{ messageId: "expectedInside", data: { name: "function 'foo'" } }] },
+        { code: "foo[\"every\"](function() {})", errors: [{ messageId: "expectedInside", data: { name: "function" } }] },
+        { code: "foo[\"every\"](function foo() {})", errors: [{ messageId: "expectedInside", data: { name: "function 'foo'" } }] },
+        { code: "foo[`every`](function() {})", parserOptions: { ecmaVersion: 6 }, errors: [{ messageId: "expectedInside", data: { name: "function" } }] },
+        { code: "foo[`every`](function foo() {})", parserOptions: { ecmaVersion: 6 }, errors: [{ messageId: "expectedInside", data: { name: "function 'foo'" } }] },
         { code: "foo.every(() => {})", parserOptions: { ecmaVersion: 6 }, errors: [{ message: "Expected to return a value in arrow function.", column: 14 }] },
         { code: "foo.every(function() { if (a) return true; })", errors: [{ message: "Expected to return a value at the end of function.", column: 11 }] },
         { code: "foo.every(function cb() { if (a) return true; })", errors: [{ message: "Expected to return a value at the end of function 'cb'.", column: 20 }] },
-        { code: "foo.every(function() { switch (a) { case 0: break; default: return true; } })", errors: ["Expected to return a value at the end of function."] },
-        { code: "foo.every(function foo() { switch (a) { case 0: break; default: return true; } })", errors: ["Expected to return a value at the end of function 'foo'."] },
-        { code: "foo.every(function() { try { bar(); } catch (err) { return true; } })", errors: ["Expected to return a value at the end of function."] },
-        { code: "foo.every(function foo() { try { bar(); } catch (err) { return true; } })", errors: ["Expected to return a value at the end of function 'foo'."] },
-        { code: "foo.every(function() { return; })", errors: ["Function expected a return value."] },
-        { code: "foo.every(function foo() { return; })", errors: ["Function 'foo' expected a return value."] },
-        { code: "foo.every(function() { if (a) return; })", errors: ["Expected to return a value at the end of function.", "Function expected a return value."] },
-        { code: "foo.every(function foo() { if (a) return; })", errors: ["Expected to return a value at the end of function 'foo'.", "Function 'foo' expected a return value."] },
-        { code: "foo.every(function() { if (a) return; else return; })", errors: ["Function expected a return value.", "Function expected a return value."] },
-        { code: "foo.every(function foo() { if (a) return; else return; })", errors: ["Function 'foo' expected a return value.", "Function 'foo' expected a return value."] },
+        { code: "foo.every(function() { switch (a) { case 0: break; default: return true; } })", errors: [{ messageId: "expectedAtEnd", data: { name: "function" } }] },
+        { code: "foo.every(function foo() { switch (a) { case 0: break; default: return true; } })", errors: [{ messageId: "expectedAtEnd", data: { name: "function 'foo'" } }] },
+        { code: "foo.every(function() { try { bar(); } catch (err) { return true; } })", errors: [{ messageId: "expectedAtEnd", data: { name: "function" } }] },
+        { code: "foo.every(function foo() { try { bar(); } catch (err) { return true; } })", errors: [{ messageId: "expectedAtEnd", data: { name: "function 'foo'" } }] },
+        { code: "foo.every(function() { return; })", errors: [{ messageId: "expectedReturnValue", data: { name: "Function" } }] },
+        { code: "foo.every(function foo() { return; })", errors: [{ messageId: "expectedReturnValue", data: { name: "Function 'foo'" } }] },
+        { code: "foo.every(function() { if (a) return; })", errors: ["Expected to return a value at the end of function.", { messageId: "expectedReturnValue", data: { name: "Function" } }] },
+        { code: "foo.every(function foo() { if (a) return; })", errors: ["Expected to return a value at the end of function 'foo'.", { messageId: "expectedReturnValue", data: { name: "Function 'foo'" } }] },
+        { code: "foo.every(function() { if (a) return; else return; })", errors: [{ messageId: "expectedReturnValue", data: { name: "Function" } }, { messageId: "expectedReturnValue", data: { name: "Function" } }] },
+        { code: "foo.every(function foo() { if (a) return; else return; })", errors: [{ messageId: "expectedReturnValue", data: { name: "Function 'foo'" } }, { messageId: "expectedReturnValue", data: { name: "Function 'foo'" } }] },
         { code: "foo.every(cb || function() {})", errors: ["Expected to return a value in function."] },
         { code: "foo.every(cb || function foo() {})", errors: ["Expected to return a value in function 'foo'."] },
         { code: "foo.every(a ? function() {} : function() {})", errors: ["Expected to return a value in function.", "Expected to return a value in function."] },
diff --git a/tests/lib/rules/array-element-newline.js b/tests/lib/rules/array-element-newline.js
index c918c0ce053..f652105fc24 100644
--- a/tests/lib/rules/array-element-newline.js
+++ b/tests/lib/rules/array-element-newline.js
@@ -19,9 +19,6 @@ const RuleTester = require("../../../lib/testers/rule-tester");
 
 const ruleTester = new RuleTester();
 
-const ERR_NO_BREAK_HERE = "There should be no linebreak here.";
-const ERR_BREAK_HERE = "There should be a linebreak after this element.";
-
 ruleTester.run("array-element-newline", rule, {
 
     valid: [
@@ -137,7 +134,7 @@ ruleTester.run("array-element-newline", rule, {
             options: ["always"],
             errors: [
                 {
-                    message: ERR_BREAK_HERE,
+                    messageId: "missingLineBreak",
                     line: 1,
                     column: 14,
                     endLine: 1,
@@ -151,14 +148,14 @@ ruleTester.run("array-element-newline", rule, {
             options: ["always"],
             errors: [
                 {
-                    message: ERR_BREAK_HERE,
+                    messageId: "missingLineBreak",
                     line: 1,
                     column: 14,
                     endLine: 1,
                     endColumn: 15
                 },
                 {
-                    message: ERR_BREAK_HERE,
+                    messageId: "missingLineBreak",
                     line: 1,
                     column: 17,
                     endLine: 1,
@@ -172,14 +169,14 @@ ruleTester.run("array-element-newline", rule, {
             options: ["always"],
             errors: [
                 {
-                    message: ERR_BREAK_HERE,
+                    messageId: "missingLineBreak",
                     line: 1,
                     column: 14,
                     endLine: 1,
                     endColumn: 14
                 },
                 {
-                    message: ERR_BREAK_HERE,
+                    messageId: "missingLineBreak",
                     line: 1,
                     column: 16,
                     endLine: 1,
@@ -193,14 +190,14 @@ ruleTester.run("array-element-newline", rule, {
             options: ["always"],
             errors: [
                 {
-                    message: ERR_BREAK_HERE,
+                    messageId: "missingLineBreak",
                     line: 1,
                     column: 14,
                     endLine: 1,
                     endColumn: 15
                 },
                 {
-                    message: ERR_BREAK_HERE,
+                    messageId: "missingLineBreak",
                     line: 1,
                     column: 19,
                     endLine: 1,
@@ -214,12 +211,12 @@ ruleTester.run("array-element-newline", rule, {
             options: ["always"],
             errors: [
                 {
-                    message: ERR_BREAK_HERE,
+                    messageId: "missingLineBreak",
                     line: 1,
                     column: 14
                 },
                 {
-                    message: ERR_BREAK_HERE,
+                    messageId: "missingLineBreak",
                     line: 3,
                     column: 3
                 }
@@ -231,7 +228,7 @@ ruleTester.run("array-element-newline", rule, {
             options: ["always"],
             errors: [
                 {
-                    message: ERR_BREAK_HERE,
+                    messageId: "missingLineBreak",
                     line: 1,
                     column: 14
                 }
@@ -243,14 +240,14 @@ ruleTester.run("array-element-newline", rule, {
             options: ["always"],
             errors: [
                 {
-                    message: ERR_BREAK_HERE,
+                    messageId: "missingLineBreak",
                     line: 1,
                     column: 14,
                     endLine: 1,
                     endColumn: 15
                 },
                 {
-                    message: ERR_BREAK_HERE,
+                    messageId: "missingLineBreak",
                     line: 1,
                     column: 25,
                     endLine: 1,
@@ -264,14 +261,14 @@ ruleTester.run("array-element-newline", rule, {
             options: ["always"],
             errors: [
                 {
-                    message: ERR_BREAK_HERE,
+                    messageId: "missingLineBreak",
                     line: 1,
                     column: 31,
                     endLine: 1,
                     endColumn: 31
                 },
                 {
-                    message: ERR_BREAK_HERE,
+                    messageId: "missingLineBreak",
                     line: 1,
                     column: 35,
                     endLine: 1,
@@ -285,14 +282,14 @@ ruleTester.run("array-element-newline", rule, {
             options: ["always"],
             errors: [
                 {
-                    message: ERR_BREAK_HERE,
+                    messageId: "missingLineBreak",
                     line: 1,
                     column: 14,
                     endLine: 1,
                     endColumn: 14
                 },
                 {
-                    message: ERR_BREAK_HERE,
+                    messageId: "missingLineBreak",
                     line: 1,
                     column: 20,
                     endLine: 1,
@@ -306,14 +303,14 @@ ruleTester.run("array-element-newline", rule, {
             options: ["always"],
             errors: [
                 {
-                    message: ERR_BREAK_HERE,
+                    messageId: "missingLineBreak",
                     line: 1,
                     column: 14,
                     endLine: 1,
                     endColumn: 15
                 },
                 {
-                    message: ERR_BREAK_HERE,
+                    messageId: "missingLineBreak",
                     line: 1,
                     column: 19,
                     endLine: 1,
@@ -327,7 +324,7 @@ ruleTester.run("array-element-newline", rule, {
             options: ["always"],
             errors: [
                 {
-                    message: ERR_BREAK_HERE,
+                    messageId: "missingLineBreak",
                     line: 4,
                     column: 3
                 }
@@ -339,7 +336,7 @@ ruleTester.run("array-element-newline", rule, {
             options: ["always"],
             errors: [
                 {
-                    message: ERR_BREAK_HERE,
+                    messageId: "missingLineBreak",
                     line: 4,
                     column: 4
                 }
@@ -353,7 +350,7 @@ ruleTester.run("array-element-newline", rule, {
             options: ["never"],
             errors: [
                 {
-                    message: ERR_NO_BREAK_HERE,
+                    messageId: "unexpectedLineBreak",
                     line: 2,
                     column: 3
                 }
@@ -365,7 +362,7 @@ ruleTester.run("array-element-newline", rule, {
             options: ["never"],
             errors: [
                 {
-                    message: ERR_NO_BREAK_HERE,
+                    messageId: "unexpectedLineBreak",
                     line: 3,
                     column: 2
                 }
@@ -377,7 +374,7 @@ ruleTester.run("array-element-newline", rule, {
             options: ["never"],
             errors: [
                 {
-                    message: ERR_NO_BREAK_HERE,
+                    messageId: "unexpectedLineBreak",
                     line: 3,
                     column: 2
                 }
@@ -389,7 +386,7 @@ ruleTester.run("array-element-newline", rule, {
             options: ["never"],
             errors: [
                 {
-                    message: ERR_NO_BREAK_HERE,
+                    messageId: "unexpectedLineBreak",
                     line: 2,
                     column: 18
                 }
@@ -401,7 +398,7 @@ ruleTester.run("array-element-newline", rule, {
             options: ["never"],
             errors: [
                 {
-                    message: ERR_NO_BREAK_HERE,
+                    messageId: "unexpectedLineBreak",
                     line: 2,
                     column: 3
                 }
@@ -413,14 +410,14 @@ ruleTester.run("array-element-newline", rule, {
             options: ["never"],
             errors: [
                 {
-                    message: ERR_NO_BREAK_HERE,
+                    messageId: "unexpectedLineBreak",
                     line: 2,
                     column: 3,
                     endLine: 3,
                     endColumn: 1
                 },
                 {
-                    message: ERR_NO_BREAK_HERE,
+                    messageId: "unexpectedLineBreak",
                     line: 3,
                     column: 3,
                     endLine: 4,
@@ -434,7 +431,7 @@ ruleTester.run("array-element-newline", rule, {
             options: ["never"],
             errors: [
                 {
-                    message: ERR_NO_BREAK_HERE,
+                    messageId: "unexpectedLineBreak",
                     line: 4,
                     column: 3
                 }
@@ -446,7 +443,7 @@ ruleTester.run("array-element-newline", rule, {
             options: ["never"],
             errors: [
                 {
-                    message: ERR_NO_BREAK_HERE,
+                    messageId: "unexpectedLineBreak",
                     line: 4,
                     column: 21
                 }
@@ -460,7 +457,7 @@ ruleTester.run("array-element-newline", rule, {
             options: [{ multiline: true }],
             errors: [
                 {
-                    message: ERR_NO_BREAK_HERE,
+                    messageId: "unexpectedLineBreak",
                     line: 1,
                     column: 14
                 }
@@ -472,7 +469,7 @@ ruleTester.run("array-element-newline", rule, {
             options: [{ multiline: true }],
             errors: [
                 {
-                    message: ERR_BREAK_HERE,
+                    messageId: "missingLineBreak",
                     line: 4,
                     column: 3
                 }
@@ -484,7 +481,7 @@ ruleTester.run("array-element-newline", rule, {
             options: [{ multiline: true }],
             errors: [
                 {
-                    message: ERR_BREAK_HERE,
+                    messageId: "missingLineBreak",
                     line: 4,
                     column: 21
                 }
@@ -498,7 +495,7 @@ ruleTester.run("array-element-newline", rule, {
             options: [{ minItems: null }],
             errors: [
                 {
-                    message: ERR_NO_BREAK_HERE,
+                    messageId: "unexpectedLineBreak",
                     line: 1,
                     column: 14
                 }
@@ -510,12 +507,12 @@ ruleTester.run("array-element-newline", rule, {
             options: [{ minItems: null }],
             errors: [
                 {
-                    message: ERR_NO_BREAK_HERE,
+                    messageId: "unexpectedLineBreak",
                     line: 1,
                     column: 14
                 },
                 {
-                    message: ERR_NO_BREAK_HERE,
+                    messageId: "unexpectedLineBreak",
                     line: 2,
                     column: 3
                 }
@@ -527,7 +524,7 @@ ruleTester.run("array-element-newline", rule, {
             options: [{ minItems: null }],
             errors: [
                 {
-                    message: ERR_NO_BREAK_HERE,
+                    messageId: "unexpectedLineBreak",
                     line: 4,
                     column: 3
                 }
@@ -541,7 +538,7 @@ ruleTester.run("array-element-newline", rule, {
             options: [{ minItems: 0 }],
             errors: [
                 {
-                    message: ERR_BREAK_HERE,
+                    messageId: "missingLineBreak",
                     line: 1,
                     column: 14
                 }
@@ -553,12 +550,12 @@ ruleTester.run("array-element-newline", rule, {
             options: [{ minItems: 0 }],
             errors: [
                 {
-                    message: ERR_BREAK_HERE,
+                    messageId: "missingLineBreak",
                     line: 1,
                     column: 14
                 },
                 {
-                    message: ERR_BREAK_HERE,
+                    messageId: "missingLineBreak",
                     line: 1,
                     column: 17
                 }
@@ -570,7 +567,7 @@ ruleTester.run("array-element-newline", rule, {
             options: [{ minItems: 0 }],
             errors: [
                 {
-                    message: ERR_BREAK_HERE,
+                    messageId: "missingLineBreak",
                     line: 4,
                     column: 3
                 }
@@ -584,7 +581,7 @@ ruleTester.run("array-element-newline", rule, {
             options: [{ minItems: 3 }],
             errors: [
                 {
-                    message: ERR_NO_BREAK_HERE,
+                    messageId: "unexpectedLineBreak",
                     line: 1,
                     column: 14
                 }
@@ -596,12 +593,12 @@ ruleTester.run("array-element-newline", rule, {
             options: [{ minItems: 3 }],
             errors: [
                 {
-                    message: ERR_BREAK_HERE,
+                    messageId: "missingLineBreak",
                     line: 1,
                     column: 14
                 },
                 {
-                    message: ERR_BREAK_HERE,
+                    messageId: "missingLineBreak",
                     line: 1,
                     column: 17
                 }
@@ -613,7 +610,7 @@ ruleTester.run("array-element-newline", rule, {
             options: [{ minItems: 3 }],
             errors: [
                 {
-                    message: ERR_NO_BREAK_HERE,
+                    messageId: "unexpectedLineBreak",
                     line: 4,
                     column: 3
                 }
@@ -627,12 +624,12 @@ ruleTester.run("array-element-newline", rule, {
             options: [{ multiline: true, minItems: 3 }],
             errors: [
                 {
-                    message: ERR_BREAK_HERE,
+                    messageId: "missingLineBreak",
                     line: 1,
                     column: 14
                 },
                 {
-                    message: ERR_BREAK_HERE,
+                    messageId: "missingLineBreak",
                     line: 1,
                     column: 17
                 }
@@ -644,7 +641,7 @@ ruleTester.run("array-element-newline", rule, {
             options: [{ multiline: true, minItems: 3 }],
             errors: [
                 {
-                    message: ERR_NO_BREAK_HERE,
+                    messageId: "unexpectedLineBreak",
                     line: 1,
                     column: 14
                 }
@@ -656,7 +653,7 @@ ruleTester.run("array-element-newline", rule, {
             options: [{ multiline: true, minItems: 3 }],
             errors: [
                 {
-                    message: ERR_BREAK_HERE,
+                    messageId: "missingLineBreak",
                     line: 4,
                     column: 3
                 }
@@ -674,7 +671,7 @@ ruleTester.run("array-element-newline", rule, {
             parserOptions: { ecmaVersion: 6 },
             errors: [
                 {
-                    message: ERR_BREAK_HERE,
+                    messageId: "missingLineBreak",
                     line: 1,
                     column: 8
                 }
@@ -687,12 +684,12 @@ ruleTester.run("array-element-newline", rule, {
             parserOptions: { ecmaVersion: 6 },
             errors: [
                 {
-                    message: ERR_BREAK_HERE,
+                    messageId: "missingLineBreak",
                     line: 1,
                     column: 8
                 },
                 {
-                    message: ERR_BREAK_HERE,
+                    messageId: "missingLineBreak",
                     line: 1,
                     column: 11
                 }
@@ -707,7 +704,7 @@ ruleTester.run("array-element-newline", rule, {
             parserOptions: { ecmaVersion: 6 },
             errors: [
                 {
-                    message: ERR_NO_BREAK_HERE,
+                    messageId: "unexpectedLineBreak",
                     line: 1,
                     column: 8
                 }
@@ -720,12 +717,12 @@ ruleTester.run("array-element-newline", rule, {
             parserOptions: { ecmaVersion: 6 },
             errors: [
                 {
-                    message: ERR_BREAK_HERE,
+                    messageId: "missingLineBreak",
                     line: 1,
                     column: 8
                 },
                 {
-                    message: ERR_BREAK_HERE,
+                    messageId: "missingLineBreak",
                     line: 1,
                     column: 11
                 }
diff --git a/tests/lib/rules/arrow-body-style.js b/tests/lib/rules/arrow-body-style.js
index b1b341093f3..14572e98a9c 100644
--- a/tests/lib/rules/arrow-body-style.js
+++ b/tests/lib/rules/arrow-body-style.js
@@ -54,7 +54,7 @@ ruleTester.run("arrow-body-style", rule, {
                     line: 1,
                     column: 17,
                     type: "ArrowFunctionExpression",
-                    message: "Expected block statement surrounding arrow body."
+                    messageId: "expectedBlock"
                 }
             ]
         },
@@ -67,7 +67,7 @@ ruleTester.run("arrow-body-style", rule, {
                     line: 1,
                     column: 18,
                     type: "ArrowFunctionExpression",
-                    message: "Expected block statement surrounding arrow body."
+                    messageId: "expectedBlock"
                 }
             ]
         },
@@ -80,7 +80,7 @@ ruleTester.run("arrow-body-style", rule, {
                     line: 1,
                     column: 17,
                     type: "ArrowFunctionExpression",
-                    message: "Unexpected block statement surrounding arrow body; move the returned value immediately after the `=>`."
+                    messageId: "unexpectedSingleBlock"
                 }
             ]
         },
@@ -93,7 +93,7 @@ ruleTester.run("arrow-body-style", rule, {
                     line: 1,
                     column: 17,
                     type: "ArrowFunctionExpression",
-                    message: "Unexpected block statement surrounding arrow body; move the returned value immediately after the `=>`."
+                    messageId: "unexpectedSingleBlock"
                 }
             ]
         },
@@ -106,7 +106,7 @@ ruleTester.run("arrow-body-style", rule, {
                     line: 1,
                     column: 17,
                     type: "ArrowFunctionExpression",
-                    message: "Unexpected block statement surrounding arrow body; move the returned value immediately after the `=>`."
+                    messageId: "unexpectedSingleBlock"
                 }
             ]
         },
@@ -119,7 +119,7 @@ ruleTester.run("arrow-body-style", rule, {
                     line: 1,
                     column: 17,
                     type: "ArrowFunctionExpression",
-                    message: "Unexpected block statement surrounding arrow body; put a value of `undefined` immediately after the `=>`."
+                    messageId: "unexpectedEmptyBlock"
                 }
             ]
         },
@@ -132,7 +132,7 @@ ruleTester.run("arrow-body-style", rule, {
                     line: 1,
                     column: 17,
                     type: "ArrowFunctionExpression",
-                    message: "Unexpected block statement surrounding arrow body; move the returned value immediately after the `=>`."
+                    messageId: "unexpectedSingleBlock"
                 }
             ]
         },
@@ -145,7 +145,7 @@ ruleTester.run("arrow-body-style", rule, {
                     line: 1,
                     column: 17,
                     type: "ArrowFunctionExpression",
-                    message: "Unexpected block statement surrounding arrow body; parenthesize the returned value and move it immediately after the `=>`."
+                    messageId: "unexpectedObjectBlock"
                 }
             ]
         },
@@ -158,7 +158,7 @@ ruleTester.run("arrow-body-style", rule, {
                     line: 1,
                     column: 17,
                     type: "ArrowFunctionExpression",
-                    message: "Unexpected block statement surrounding arrow body; move the returned value immediately after the `=>`."
+                    messageId: "unexpectedSingleBlock"
                 }
             ]
         },
@@ -171,7 +171,7 @@ ruleTester.run("arrow-body-style", rule, {
                     line: 1,
                     column: 17,
                     type: "ArrowFunctionExpression",
-                    message: "Unexpected block statement surrounding arrow body; move the returned value immediately after the `=>`."
+                    messageId: "unexpectedSingleBlock"
                 }
             ]
         },
@@ -184,7 +184,7 @@ ruleTester.run("arrow-body-style", rule, {
                     line: 1,
                     column: 17,
                     type: "ArrowFunctionExpression",
-                    message: "Unexpected block statement surrounding arrow body; move the returned value immediately after the `=>`."
+                    messageId: "unexpectedSingleBlock"
                 }
             ]
         },
@@ -197,7 +197,7 @@ ruleTester.run("arrow-body-style", rule, {
                     line: 1,
                     column: 17,
                     type: "ArrowFunctionExpression",
-                    message: "Unexpected block statement surrounding arrow body; move the returned value immediately after the `=>`."
+                    messageId: "unexpectedSingleBlock"
                 }
             ]
         },
@@ -210,7 +210,7 @@ ruleTester.run("arrow-body-style", rule, {
                     line: 1,
                     column: 17,
                     type: "ArrowFunctionExpression",
-                    message: "Unexpected block statement surrounding arrow body; parenthesize the returned value and move it immediately after the `=>`."
+                    messageId: "unexpectedObjectBlock"
                 }
             ]
         },
@@ -219,7 +219,7 @@ ruleTester.run("arrow-body-style", rule, {
             output: null, // not fixed
             options: ["never"],
             errors: [
-                { line: 1, column: 27, type: "ArrowFunctionExpression", message: "Unexpected block statement surrounding arrow body." }
+                { line: 1, column: 27, type: "ArrowFunctionExpression", messageId: "unexpectedOtherBlock" }
             ]
         },
         {
@@ -231,7 +231,7 @@ ruleTester.run("arrow-body-style", rule, {
                     line: 1,
                     column: 17,
                     type: "ArrowFunctionExpression",
-                    message: "Unexpected block statement surrounding arrow body; move the returned value immediately after the `=>`."
+                    messageId: "unexpectedSingleBlock"
                 }
             ]
         },
@@ -244,7 +244,7 @@ ruleTester.run("arrow-body-style", rule, {
                     line: 1,
                     column: 17,
                     type: "ArrowFunctionExpression",
-                    message: "Unexpected block statement surrounding arrow body; move the returned value immediately after the `=>`."
+                    messageId: "unexpectedSingleBlock"
                 }
             ]
         },
@@ -257,7 +257,7 @@ ruleTester.run("arrow-body-style", rule, {
                     line: 1,
                     column: 18,
                     type: "ArrowFunctionExpression",
-                    message: "Expected block statement surrounding arrow body."
+                    messageId: "expectedBlock"
                 }
             ]
         },
@@ -270,7 +270,7 @@ ruleTester.run("arrow-body-style", rule, {
                     line: 1,
                     column: 18,
                     type: "ArrowFunctionExpression",
-                    message: "Expected block statement surrounding arrow body."
+                    messageId: "expectedBlock"
                 }
             ]
         },
@@ -283,7 +283,7 @@ ruleTester.run("arrow-body-style", rule, {
                     line: 1,
                     column: 24,
                     type: "ArrowFunctionExpression",
-                    message: "Expected block statement surrounding arrow body."
+                    messageId: "expectedBlock"
                 }
             ]
         },
@@ -296,7 +296,7 @@ ruleTester.run("arrow-body-style", rule, {
             output: null,
             options: ["never"],
             errors: [
-                { line: 1, column: 17, type: "ArrowFunctionExpression", message: "Unexpected block statement surrounding arrow body; move the returned value immediately after the `=>`." }
+                { line: 1, column: 17, type: "ArrowFunctionExpression", messageId: "unexpectedSingleBlock" }
             ]
         },
         {
@@ -308,7 +308,7 @@ ruleTester.run("arrow-body-style", rule, {
             output: null,
             options: ["never"],
             errors: [
-                { line: 1, column: 17, type: "ArrowFunctionExpression", message: "Unexpected block statement surrounding arrow body; move the returned value immediately after the `=>`." }
+                { line: 1, column: 17, type: "ArrowFunctionExpression", messageId: "unexpectedSingleBlock" }
             ]
         },
         {
@@ -326,7 +326,7 @@ ruleTester.run("arrow-body-style", rule, {
                     line: 1,
                     column: 17,
                     type: "ArrowFunctionExpression",
-                    message: "Unexpected block statement surrounding arrow body; move the returned value immediately after the `=>`."
+                    messageId: "unexpectedSingleBlock"
                 }
             ]
         },
@@ -339,7 +339,7 @@ ruleTester.run("arrow-body-style", rule, {
                     line: 1,
                     column: 50,
                     type: "ArrowFunctionExpression",
-                    message: "Unexpected block statement surrounding arrow body; move the returned value immediately after the `=>`."
+                    messageId: "unexpectedSingleBlock"
                 }
             ]
         },
@@ -352,7 +352,7 @@ ruleTester.run("arrow-body-style", rule, {
                     line: 1,
                     column: 60,
                     type: "ArrowFunctionExpression",
-                    message: "Expected block statement surrounding arrow body."
+                    messageId: "expectedBlock"
                 }
             ]
         },
@@ -364,7 +364,7 @@ ruleTester.run("arrow-body-style", rule, {
                     line: 1,
                     column: 17,
                     type: "ArrowFunctionExpression",
-                    message: "Unexpected block statement surrounding arrow body; move the returned value immediately after the `=>`."
+                    messageId: "unexpectedSingleBlock"
                 }
             ]
         },
@@ -376,7 +376,7 @@ ruleTester.run("arrow-body-style", rule, {
                     line: 1,
                     column: 17,
                     type: "ArrowFunctionExpression",
-                    message: "Unexpected block statement surrounding arrow body; move the returned value immediately after the `=>`."
+                    messageId: "unexpectedSingleBlock"
                 }
             ]
         },
@@ -388,7 +388,7 @@ ruleTester.run("arrow-body-style", rule, {
                     line: 1,
                     column: 17,
                     type: "ArrowFunctionExpression",
-                    message: "Unexpected block statement surrounding arrow body; move the returned value immediately after the `=>`."
+                    messageId: "unexpectedSingleBlock"
                 }
             ]
         },
@@ -408,7 +408,7 @@ ruleTester.run("arrow-body-style", rule, {
                     line: 2,
                     column: 31,
                     type: "ArrowFunctionExpression",
-                    message: "Unexpected block statement surrounding arrow body; move the returned value immediately after the `=>`."
+                    messageId: "unexpectedSingleBlock"
                 }
             ]
         },
@@ -432,7 +432,7 @@ ruleTester.run("arrow-body-style", rule, {
                     line: 2,
                     column: 31,
                     type: "ArrowFunctionExpression",
-                    message: "Unexpected block statement surrounding arrow body; parenthesize the returned value and move it immediately after the `=>`."
+                    messageId: "unexpectedObjectBlock"
                 }
             ]
         },
@@ -440,13 +440,13 @@ ruleTester.run("arrow-body-style", rule, {
             code: "var foo = () => ({foo: 1}).foo();",
             output: "var foo = () => {return {foo: 1}.foo()};",
             options: ["always"],
-            errors: ["Expected block statement surrounding arrow body."]
+            errors: [{ messageId: "expectedBlock" }]
         },
         {
             code: "var foo = () => ({foo: 1}.foo());",
             output: "var foo = () => {return {foo: 1}.foo()};",
             options: ["always"],
-            errors: ["Expected block statement surrounding arrow body."]
+            errors: [{ messageId: "expectedBlock" }]
         }
     ]
 });
diff --git a/tests/lib/rules/arrow-parens.js b/tests/lib/rules/arrow-parens.js
index 3fcd6fda606..8062d7313c1 100644
--- a/tests/lib/rules/arrow-parens.js
+++ b/tests/lib/rules/arrow-parens.js
@@ -71,10 +71,6 @@ const valid = [
     { code: "(a): T => a", options: ["as-needed", { requireForBlockBody: true }], parser: parser("return-type") }
 ];
 
-const message = "Expected parentheses around arrow function argument.";
-const asNeededMessage = "Unexpected parentheses around single function argument.";
-const requireForBlockBodyMessage = "Unexpected parentheses around single function argument having a body with no curly braces";
-const requireForBlockBodyNoParensMessage = "Expected parentheses around arrow function argument having a body with curly braces.";
 const type = "ArrowFunctionExpression";
 
 const invalid = [
@@ -86,7 +82,7 @@ const invalid = [
         errors: [{
             line: 1,
             column: 1,
-            message,
+            messageId: "expectedParens",
             type
         }]
     },
@@ -96,7 +92,7 @@ const invalid = [
         errors: [{
             line: 1,
             column: 1,
-            message,
+            messageId: "expectedParens",
             type
         }]
     },
@@ -106,7 +102,7 @@ const invalid = [
         errors: [{
             line: 1,
             column: 1,
-            message,
+            messageId: "expectedParens",
             type
         }]
     },
@@ -116,7 +112,7 @@ const invalid = [
         errors: [{
             line: 1,
             column: 8,
-            message,
+            messageId: "expectedParens",
             type
         }]
     },
@@ -126,7 +122,7 @@ const invalid = [
         errors: [{
             line: 1,
             column: 8,
-            message,
+            messageId: "expectedParens",
             type
         }]
     },
@@ -136,7 +132,7 @@ const invalid = [
         errors: [{
             line: 1,
             column: 3,
-            message,
+            messageId: "expectedParens",
             type
         }]
     },
@@ -147,7 +143,7 @@ const invalid = [
         errors: [{
             line: 1,
             column: 3,
-            message,
+            messageId: "expectedParens",
             type
         }]
     },
@@ -160,7 +156,7 @@ const invalid = [
         errors: [{
             line: 1,
             column: 1,
-            message: asNeededMessage,
+            messageId: "unexpectedParens",
             type
         }]
     },
@@ -172,7 +168,7 @@ const invalid = [
         errors: [{
             line: 1,
             column: 1,
-            message: asNeededMessage,
+            messageId: "unexpectedParens",
             type
         }]
     },
@@ -184,7 +180,7 @@ const invalid = [
         errors: [{
             line: 1,
             column: 1,
-            message: asNeededMessage,
+            messageId: "unexpectedParens",
             type
         }]
     },
@@ -196,7 +192,7 @@ const invalid = [
         errors: [{
             line: 1,
             column: 1,
-            message: asNeededMessage,
+            messageId: "unexpectedParens",
             type
         }]
     },
@@ -209,7 +205,7 @@ const invalid = [
         errors: [{
             line: 1,
             column: 1,
-            message: requireForBlockBodyNoParensMessage,
+            messageId: "expectedParensBlock",
             type
         }]
     },
@@ -220,7 +216,7 @@ const invalid = [
         errors: [{
             line: 1,
             column: 1,
-            message: requireForBlockBodyMessage,
+            messageId: "unexpectedParensInline",
             type
         }]
     },
@@ -232,7 +228,7 @@ const invalid = [
         errors: [{
             line: 1,
             column: 1,
-            message: requireForBlockBodyNoParensMessage,
+            messageId: "expectedParensBlock",
             type
         }]
     },
@@ -244,7 +240,7 @@ const invalid = [
         errors: [{
             line: 1,
             column: 1,
-            message: requireForBlockBodyMessage,
+            messageId: "unexpectedParensInline",
             type
         }]
     },
@@ -256,7 +252,7 @@ const invalid = [
         errors: [{
             line: 1,
             column: 1,
-            message: requireForBlockBodyMessage,
+            messageId: "unexpectedParensInline",
             type
         }]
     }
diff --git a/tests/lib/rules/arrow-spacing.js b/tests/lib/rules/arrow-spacing.js
index 53c6dcd5ea9..643fc70495a 100644
--- a/tests/lib/rules/arrow-spacing.js
+++ b/tests/lib/rules/arrow-spacing.js
@@ -91,8 +91,8 @@ const invalid = [
         output: "a => a",
         options: [{ after: true, before: true }],
         errors: [
-            { column: 1, line: 1, type: "Identifier" },
-            { column: 4, line: 1, type: "Identifier" }
+            { column: 1, line: 1, type: "Identifier", messageId: "expectedBefore" },
+            { column: 4, line: 1, type: "Identifier", messageId: "expectedAfter" }
         ]
     },
     {
@@ -100,8 +100,8 @@ const invalid = [
         output: "() => {}",
         options: [{ after: true, before: true }],
         errors: [
-            { column: 2, line: 1, type: "Punctuator" },
-            { column: 5, line: 1, type: "Punctuator" }
+            { column: 2, line: 1, type: "Punctuator", messageId: "expectedBefore" },
+            { column: 5, line: 1, type: "Punctuator", messageId: "expectedAfter" }
         ]
     },
     {
@@ -109,8 +109,8 @@ const invalid = [
         output: "(a) => {}",
         options: [{ after: true, before: true }],
         errors: [
-            { column: 3, line: 1, type: "Punctuator" },
-            { column: 6, line: 1, type: "Punctuator" }
+            { column: 3, line: 1, type: "Punctuator", messageId: "expectedBefore" },
+            { column: 6, line: 1, type: "Punctuator", messageId: "expectedAfter" }
         ]
     },
     {
@@ -118,8 +118,8 @@ const invalid = [
         output: "a =>a",
         options: [{ after: false, before: true }],
         errors: [
-            { column: 1, line: 1, type: "Identifier" },
-            { column: 5, line: 1, type: "Identifier" }
+            { column: 1, line: 1, type: "Identifier", messageId: "expectedBefore" },
+            { column: 5, line: 1, type: "Identifier", messageId: "unexpectedAfter" }
         ]
     },
     {
@@ -127,8 +127,8 @@ const invalid = [
         output: "() =>{}",
         options: [{ after: false, before: true }],
         errors: [
-            { column: 2, line: 1, type: "Punctuator" },
-            { column: 6, line: 1, type: "Punctuator" }
+            { column: 2, line: 1, type: "Punctuator", messageId: "expectedBefore" },
+            { column: 6, line: 1, type: "Punctuator", messageId: "unexpectedAfter" }
         ]
     },
     {
@@ -136,8 +136,8 @@ const invalid = [
         output: "(a) =>{}",
         options: [{ after: false, before: true }],
         errors: [
-            { column: 3, line: 1, type: "Punctuator" },
-            { column: 7, line: 1, type: "Punctuator" }
+            { column: 3, line: 1, type: "Punctuator", messageId: "expectedBefore" },
+            { column: 7, line: 1, type: "Punctuator", messageId: "unexpectedAfter" }
         ]
     },
     {
@@ -145,8 +145,8 @@ const invalid = [
         output: "a =>a",
         options: [{ after: false, before: true }],
         errors: [
-            { column: 1, line: 1, type: "Identifier" },
-            { column: 6, line: 1, type: "Identifier" }
+            { column: 1, line: 1, type: "Identifier", messageId: "expectedBefore" },
+            { column: 6, line: 1, type: "Identifier", messageId: "unexpectedAfter" }
         ]
     },
     {
@@ -154,8 +154,8 @@ const invalid = [
         output: "() =>{}",
         options: [{ after: false, before: true }],
         errors: [
-            { column: 2, line: 1, type: "Punctuator" },
-            { column: 7, line: 1, type: "Punctuator" }
+            { column: 2, line: 1, type: "Punctuator", messageId: "expectedBefore" },
+            { column: 7, line: 1, type: "Punctuator", messageId: "unexpectedAfter" }
         ]
     },
     {
@@ -163,8 +163,8 @@ const invalid = [
         output: "(a) =>{}",
         options: [{ after: false, before: true }],
         errors: [
-            { column: 3, line: 1, type: "Punctuator" },
-            { column: 8, line: 1, type: "Punctuator" }
+            { column: 3, line: 1, type: "Punctuator", messageId: "expectedBefore" },
+            { column: 8, line: 1, type: "Punctuator", messageId: "unexpectedAfter" }
         ]
     },
     {
@@ -172,8 +172,8 @@ const invalid = [
         output: "a=> a",
         options: [{ after: true, before: false }],
         errors: [
-            { column: 1, line: 1, type: "Identifier" },
-            { column: 5, line: 1, type: "Identifier" }
+            { column: 1, line: 1, type: "Identifier", messageId: "unexpectedBefore" },
+            { column: 5, line: 1, type: "Identifier", messageId: "expectedAfter" }
         ]
     },
     {
@@ -181,8 +181,8 @@ const invalid = [
         output: "()=> {}",
         options: [{ after: true, before: false }],
         errors: [
-            { column: 2, line: 1, type: "Punctuator" },
-            { column: 6, line: 1, type: "Punctuator" }
+            { column: 2, line: 1, type: "Punctuator", messageId: "unexpectedBefore" },
+            { column: 6, line: 1, type: "Punctuator", messageId: "expectedAfter" }
         ]
     },
     {
@@ -190,8 +190,8 @@ const invalid = [
         output: "(a)=> {}",
         options: [{ after: true, before: false }],
         errors: [
-            { column: 3, line: 1, type: "Punctuator" },
-            { column: 7, line: 1, type: "Punctuator" }
+            { column: 3, line: 1, type: "Punctuator", messageId: "unexpectedBefore" },
+            { column: 7, line: 1, type: "Punctuator", messageId: "expectedAfter" }
         ]
     },
     {
@@ -199,8 +199,8 @@ const invalid = [
         output: "a=> a",
         options: [{ after: true, before: false }],
         errors: [
-            { column: 1, line: 1, type: "Identifier" },
-            { column: 6, line: 1, type: "Identifier" }
+            { column: 1, line: 1, type: "Identifier", messageId: "unexpectedBefore" },
+            { column: 6, line: 1, type: "Identifier", messageId: "expectedAfter" }
         ]
     },
     {
@@ -208,8 +208,8 @@ const invalid = [
         output: "()=> {}",
         options: [{ after: true, before: false }],
         errors: [
-            { column: 2, line: 1, type: "Punctuator" },
-            { column: 7, line: 1, type: "Punctuator" }
+            { column: 2, line: 1, type: "Punctuator", messageId: "unexpectedBefore" },
+            { column: 7, line: 1, type: "Punctuator", messageId: "expectedAfter" }
         ]
     },
     {
@@ -217,8 +217,8 @@ const invalid = [
         output: "(a)=> {}",
         options: [{ after: true, before: false }],
         errors: [
-            { column: 3, line: 1, type: "Punctuator" },
-            { column: 8, line: 1, type: "Punctuator" }
+            { column: 3, line: 1, type: "Punctuator", messageId: "unexpectedBefore" },
+            { column: 8, line: 1, type: "Punctuator", messageId: "expectedAfter" }
         ]
     },
     {
@@ -226,8 +226,8 @@ const invalid = [
         output: "a=>a",
         options: [{ after: false, before: false }],
         errors: [
-            { column: 1, line: 1, type: "Identifier" },
-            { column: 6, line: 1, type: "Identifier" }
+            { column: 1, line: 1, type: "Identifier", messageId: "unexpectedBefore" },
+            { column: 6, line: 1, type: "Identifier", messageId: "unexpectedAfter" }
         ]
     },
     {
@@ -235,8 +235,8 @@ const invalid = [
         output: "()=>{}",
         options: [{ after: false, before: false }],
         errors: [
-            { column: 2, line: 1, type: "Punctuator" },
-            { column: 7, line: 1, type: "Punctuator" }
+            { column: 2, line: 1, type: "Punctuator", messageId: "unexpectedBefore" },
+            { column: 7, line: 1, type: "Punctuator", messageId: "unexpectedAfter" }
         ]
     },
     {
@@ -244,8 +244,8 @@ const invalid = [
         output: "(a)=>{}",
         options: [{ after: false, before: false }],
         errors: [
-            { column: 3, line: 1, type: "Punctuator" },
-            { column: 8, line: 1, type: "Punctuator" }
+            { column: 3, line: 1, type: "Punctuator", messageId: "unexpectedBefore" },
+            { column: 8, line: 1, type: "Punctuator", messageId: "unexpectedAfter" }
         ]
     },
     {
@@ -253,8 +253,8 @@ const invalid = [
         output: "a=>a",
         options: [{ after: false, before: false }],
         errors: [
-            { column: 1, line: 1, type: "Identifier" },
-            { column: 8, line: 1, type: "Identifier" }
+            { column: 1, line: 1, type: "Identifier", messageId: "unexpectedBefore" },
+            { column: 8, line: 1, type: "Identifier", messageId: "unexpectedAfter" }
         ]
     },
     {
@@ -262,8 +262,8 @@ const invalid = [
         output: "()=>{}",
         options: [{ after: false, before: false }],
         errors: [
-            { column: 2, line: 1, type: "Punctuator" },
-            { column: 9, line: 1, type: "Punctuator" }
+            { column: 2, line: 1, type: "Punctuator", messageId: "unexpectedBefore" },
+            { column: 9, line: 1, type: "Punctuator", messageId: "unexpectedAfter" }
         ]
     },
     {
@@ -271,8 +271,8 @@ const invalid = [
         output: "(a)=>{}",
         options: [{ after: false, before: false }],
         errors: [
-            { column: 3, line: 1, type: "Punctuator" },
-            { column: 10, line: 1, type: "Punctuator" }
+            { column: 3, line: 1, type: "Punctuator", messageId: "unexpectedBefore" },
+            { column: 10, line: 1, type: "Punctuator", messageId: "unexpectedAfter" }
         ]
     },
     {
@@ -280,7 +280,7 @@ const invalid = [
         output: "(a)  =>{}",
         options: [{ after: false }],
         errors: [
-            { column: 1, line: 2, type: "Punctuator" }
+            { column: 1, line: 2, type: "Punctuator", messageId: "unexpectedAfter" }
         ]
     },
 
@@ -289,20 +289,20 @@ const invalid = [
         code: "(a = ()=>0)=>1",
         output: "(a = () => 0) => 1",
         errors: [
-            { column: 7, line: 1, message: "Missing space before =>." },
-            { column: 10, line: 1, message: "Missing space after =>." },
-            { column: 11, line: 1, message: "Missing space before =>." },
-            { column: 14, line: 1, message: "Missing space after =>." }
+            { column: 7, line: 1, messageId: "expectedBefore" },
+            { column: 10, line: 1, messageId: "expectedAfter" },
+            { column: 11, line: 1, messageId: "expectedBefore" },
+            { column: 14, line: 1, messageId: "expectedAfter" }
         ]
     },
     {
         code: "(a = ()=>0)=>(1)",
         output: "(a = () => 0) => (1)",
         errors: [
-            { column: 7, line: 1, message: "Missing space before =>." },
-            { column: 10, line: 1, message: "Missing space after =>." },
-            { column: 11, line: 1, message: "Missing space before =>." },
-            { column: 14, line: 1, message: "Missing space after =>." }
+            { column: 7, line: 1, messageId: "expectedBefore" },
+            { column: 10, line: 1, messageId: "expectedAfter" },
+            { column: 11, line: 1, messageId: "expectedBefore" },
+            { column: 14, line: 1, messageId: "expectedAfter" }
         ]
     }
 ];
diff --git a/tests/lib/rules/block-scoped-var.js b/tests/lib/rules/block-scoped-var.js
index 75f02f0a455..14803a92255 100644
--- a/tests/lib/rules/block-scoped-var.js
+++ b/tests/lib/rules/block-scoped-var.js
@@ -113,57 +113,57 @@ ruleTester.run("block-scoped-var", rule, {
         { code: "(function () { foo(); })(); function foo() {}", parserOptions: { sourceType: "module" } }
     ],
     invalid: [
-        { code: "function f(){ x; { var x; } }", errors: [{ message: "'x' used outside of binding context.", type: "Identifier" }] },
-        { code: "function f(){ { var x; } x; }", errors: [{ message: "'x' used outside of binding context.", type: "Identifier" }] },
-        { code: "function f() { var a; { var b = 0; } a = b; }", errors: [{ message: "'b' used outside of binding context.", type: "Identifier" }] },
-        { code: "function f() { try { var a = 0; } catch (e) { var b = a; } }", errors: [{ message: "'a' used outside of binding context.", type: "Identifier" }] },
+        { code: "function f(){ x; { var x; } }", errors: [{ messageId: "outOfScope", data: { name: "x" }, type: "Identifier" }] },
+        { code: "function f(){ { var x; } x; }", errors: [{ messageId: "outOfScope", data: { name: "x" }, type: "Identifier" }] },
+        { code: "function f() { var a; { var b = 0; } a = b; }", errors: [{ messageId: "outOfScope", data: { name: "b" }, type: "Identifier" }] },
+        { code: "function f() { try { var a = 0; } catch (e) { var b = a; } }", errors: [{ messageId: "outOfScope", data: { name: "a" }, type: "Identifier" }] },
         {
             code: "function a() { for(var b in {}) { var c = b; } c; }",
-            errors: [{ message: "'c' used outside of binding context.", type: "Identifier" }]
+            errors: [{ messageId: "outOfScope", data: { name: "c" }, type: "Identifier" }]
         },
         {
             code: "function a() { for(var b of {}) { var c = b; } c; }",
             parserOptions: { ecmaVersion: 6 },
-            errors: [{ message: "'c' used outside of binding context.", type: "Identifier" }]
+            errors: [{ messageId: "outOfScope", data: { name: "c" }, type: "Identifier" }]
         },
         {
             code: "function f(){ switch(2) { case 1: var b = 2; b; break; default: b; break;} b; }",
-            errors: [{ message: "'b' used outside of binding context.", type: "Identifier" }]
+            errors: [{ messageId: "outOfScope", data: { name: "b" }, type: "Identifier" }]
         },
         {
             code: "for (var a = 0;;) {} a;",
-            errors: [{ message: "'a' used outside of binding context.", type: "Identifier" }]
+            errors: [{ messageId: "outOfScope", data: { name: "a" }, type: "Identifier" }]
         },
         {
             code: "for (var a in []) {} a;",
-            errors: [{ message: "'a' used outside of binding context.", type: "Identifier" }]
+            errors: [{ messageId: "outOfScope", data: { name: "a" }, type: "Identifier" }]
         },
         {
             code: "for (var a of []) {} a;",
             parserOptions: { ecmaVersion: 6 },
-            errors: [{ message: "'a' used outside of binding context.", type: "Identifier" }]
+            errors: [{ messageId: "outOfScope", data: { name: "a" }, type: "Identifier" }]
         },
         {
             code: "{ var a = 0; } a;",
             parserOptions: { sourceType: "module" },
-            errors: [{ message: "'a' used outside of binding context.", type: "Identifier" }]
+            errors: [{ messageId: "outOfScope", data: { name: "a" }, type: "Identifier" }]
         },
         {
             code: "if (true) { var a; } a;",
-            errors: [{ message: "'a' used outside of binding context.", type: "Identifier" }]
+            errors: [{ messageId: "outOfScope", data: { name: "a" }, type: "Identifier" }]
         },
         {
             code: "if (true) { var a = 1; } else { var a = 2; }",
             errors: [
-                { message: "'a' used outside of binding context.", type: "Identifier" },
-                { message: "'a' used outside of binding context.", type: "Identifier" }
+                { messageId: "outOfScope", data: { name: "a" }, type: "Identifier" },
+                { messageId: "outOfScope", data: { name: "a" }, type: "Identifier" }
             ]
         },
         {
             code: "for (var i = 0;;) {} for(var i = 0;;) {}",
             errors: [
-                { message: "'i' used outside of binding context.", type: "Identifier" },
-                { message: "'i' used outside of binding context.", type: "Identifier" }
+                { messageId: "outOfScope", data: { name: "i" }, type: "Identifier" },
+                { messageId: "outOfScope", data: { name: "i" }, type: "Identifier" }
             ]
         }
     ]
diff --git a/tests/lib/rules/block-spacing.js b/tests/lib/rules/block-spacing.js
index 4b09af6b933..2c1a4a6f932 100644
--- a/tests/lib/rules/block-spacing.js
+++ b/tests/lib/rules/block-spacing.js
@@ -73,100 +73,100 @@ ruleTester.run("block-spacing", rule, {
             output: "{ foo(); }",
             options: ["always"],
             errors: [
-                { type: "BlockStatement", line: 1, column: 1, message: "Requires a space after '{'." },
-                { type: "BlockStatement", line: 1, column: 8, message: "Requires a space before '}'." }
+                { type: "BlockStatement", line: 1, column: 1, messageId: "missing", data: { location: "after", token: "{" } },
+                { type: "BlockStatement", line: 1, column: 8, messageId: "missing", data: { location: "before", token: "}" } }
             ]
         },
         {
             code: "{foo();}",
             output: "{ foo(); }",
             errors: [
-                { type: "BlockStatement", line: 1, column: 1, message: "Requires a space after '{'." },
-                { type: "BlockStatement", line: 1, column: 8, message: "Requires a space before '}'." }
+                { type: "BlockStatement", line: 1, column: 1, messageId: "missing", data: { location: "after", token: "{" } },
+                { type: "BlockStatement", line: 1, column: 8, messageId: "missing", data: { location: "before", token: "}" } }
             ]
         },
         {
             code: "{ foo();}",
             output: "{ foo(); }",
             errors: [
-                { type: "BlockStatement", line: 1, column: 9, message: "Requires a space before '}'." }
+                { type: "BlockStatement", line: 1, column: 9, messageId: "missing", data: { location: "before", token: "}" } }
             ]
         },
         {
             code: "{foo(); }",
             output: "{ foo(); }",
             errors: [
-                { type: "BlockStatement", line: 1, column: 1, message: "Requires a space after '{'." }
+                { type: "BlockStatement", line: 1, column: 1, messageId: "missing", data: { location: "after", token: "{" } }
             ]
         },
         {
             code: "{\nfoo();}",
             output: "{\nfoo(); }",
             errors: [
-                { type: "BlockStatement", line: 2, column: 7, message: "Requires a space before '}'." }
+                { type: "BlockStatement", line: 2, column: 7, messageId: "missing", data: { location: "before", token: "}" } }
             ]
         },
         {
             code: "{foo();\n}",
             output: "{ foo();\n}",
             errors: [
-                { type: "BlockStatement", line: 1, column: 1, message: "Requires a space after '{'." }
+                { type: "BlockStatement", line: 1, column: 1, messageId: "missing", data: { location: "after", token: "{" } }
             ]
         },
         {
             code: "if (a) {foo();}",
             output: "if (a) { foo(); }",
             errors: [
-                { type: "BlockStatement", line: 1, column: 8, message: "Requires a space after '{'." },
-                { type: "BlockStatement", line: 1, column: 15, message: "Requires a space before '}'." }
+                { type: "BlockStatement", line: 1, column: 8, messageId: "missing", data: { location: "after", token: "{" } },
+                { type: "BlockStatement", line: 1, column: 15, messageId: "missing", data: { location: "before", token: "}" } }
             ]
         },
         {
             code: "if (a) {} else {foo();}",
             output: "if (a) {} else { foo(); }",
             errors: [
-                { type: "BlockStatement", line: 1, column: 16, message: "Requires a space after '{'." },
-                { type: "BlockStatement", line: 1, column: 23, message: "Requires a space before '}'." }
+                { type: "BlockStatement", line: 1, column: 16, messageId: "missing", data: { location: "after", token: "{" } },
+                { type: "BlockStatement", line: 1, column: 23, messageId: "missing", data: { location: "before", token: "}" } }
             ]
         },
         {
             code: "switch (a) {case 0: foo();}",
             output: "switch (a) { case 0: foo(); }",
             errors: [
-                { type: "SwitchStatement", line: 1, column: 12, message: "Requires a space after '{'." },
-                { type: "SwitchStatement", line: 1, column: 27, message: "Requires a space before '}'." }
+                { type: "SwitchStatement", line: 1, column: 12, messageId: "missing", data: { location: "after", token: "{" } },
+                { type: "SwitchStatement", line: 1, column: 27, messageId: "missing", data: { location: "before", token: "}" } }
             ]
         },
         {
             code: "while (a) {foo();}",
             output: "while (a) { foo(); }",
             errors: [
-                { type: "BlockStatement", line: 1, column: 11, message: "Requires a space after '{'." },
-                { type: "BlockStatement", line: 1, column: 18, message: "Requires a space before '}'." }
+                { type: "BlockStatement", line: 1, column: 11, messageId: "missing", data: { location: "after", token: "{" } },
+                { type: "BlockStatement", line: 1, column: 18, messageId: "missing", data: { location: "before", token: "}" } }
             ]
         },
         {
             code: "do {foo();} while (a);",
             output: "do { foo(); } while (a);",
             errors: [
-                { type: "BlockStatement", line: 1, column: 4, message: "Requires a space after '{'." },
-                { type: "BlockStatement", line: 1, column: 11, message: "Requires a space before '}'." }
+                { type: "BlockStatement", line: 1, column: 4, messageId: "missing", data: { location: "after", token: "{" } },
+                { type: "BlockStatement", line: 1, column: 11, messageId: "missing", data: { location: "before", token: "}" } }
             ]
         },
         {
             code: "for (;;) {foo();}",
             output: "for (;;) { foo(); }",
             errors: [
-                { type: "BlockStatement", line: 1, column: 10, message: "Requires a space after '{'." },
-                { type: "BlockStatement", line: 1, column: 17, message: "Requires a space before '}'." }
+                { type: "BlockStatement", line: 1, column: 10, messageId: "missing", data: { location: "after", token: "{" } },
+                { type: "BlockStatement", line: 1, column: 17, messageId: "missing", data: { location: "before", token: "}" } }
             ]
         },
         {
             code: "for (var a in b) {foo();}",
             output: "for (var a in b) { foo(); }",
             errors: [
-                { type: "BlockStatement", line: 1, column: 18, message: "Requires a space after '{'." },
-                { type: "BlockStatement", line: 1, column: 25, message: "Requires a space before '}'." }
+                { type: "BlockStatement", line: 1, column: 18, messageId: "missing", data: { location: "after", token: "{" } },
+                { type: "BlockStatement", line: 1, column: 25, messageId: "missing", data: { location: "before", token: "}" } }
             ]
         },
         {
@@ -174,36 +174,36 @@ ruleTester.run("block-spacing", rule, {
             output: "for (var a of b) { foo(); }",
             parserOptions: { ecmaVersion: 6 },
             errors: [
-                { type: "BlockStatement", line: 1, column: 18, message: "Requires a space after '{'." },
-                { type: "BlockStatement", line: 1, column: 25, message: "Requires a space before '}'." }
+                { type: "BlockStatement", line: 1, column: 18, messageId: "missing", data: { location: "after", token: "{" } },
+                { type: "BlockStatement", line: 1, column: 25, messageId: "missing", data: { location: "before", token: "}" } }
             ]
         },
         {
             code: "try {foo();} catch (e) {foo();} finally {foo();}",
             output: "try { foo(); } catch (e) { foo(); } finally { foo(); }",
             errors: [
-                { type: "BlockStatement", line: 1, column: 5, message: "Requires a space after '{'." },
-                { type: "BlockStatement", line: 1, column: 12, message: "Requires a space before '}'." },
-                { type: "BlockStatement", line: 1, column: 24, message: "Requires a space after '{'." },
-                { type: "BlockStatement", line: 1, column: 31, message: "Requires a space before '}'." },
-                { type: "BlockStatement", line: 1, column: 41, message: "Requires a space after '{'." },
-                { type: "BlockStatement", line: 1, column: 48, message: "Requires a space before '}'." }
+                { type: "BlockStatement", line: 1, column: 5, messageId: "missing", data: { location: "after", token: "{" } },
+                { type: "BlockStatement", line: 1, column: 12, messageId: "missing", data: { location: "before", token: "}" } },
+                { type: "BlockStatement", line: 1, column: 24, messageId: "missing", data: { location: "after", token: "{" } },
+                { type: "BlockStatement", line: 1, column: 31, messageId: "missing", data: { location: "before", token: "}" } },
+                { type: "BlockStatement", line: 1, column: 41, messageId: "missing", data: { location: "after", token: "{" } },
+                { type: "BlockStatement", line: 1, column: 48, messageId: "missing", data: { location: "before", token: "}" } }
             ]
         },
         {
             code: "function foo() {bar();}",
             output: "function foo() { bar(); }",
             errors: [
-                { type: "BlockStatement", line: 1, column: 16, message: "Requires a space after '{'." },
-                { type: "BlockStatement", line: 1, column: 23, message: "Requires a space before '}'." }
+                { type: "BlockStatement", line: 1, column: 16, messageId: "missing", data: { location: "after", token: "{" } },
+                { type: "BlockStatement", line: 1, column: 23, messageId: "missing", data: { location: "before", token: "}" } }
             ]
         },
         {
             code: "(function() {bar();});",
             output: "(function() { bar(); });",
             errors: [
-                { type: "BlockStatement", line: 1, column: 13, message: "Requires a space after '{'." },
-                { type: "BlockStatement", line: 1, column: 20, message: "Requires a space before '}'." }
+                { type: "BlockStatement", line: 1, column: 13, messageId: "missing", data: { location: "after", token: "{" } },
+                { type: "BlockStatement", line: 1, column: 20, messageId: "missing", data: { location: "before", token: "}" } }
             ]
         },
         {
@@ -211,8 +211,8 @@ ruleTester.run("block-spacing", rule, {
             output: "(() => { bar(); });",
             parserOptions: { ecmaVersion: 6 },
             errors: [
-                { type: "BlockStatement", line: 1, column: 8, message: "Requires a space after '{'." },
-                { type: "BlockStatement", line: 1, column: 15, message: "Requires a space before '}'." }
+                { type: "BlockStatement", line: 1, column: 8, messageId: "missing", data: { location: "after", token: "{" } },
+                { type: "BlockStatement", line: 1, column: 15, messageId: "missing", data: { location: "before", token: "}" } }
             ]
         },
         {
@@ -220,8 +220,8 @@ ruleTester.run("block-spacing", rule, {
             output: "if (a) { /* comment */ foo(); /* comment */ }",
             parserOptions: { ecmaVersion: 6 },
             errors: [
-                { type: "BlockStatement", line: 1, column: 8, message: "Requires a space after '{'." },
-                { type: "BlockStatement", line: 1, column: 43, message: "Requires a space before '}'." }
+                { type: "BlockStatement", line: 1, column: 8, messageId: "missing", data: { location: "after", token: "{" } },
+                { type: "BlockStatement", line: 1, column: 43, messageId: "missing", data: { location: "before", token: "}" } }
             ]
         },
         {
@@ -229,7 +229,7 @@ ruleTester.run("block-spacing", rule, {
             output: "if (a) { //comment\n foo(); }",
             parserOptions: { ecmaVersion: 6 },
             errors: [
-                { type: "BlockStatement", line: 1, column: 8, message: "Requires a space after '{'." }
+                { type: "BlockStatement", line: 1, column: 8, messageId: "missing", data: { location: "after", token: "{" } }
             ]
         },
 
@@ -240,8 +240,8 @@ ruleTester.run("block-spacing", rule, {
             output: "{foo();}",
             options: ["never"],
             errors: [
-                { type: "BlockStatement", line: 1, column: 1, message: "Unexpected space(s) after '{'." },
-                { type: "BlockStatement", line: 1, column: 10, message: "Unexpected space(s) before '}'." }
+                { type: "BlockStatement", line: 1, column: 1, messageId: "extra", data: { location: "after", token: "{" } },
+                { type: "BlockStatement", line: 1, column: 10, messageId: "extra", data: { location: "before", token: "}" } }
             ]
         },
         {
@@ -249,7 +249,7 @@ ruleTester.run("block-spacing", rule, {
             output: "{foo();}",
             options: ["never"],
             errors: [
-                { type: "BlockStatement", line: 1, column: 1, message: "Unexpected space(s) after '{'." }
+                { type: "BlockStatement", line: 1, column: 1, messageId: "extra", data: { location: "after", token: "{" } }
             ]
         },
         {
@@ -257,7 +257,7 @@ ruleTester.run("block-spacing", rule, {
             output: "{foo();}",
             options: ["never"],
             errors: [
-                { type: "BlockStatement", line: 1, column: 9, message: "Unexpected space(s) before '}'." }
+                { type: "BlockStatement", line: 1, column: 9, messageId: "extra", data: { location: "before", token: "}" } }
             ]
         },
         {
@@ -265,7 +265,7 @@ ruleTester.run("block-spacing", rule, {
             output: "{\nfoo();}",
             options: ["never"],
             errors: [
-                { type: "BlockStatement", line: 2, column: 8, message: "Unexpected space(s) before '}'." }
+                { type: "BlockStatement", line: 2, column: 8, messageId: "extra", data: { location: "before", token: "}" } }
             ]
         },
         {
@@ -273,7 +273,7 @@ ruleTester.run("block-spacing", rule, {
             output: "{foo();\n}",
             options: ["never"],
             errors: [
-                { type: "BlockStatement", line: 1, column: 1, message: "Unexpected space(s) after '{'." }
+                { type: "BlockStatement", line: 1, column: 1, messageId: "extra", data: { location: "after", token: "{" } }
             ]
         },
         {
@@ -281,8 +281,8 @@ ruleTester.run("block-spacing", rule, {
             output: "if (a) {foo();}",
             options: ["never"],
             errors: [
-                { type: "BlockStatement", line: 1, column: 8, message: "Unexpected space(s) after '{'." },
-                { type: "BlockStatement", line: 1, column: 17, message: "Unexpected space(s) before '}'." }
+                { type: "BlockStatement", line: 1, column: 8, messageId: "extra", data: { location: "after", token: "{" } },
+                { type: "BlockStatement", line: 1, column: 17, messageId: "extra", data: { location: "before", token: "}" } }
             ]
         },
         {
@@ -290,8 +290,8 @@ ruleTester.run("block-spacing", rule, {
             output: "if (a) {} else {foo();}",
             options: ["never"],
             errors: [
-                { type: "BlockStatement", line: 1, column: 16, message: "Unexpected space(s) after '{'." },
-                { type: "BlockStatement", line: 1, column: 25, message: "Unexpected space(s) before '}'." }
+                { type: "BlockStatement", line: 1, column: 16, messageId: "extra", data: { location: "after", token: "{" } },
+                { type: "BlockStatement", line: 1, column: 25, messageId: "extra", data: { location: "before", token: "}" } }
             ]
         },
         {
@@ -299,8 +299,8 @@ ruleTester.run("block-spacing", rule, {
             output: "switch (a) {case 0: foo();}",
             options: ["never"],
             errors: [
-                { type: "SwitchStatement", line: 1, column: 12, message: "Unexpected space(s) after '{'." },
-                { type: "SwitchStatement", line: 1, column: 29, message: "Unexpected space(s) before '}'." }
+                { type: "SwitchStatement", line: 1, column: 12, messageId: "extra", data: { location: "after", token: "{" } },
+                { type: "SwitchStatement", line: 1, column: 29, messageId: "extra", data: { location: "before", token: "}" } }
             ]
         },
         {
@@ -308,8 +308,8 @@ ruleTester.run("block-spacing", rule, {
             output: "while (a) {foo();}",
             options: ["never"],
             errors: [
-                { type: "BlockStatement", line: 1, column: 11, message: "Unexpected space(s) after '{'." },
-                { type: "BlockStatement", line: 1, column: 20, message: "Unexpected space(s) before '}'." }
+                { type: "BlockStatement", line: 1, column: 11, messageId: "extra", data: { location: "after", token: "{" } },
+                { type: "BlockStatement", line: 1, column: 20, messageId: "extra", data: { location: "before", token: "}" } }
             ]
         },
         {
@@ -317,8 +317,8 @@ ruleTester.run("block-spacing", rule, {
             output: "do {foo();} while (a);",
             options: ["never"],
             errors: [
-                { type: "BlockStatement", line: 1, column: 4, message: "Unexpected space(s) after '{'." },
-                { type: "BlockStatement", line: 1, column: 13, message: "Unexpected space(s) before '}'." }
+                { type: "BlockStatement", line: 1, column: 4, messageId: "extra", data: { location: "after", token: "{" } },
+                { type: "BlockStatement", line: 1, column: 13, messageId: "extra", data: { location: "before", token: "}" } }
             ]
         },
         {
@@ -326,8 +326,8 @@ ruleTester.run("block-spacing", rule, {
             output: "for (;;) {foo();}",
             options: ["never"],
             errors: [
-                { type: "BlockStatement", line: 1, column: 10, message: "Unexpected space(s) after '{'." },
-                { type: "BlockStatement", line: 1, column: 19, message: "Unexpected space(s) before '}'." }
+                { type: "BlockStatement", line: 1, column: 10, messageId: "extra", data: { location: "after", token: "{" } },
+                { type: "BlockStatement", line: 1, column: 19, messageId: "extra", data: { location: "before", token: "}" } }
             ]
         },
         {
@@ -335,8 +335,8 @@ ruleTester.run("block-spacing", rule, {
             output: "for (var a in b) {foo();}",
             options: ["never"],
             errors: [
-                { type: "BlockStatement", line: 1, column: 18, message: "Unexpected space(s) after '{'." },
-                { type: "BlockStatement", line: 1, column: 27, message: "Unexpected space(s) before '}'." }
+                { type: "BlockStatement", line: 1, column: 18, messageId: "extra", data: { location: "after", token: "{" } },
+                { type: "BlockStatement", line: 1, column: 27, messageId: "extra", data: { location: "before", token: "}" } }
             ]
         },
         {
@@ -345,8 +345,8 @@ ruleTester.run("block-spacing", rule, {
             options: ["never"],
             parserOptions: { ecmaVersion: 6 },
             errors: [
-                { type: "BlockStatement", line: 1, column: 18, message: "Unexpected space(s) after '{'." },
-                { type: "BlockStatement", line: 1, column: 27, message: "Unexpected space(s) before '}'." }
+                { type: "BlockStatement", line: 1, column: 18, messageId: "extra", data: { location: "after", token: "{" } },
+                { type: "BlockStatement", line: 1, column: 27, messageId: "extra", data: { location: "before", token: "}" } }
             ]
         },
         {
@@ -354,12 +354,12 @@ ruleTester.run("block-spacing", rule, {
             output: "try {foo();} catch (e) {foo();} finally {foo();}",
             options: ["never"],
             errors: [
-                { type: "BlockStatement", line: 1, column: 5, message: "Unexpected space(s) after '{'." },
-                { type: "BlockStatement", line: 1, column: 14, message: "Unexpected space(s) before '}'." },
-                { type: "BlockStatement", line: 1, column: 26, message: "Unexpected space(s) after '{'." },
-                { type: "BlockStatement", line: 1, column: 35, message: "Unexpected space(s) before '}'." },
-                { type: "BlockStatement", line: 1, column: 45, message: "Unexpected space(s) after '{'." },
-                { type: "BlockStatement", line: 1, column: 54, message: "Unexpected space(s) before '}'." }
+                { type: "BlockStatement", line: 1, column: 5, messageId: "extra", data: { location: "after", token: "{" } },
+                { type: "BlockStatement", line: 1, column: 14, messageId: "extra", data: { location: "before", token: "}" } },
+                { type: "BlockStatement", line: 1, column: 26, messageId: "extra", data: { location: "after", token: "{" } },
+                { type: "BlockStatement", line: 1, column: 35, messageId: "extra", data: { location: "before", token: "}" } },
+                { type: "BlockStatement", line: 1, column: 45, messageId: "extra", data: { location: "after", token: "{" } },
+                { type: "BlockStatement", line: 1, column: 54, messageId: "extra", data: { location: "before", token: "}" } }
             ]
         },
         {
@@ -367,8 +367,8 @@ ruleTester.run("block-spacing", rule, {
             output: "function foo() {bar();}",
             options: ["never"],
             errors: [
-                { type: "BlockStatement", line: 1, column: 16, message: "Unexpected space(s) after '{'." },
-                { type: "BlockStatement", line: 1, column: 25, message: "Unexpected space(s) before '}'." }
+                { type: "BlockStatement", line: 1, column: 16, messageId: "extra", data: { location: "after", token: "{" } },
+                { type: "BlockStatement", line: 1, column: 25, messageId: "extra", data: { location: "before", token: "}" } }
             ]
         },
         {
@@ -376,8 +376,8 @@ ruleTester.run("block-spacing", rule, {
             output: "(function() {bar();});",
             options: ["never"],
             errors: [
-                { type: "BlockStatement", line: 1, column: 13, message: "Unexpected space(s) after '{'." },
-                { type: "BlockStatement", line: 1, column: 22, message: "Unexpected space(s) before '}'." }
+                { type: "BlockStatement", line: 1, column: 13, messageId: "extra", data: { location: "after", token: "{" } },
+                { type: "BlockStatement", line: 1, column: 22, messageId: "extra", data: { location: "before", token: "}" } }
             ]
         },
         {
@@ -386,8 +386,8 @@ ruleTester.run("block-spacing", rule, {
             options: ["never"],
             parserOptions: { ecmaVersion: 6 },
             errors: [
-                { type: "BlockStatement", line: 1, column: 8, message: "Unexpected space(s) after '{'." },
-                { type: "BlockStatement", line: 1, column: 17, message: "Unexpected space(s) before '}'." }
+                { type: "BlockStatement", line: 1, column: 8, messageId: "extra", data: { location: "after", token: "{" } },
+                { type: "BlockStatement", line: 1, column: 17, messageId: "extra", data: { location: "before", token: "}" } }
             ]
         },
         {
@@ -395,8 +395,8 @@ ruleTester.run("block-spacing", rule, {
             output: "if (a) {/* comment */ foo(); /* comment */}",
             options: ["never"],
             errors: [
-                { type: "BlockStatement", line: 1, column: 8, message: "Unexpected space(s) after '{'." },
-                { type: "BlockStatement", line: 1, column: 45, message: "Unexpected space(s) before '}'." }
+                { type: "BlockStatement", line: 1, column: 8, messageId: "extra", data: { location: "after", token: "{" } },
+                { type: "BlockStatement", line: 1, column: 45, messageId: "extra", data: { location: "before", token: "}" } }
             ]
         }
     ]
diff --git a/tests/lib/rules/brace-style.js b/tests/lib/rules/brace-style.js
index 0b93f9c48b2..33b186731ae 100644
--- a/tests/lib/rules/brace-style.js
+++ b/tests/lib/rules/brace-style.js
@@ -11,12 +11,6 @@
 
 const rule = require("../../../lib/rules/brace-style"),
     RuleTester = require("../../../lib/testers/rule-tester");
-const OPEN_MESSAGE = "Opening curly brace does not appear on the same line as controlling statement.",
-    OPEN_MESSAGE_ALLMAN = "Opening curly brace appears on the same line as controlling statement.",
-    BODY_MESSAGE = "Statement inside of curly braces should be on next line.",
-    CLOSE_MESSAGE = "Closing curly brace does not appear on the same line as the subsequent block.",
-    CLOSE_MESSAGE_SINGLE = "Closing curly brace should be on the same line as opening curly brace or on the line after the previous block.",
-    CLOSE_MESSAGE_STROUSTRUP_ALLMAN = "Closing curly brace appears on the same line as the subsequent block.";
 
 //------------------------------------------------------------------------------
 // Tests
@@ -201,143 +195,143 @@ ruleTester.run("brace-style", rule, {
         {
             code: "if (f) {\nbar;\n}\nelse\nbaz;",
             output: "if (f) {\nbar;\n} else\nbaz;",
-            errors: [{ message: CLOSE_MESSAGE, type: "Punctuator" }]
+            errors: [{ messageId: "nextLineClose", type: "Punctuator" }]
         },
         {
             code: "var foo = () => { return; }",
             output: "var foo = () => {\n return; \n}",
             parserOptions: { ecmaVersion: 6 },
-            errors: [{ message: BODY_MESSAGE, type: "Punctuator" }, { message: CLOSE_MESSAGE_SINGLE, type: "Punctuator" }]
+            errors: [{ messageId: "blockSameLine", type: "Punctuator" }, { messageId: "singleLineClose", type: "Punctuator" }]
         },
         {
             code: "function foo() { return; }",
             output: "function foo() {\n return; \n}",
-            errors: [{ message: BODY_MESSAGE, type: "Punctuator" }, { message: CLOSE_MESSAGE_SINGLE, type: "Punctuator" }]
+            errors: [{ messageId: "blockSameLine", type: "Punctuator" }, { messageId: "singleLineClose", type: "Punctuator" }]
         },
         {
             code: "function foo() \n { \n return; }",
             output: "function foo() { \n return; \n}",
-            errors: [{ message: OPEN_MESSAGE, type: "Punctuator" }, { message: CLOSE_MESSAGE_SINGLE, type: "Punctuator" }]
+            errors: [{ messageId: "nextLineOpen", type: "Punctuator" }, { messageId: "singleLineClose", type: "Punctuator" }]
         },
         {
             code: "!function foo() \n { \n return; }",
             output: "!function foo() { \n return; \n}",
-            errors: [{ message: OPEN_MESSAGE, type: "Punctuator" }, { message: CLOSE_MESSAGE_SINGLE, type: "Punctuator" }]
+            errors: [{ messageId: "nextLineOpen", type: "Punctuator" }, { messageId: "singleLineClose", type: "Punctuator" }]
         },
         {
             code: "if (foo) \n { \n bar(); }",
             output: "if (foo) { \n bar(); \n}",
-            errors: [{ message: OPEN_MESSAGE, type: "Punctuator" }, { message: CLOSE_MESSAGE_SINGLE, type: "Punctuator" }]
+            errors: [{ messageId: "nextLineOpen", type: "Punctuator" }, { messageId: "singleLineClose", type: "Punctuator" }]
         },
         {
             code: "if (a) { \nb();\n } else \n { c(); }",
             output: "if (a) { \nb();\n } else {\n c(); \n}",
-            errors: [{ message: OPEN_MESSAGE, type: "Punctuator" }, { message: BODY_MESSAGE, type: "Punctuator" }, { message: CLOSE_MESSAGE_SINGLE, type: "Punctuator" }]
+            errors: [{ messageId: "nextLineOpen", type: "Punctuator" }, { messageId: "blockSameLine", type: "Punctuator" }, { messageId: "singleLineClose", type: "Punctuator" }]
         },
         {
             code: "while (foo) \n { \n bar(); }",
             output: "while (foo) { \n bar(); \n}",
-            errors: [{ message: OPEN_MESSAGE, type: "Punctuator" }, { message: CLOSE_MESSAGE_SINGLE, type: "Punctuator" }]
+            errors: [{ messageId: "nextLineOpen", type: "Punctuator" }, { messageId: "singleLineClose", type: "Punctuator" }]
         },
         {
             code: "for (;;) \n { \n bar(); }",
             output: "for (;;) { \n bar(); \n}",
-            errors: [{ message: OPEN_MESSAGE, type: "Punctuator" }, { message: CLOSE_MESSAGE_SINGLE, type: "Punctuator" }]
+            errors: [{ messageId: "nextLineOpen", type: "Punctuator" }, { messageId: "singleLineClose", type: "Punctuator" }]
         },
         {
             code: "with (foo) \n { \n bar(); }",
             output: "with (foo) { \n bar(); \n}",
-            errors: [{ message: OPEN_MESSAGE, type: "Punctuator" }, { message: CLOSE_MESSAGE_SINGLE, type: "Punctuator" }]
+            errors: [{ messageId: "nextLineOpen", type: "Punctuator" }, { messageId: "singleLineClose", type: "Punctuator" }]
         },
         {
             code: "switch (foo) \n { \n case \"bar\": break; }",
             output: "switch (foo) { \n case \"bar\": break; \n}",
-            errors: [{ message: OPEN_MESSAGE, type: "Punctuator" }, { message: CLOSE_MESSAGE_SINGLE, type: "Punctuator" }]
+            errors: [{ messageId: "nextLineOpen", type: "Punctuator" }, { messageId: "singleLineClose", type: "Punctuator" }]
         },
         {
             code: "switch (foo) \n { }",
             output: "switch (foo) { }",
-            errors: [{ message: OPEN_MESSAGE, type: "Punctuator" }]
+            errors: [{ messageId: "nextLineOpen", type: "Punctuator" }]
         },
         {
             code: "try \n { \n bar(); \n } catch (e) {}",
             output: "try { \n bar(); \n } catch (e) {}",
-            errors: [{ message: OPEN_MESSAGE, type: "Punctuator" }]
+            errors: [{ messageId: "nextLineOpen", type: "Punctuator" }]
         },
         {
             code: "try { \n bar(); \n } catch (e) \n {}",
             output: "try { \n bar(); \n } catch (e) {}",
-            errors: [{ message: OPEN_MESSAGE, type: "Punctuator" }]
+            errors: [{ messageId: "nextLineOpen", type: "Punctuator" }]
         },
         {
             code: "do \n { \n bar(); \n} while (true)",
             output: "do { \n bar(); \n} while (true)",
-            errors: [{ message: OPEN_MESSAGE, type: "Punctuator" }]
+            errors: [{ messageId: "nextLineOpen", type: "Punctuator" }]
         },
         {
             code: "for (foo in bar) \n { \n baz(); \n }",
             output: "for (foo in bar) { \n baz(); \n }",
-            errors: [{ message: OPEN_MESSAGE, type: "Punctuator" }]
+            errors: [{ messageId: "nextLineOpen", type: "Punctuator" }]
         },
         {
             code: "for (foo of bar) \n { \n baz(); \n }",
             output: "for (foo of bar) { \n baz(); \n }",
             parserOptions: { ecmaVersion: 6 },
-            errors: [{ message: OPEN_MESSAGE, type: "Punctuator" }]
+            errors: [{ messageId: "nextLineOpen", type: "Punctuator" }]
         },
         {
             code: "try { \n bar(); \n }\ncatch (e) {\n}",
             output: "try { \n bar(); \n } catch (e) {\n}",
-            errors: [{ message: CLOSE_MESSAGE, type: "Punctuator" }]
+            errors: [{ messageId: "nextLineClose", type: "Punctuator" }]
         },
         {
             code: "try { \n bar(); \n } catch (e) {\n}\n finally {\n}",
             output: "try { \n bar(); \n } catch (e) {\n} finally {\n}",
-            errors: [{ message: CLOSE_MESSAGE, type: "Punctuator" }]
+            errors: [{ messageId: "nextLineClose", type: "Punctuator" }]
         },
         {
             code: "if (a) { \nb();\n } \n else { \nc();\n }",
             output: "if (a) { \nb();\n } else { \nc();\n }",
-            errors: [{ message: CLOSE_MESSAGE, type: "Punctuator" }]
+            errors: [{ messageId: "nextLineClose", type: "Punctuator" }]
         },
         {
             code: "try { \n bar(); \n }\ncatch (e) {\n} finally {\n}",
             output: "try { \n bar(); \n }\ncatch (e) {\n}\n finally {\n}",
             options: ["stroustrup"],
-            errors: [{ message: CLOSE_MESSAGE_STROUSTRUP_ALLMAN, type: "Punctuator" }]
+            errors: [{ messageId: "sameLineClose", type: "Punctuator" }]
         },
         {
             code: "try { \n bar(); \n } catch (e) {\n}\n finally {\n}",
             output: "try { \n bar(); \n }\n catch (e) {\n}\n finally {\n}",
             options: ["stroustrup"],
-            errors: [{ message: CLOSE_MESSAGE_STROUSTRUP_ALLMAN, type: "Punctuator" }]
+            errors: [{ messageId: "sameLineClose", type: "Punctuator" }]
         },
         {
             code: "if (a) { \nb();\n } else { \nc();\n }",
             output: "if (a) { \nb();\n }\n else { \nc();\n }",
             options: ["stroustrup"],
-            errors: [{ message: CLOSE_MESSAGE_STROUSTRUP_ALLMAN, type: "Punctuator" }]
+            errors: [{ messageId: "sameLineClose", type: "Punctuator" }]
         },
         {
             code: "if (foo) {\nbaz();\n} else if (bar) {\nbaz();\n}\nelse {\nqux();\n}",
             output: "if (foo) {\nbaz();\n}\n else if (bar) {\nbaz();\n}\nelse {\nqux();\n}",
             options: ["stroustrup"],
-            errors: [{ message: CLOSE_MESSAGE_STROUSTRUP_ALLMAN, type: "Punctuator" }]
+            errors: [{ messageId: "sameLineClose", type: "Punctuator" }]
         },
         {
             code: "if (foo) {\npoop();\n} \nelse if (bar) {\nbaz();\n} else if (thing) {\nboom();\n}\nelse {\nqux();\n}",
             output: "if (foo) {\npoop();\n} \nelse if (bar) {\nbaz();\n}\n else if (thing) {\nboom();\n}\nelse {\nqux();\n}",
             options: ["stroustrup"],
-            errors: [{ message: CLOSE_MESSAGE_STROUSTRUP_ALLMAN, type: "Punctuator" }]
+            errors: [{ messageId: "sameLineClose", type: "Punctuator" }]
         },
         {
             code: "try { \n bar(); \n }\n catch (e) {\n}\n finally {\n}",
             output: "try \n{ \n bar(); \n }\n catch (e) \n{\n}\n finally \n{\n}",
             options: ["allman"],
             errors: [
-                { message: OPEN_MESSAGE_ALLMAN, type: "Punctuator", line: 1 },
-                { message: OPEN_MESSAGE_ALLMAN, type: "Punctuator", line: 4 },
-                { message: OPEN_MESSAGE_ALLMAN, type: "Punctuator", line: 6 }
+                { messageId: "sameLineOpen", type: "Punctuator", line: 1 },
+                { messageId: "sameLineOpen", type: "Punctuator", line: 4 },
+                { messageId: "sameLineOpen", type: "Punctuator", line: 6 }
             ]
         },
         {
@@ -345,9 +339,9 @@ ruleTester.run("brace-style", rule, {
             output: "switch(x) \n{\n case 1: \nbar(); \n}\n ",
             options: ["allman"],
             errors: [
-                { message: OPEN_MESSAGE_ALLMAN, type: "Punctuator", line: 1 },
-                { message: BODY_MESSAGE, type: "Punctuator", line: 1 },
-                { message: CLOSE_MESSAGE_SINGLE, type: "Punctuator", line: 2 }
+                { messageId: "sameLineOpen", type: "Punctuator", line: 1 },
+                { messageId: "blockSameLine", type: "Punctuator", line: 1 },
+                { messageId: "singleLineClose", type: "Punctuator", line: 2 }
             ]
         },
         {
@@ -355,9 +349,9 @@ ruleTester.run("brace-style", rule, {
             output: "if (a) \n{ \nb();\n }\n else \n{ \nc();\n }",
             options: ["allman"],
             errors: [
-                { message: OPEN_MESSAGE_ALLMAN, type: "Punctuator" },
-                { message: CLOSE_MESSAGE_STROUSTRUP_ALLMAN, type: "Punctuator" },
-                { message: OPEN_MESSAGE_ALLMAN, type: "Punctuator" }
+                { messageId: "sameLineOpen", type: "Punctuator" },
+                { messageId: "sameLineClose", type: "Punctuator" },
+                { messageId: "sameLineOpen", type: "Punctuator" }
             ]
         },
         {
@@ -365,10 +359,10 @@ ruleTester.run("brace-style", rule, {
             output: "if (foo) \n{\nbaz();\n}\n else if (bar) \n{\nbaz();\n}\nelse \n{\nqux();\n}",
             options: ["allman"],
             errors: [
-                { message: OPEN_MESSAGE_ALLMAN, type: "Punctuator" },
-                { message: CLOSE_MESSAGE_STROUSTRUP_ALLMAN, type: "Punctuator" },
-                { message: OPEN_MESSAGE_ALLMAN, type: "Punctuator" },
-                { message: OPEN_MESSAGE_ALLMAN, type: "Punctuator" }
+                { messageId: "sameLineOpen", type: "Punctuator" },
+                { messageId: "sameLineClose", type: "Punctuator" },
+                { messageId: "sameLineOpen", type: "Punctuator" },
+                { messageId: "sameLineOpen", type: "Punctuator" }
             ]
         },
         {
@@ -376,11 +370,11 @@ ruleTester.run("brace-style", rule, {
             output: "if (foo)\n{\n poop();\n} \nelse if (bar) \n{\nbaz();\n}\n else if (thing) \n{\nboom();\n}\nelse \n{\nqux();\n}",
             options: ["allman"],
             errors: [
-                { message: BODY_MESSAGE, type: "Punctuator" },
-                { message: OPEN_MESSAGE_ALLMAN, type: "Punctuator" },
-                { message: CLOSE_MESSAGE_STROUSTRUP_ALLMAN, type: "Punctuator" },
-                { message: OPEN_MESSAGE_ALLMAN, type: "Punctuator" },
-                { message: OPEN_MESSAGE_ALLMAN, type: "Punctuator" }
+                { messageId: "blockSameLine", type: "Punctuator" },
+                { messageId: "sameLineOpen", type: "Punctuator" },
+                { messageId: "sameLineClose", type: "Punctuator" },
+                { messageId: "sameLineOpen", type: "Punctuator" },
+                { messageId: "sameLineOpen", type: "Punctuator" }
             ]
         },
         {
@@ -388,7 +382,7 @@ ruleTester.run("brace-style", rule, {
             output: "if (foo)\n{\n  bar(); \n}",
             options: ["allman"],
             errors: [
-                { message: CLOSE_MESSAGE_SINGLE, type: "Punctuator" }
+                { messageId: "singleLineClose", type: "Punctuator" }
             ]
         },
         {
@@ -396,7 +390,7 @@ ruleTester.run("brace-style", rule, {
             output: "try\n{\n  somethingRisky();\n}\n catch (e)\n{\n  handleError()\n}",
             options: ["allman"],
             errors: [
-                { message: CLOSE_MESSAGE_STROUSTRUP_ALLMAN, type: "Punctuator" }
+                { messageId: "sameLineClose", type: "Punctuator" }
             ]
         },
 
@@ -405,150 +399,150 @@ ruleTester.run("brace-style", rule, {
             code: "function foo() { return; \n}",
             output: "function foo() {\n return; \n}",
             options: ["1tbs", { allowSingleLine: true }],
-            errors: [{ message: BODY_MESSAGE, type: "Punctuator" }]
+            errors: [{ messageId: "blockSameLine", type: "Punctuator" }]
         },
         {
             code: "function foo() { a(); b(); return; \n}",
             output: "function foo() {\n a(); b(); return; \n}",
             options: ["1tbs", { allowSingleLine: true }],
-            errors: [{ message: BODY_MESSAGE, type: "Punctuator" }]
+            errors: [{ messageId: "blockSameLine", type: "Punctuator" }]
         },
         {
             code: "function foo() { \n return; }",
             output: "function foo() { \n return; \n}",
             options: ["1tbs", { allowSingleLine: true }],
-            errors: [{ message: CLOSE_MESSAGE_SINGLE, type: "Punctuator" }]
+            errors: [{ messageId: "singleLineClose", type: "Punctuator" }]
         },
         {
             code: "function foo() {\na();\nb();\nreturn; }",
             output: "function foo() {\na();\nb();\nreturn; \n}",
             options: ["1tbs", { allowSingleLine: true }],
-            errors: [{ message: CLOSE_MESSAGE_SINGLE, type: "Punctuator" }]
+            errors: [{ messageId: "singleLineClose", type: "Punctuator" }]
         },
         {
             code: "!function foo() { \n return; }",
             output: "!function foo() { \n return; \n}",
             options: ["1tbs", { allowSingleLine: true }],
-            errors: [{ message: CLOSE_MESSAGE_SINGLE, type: "Punctuator" }]
+            errors: [{ messageId: "singleLineClose", type: "Punctuator" }]
         },
         {
             code: "if (a) { b();\n } else { c(); }",
             output: "if (a) {\n b();\n } else { c(); }",
             options: ["1tbs", { allowSingleLine: true }],
-            errors: [{ message: BODY_MESSAGE, type: "Punctuator" }]
+            errors: [{ messageId: "blockSameLine", type: "Punctuator" }]
         },
         {
             code: "if (a) { b(); }\nelse { c(); }",
             output: "if (a) { b(); } else { c(); }",
             options: ["1tbs", { allowSingleLine: true }],
-            errors: [{ message: CLOSE_MESSAGE, type: "Punctuator" }]
+            errors: [{ messageId: "nextLineClose", type: "Punctuator" }]
         },
         {
             code: "while (foo) { \n bar(); }",
             output: "while (foo) { \n bar(); \n}",
             options: ["1tbs", { allowSingleLine: true }],
-            errors: [{ message: CLOSE_MESSAGE_SINGLE, type: "Punctuator" }]
+            errors: [{ messageId: "singleLineClose", type: "Punctuator" }]
         },
         {
             code: "for (;;) { bar(); \n }",
             output: "for (;;) {\n bar(); \n }",
             options: ["1tbs", { allowSingleLine: true }],
-            errors: [{ message: BODY_MESSAGE, type: "Punctuator" }]
+            errors: [{ messageId: "blockSameLine", type: "Punctuator" }]
         },
         {
             code: "with (foo) { bar(); \n }",
             output: "with (foo) {\n bar(); \n }",
             options: ["1tbs", { allowSingleLine: true }],
-            errors: [{ message: BODY_MESSAGE, type: "Punctuator" }]
+            errors: [{ messageId: "blockSameLine", type: "Punctuator" }]
         },
         {
             code: "switch (foo) \n { \n case \"bar\": break; }",
             output: "switch (foo) { \n case \"bar\": break; \n}",
             options: ["1tbs", { allowSingleLine: true }],
-            errors: [{ message: OPEN_MESSAGE, type: "Punctuator" }, { message: CLOSE_MESSAGE_SINGLE, type: "Punctuator" }]
+            errors: [{ messageId: "nextLineOpen", type: "Punctuator" }, { messageId: "singleLineClose", type: "Punctuator" }]
         },
         {
             code: "switch (foo) \n { }",
             output: "switch (foo) { }",
             options: ["1tbs", { allowSingleLine: true }],
-            errors: [{ message: OPEN_MESSAGE, type: "Punctuator" }]
+            errors: [{ messageId: "nextLineOpen", type: "Punctuator" }]
         },
         {
             code: "try {  bar(); }\ncatch (e) { baz();  }",
             output: "try {  bar(); } catch (e) { baz();  }",
             options: ["1tbs", { allowSingleLine: true }],
-            errors: [{ message: CLOSE_MESSAGE, type: "Punctuator" }]
+            errors: [{ messageId: "nextLineClose", type: "Punctuator" }]
         },
         {
             code: "try \n { \n bar(); \n } catch (e) {}",
             output: "try { \n bar(); \n } catch (e) {}",
             options: ["1tbs", { allowSingleLine: true }],
-            errors: [{ message: OPEN_MESSAGE, type: "Punctuator" }]
+            errors: [{ messageId: "nextLineOpen", type: "Punctuator" }]
         },
         {
             code: "try { \n bar(); \n } catch (e) \n {}",
             output: "try { \n bar(); \n } catch (e) {}",
             options: ["1tbs", { allowSingleLine: true }],
-            errors: [{ message: OPEN_MESSAGE, type: "Punctuator" }]
+            errors: [{ messageId: "nextLineOpen", type: "Punctuator" }]
         },
         {
             code: "do \n { \n bar(); \n} while (true)",
             output: "do { \n bar(); \n} while (true)",
             options: ["1tbs", { allowSingleLine: true }],
-            errors: [{ message: OPEN_MESSAGE, type: "Punctuator" }]
+            errors: [{ messageId: "nextLineOpen", type: "Punctuator" }]
         },
         {
             code: "for (foo in bar) \n { \n baz(); \n }",
             output: "for (foo in bar) { \n baz(); \n }",
             options: ["1tbs", { allowSingleLine: true }],
-            errors: [{ message: OPEN_MESSAGE, type: "Punctuator" }]
+            errors: [{ messageId: "nextLineOpen", type: "Punctuator" }]
         },
         {
             code: "try { \n bar(); \n }\ncatch (e) {\n}",
             output: "try { \n bar(); \n } catch (e) {\n}",
             options: ["1tbs", { allowSingleLine: true }],
-            errors: [{ message: CLOSE_MESSAGE, type: "Punctuator" }]
+            errors: [{ messageId: "nextLineClose", type: "Punctuator" }]
         },
         {
             code: "try { \n bar(); \n } catch (e) {\n}\n finally {\n}",
             output: "try { \n bar(); \n } catch (e) {\n} finally {\n}",
             options: ["1tbs", { allowSingleLine: true }],
-            errors: [{ message: CLOSE_MESSAGE, type: "Punctuator" }]
+            errors: [{ messageId: "nextLineClose", type: "Punctuator" }]
         },
         {
             code: "if (a) { \nb();\n } \n else { \nc();\n }",
             output: "if (a) { \nb();\n } else { \nc();\n }",
             options: ["1tbs", { allowSingleLine: true }],
-            errors: [{ message: CLOSE_MESSAGE, type: "Punctuator" }]
+            errors: [{ messageId: "nextLineClose", type: "Punctuator" }]
         },
         {
             code: "try { \n bar(); \n }\ncatch (e) {\n} finally {\n}",
             output: "try { \n bar(); \n }\ncatch (e) {\n}\n finally {\n}",
             options: ["stroustrup", { allowSingleLine: true }],
-            errors: [{ message: CLOSE_MESSAGE_STROUSTRUP_ALLMAN, type: "Punctuator" }]
+            errors: [{ messageId: "sameLineClose", type: "Punctuator" }]
         },
         {
             code: "try { \n bar(); \n } catch (e) {\n}\n finally {\n}",
             output: "try { \n bar(); \n }\n catch (e) {\n}\n finally {\n}",
             options: ["stroustrup", { allowSingleLine: true }],
-            errors: [{ message: CLOSE_MESSAGE_STROUSTRUP_ALLMAN, type: "Punctuator" }]
+            errors: [{ messageId: "sameLineClose", type: "Punctuator" }]
         },
         {
             code: "if (a) { \nb();\n } else { \nc();\n }",
             output: "if (a) { \nb();\n }\n else { \nc();\n }",
             options: ["stroustrup", { allowSingleLine: true }],
-            errors: [{ message: CLOSE_MESSAGE_STROUSTRUP_ALLMAN, type: "Punctuator" }]
+            errors: [{ messageId: "sameLineClose", type: "Punctuator" }]
         },
         {
             code: "if (foo)\n{ poop();\n} \nelse if (bar) {\nbaz();\n} else if (thing) {\nboom();\n}\nelse {\nqux();\n}",
             output: "if (foo)\n{\n poop();\n} \nelse if (bar) \n{\nbaz();\n}\n else if (thing) \n{\nboom();\n}\nelse \n{\nqux();\n}",
             options: ["allman", { allowSingleLine: true }],
             errors: [
-                { message: BODY_MESSAGE, type: "Punctuator" },
-                { message: OPEN_MESSAGE_ALLMAN, type: "Punctuator" },
-                { message: CLOSE_MESSAGE_STROUSTRUP_ALLMAN, type: "Punctuator" },
-                { message: OPEN_MESSAGE_ALLMAN, type: "Punctuator" },
-                { message: OPEN_MESSAGE_ALLMAN, type: "Punctuator" }
+                { messageId: "blockSameLine", type: "Punctuator" },
+                { messageId: "sameLineOpen", type: "Punctuator" },
+                { messageId: "sameLineClose", type: "Punctuator" },
+                { messageId: "sameLineOpen", type: "Punctuator" },
+                { messageId: "sameLineOpen", type: "Punctuator" }
             ]
         },
 
@@ -556,80 +550,80 @@ ruleTester.run("brace-style", rule, {
         {
             code: "if (foo) // comment \n{\nbar();\n}",
             output: null,
-            errors: [{ message: OPEN_MESSAGE, type: "Punctuator" }]
+            errors: [{ messageId: "nextLineOpen", type: "Punctuator" }]
         },
 
         // https://github.com/eslint/eslint/issues/7493
         {
             code: "if (foo) {\n bar\n.baz }",
             output: "if (foo) {\n bar\n.baz \n}",
-            errors: [{ message: CLOSE_MESSAGE_SINGLE, type: "Punctuator" }]
+            errors: [{ messageId: "singleLineClose", type: "Punctuator" }]
         },
         {
             code: "if (foo)\n{\n bar\n.baz }",
             output: "if (foo)\n{\n bar\n.baz \n}",
             options: ["allman"],
-            errors: [{ message: CLOSE_MESSAGE_SINGLE, type: "Punctuator" }]
+            errors: [{ messageId: "singleLineClose", type: "Punctuator" }]
         },
         {
             code: "if (foo) { bar\n.baz }",
             output: "if (foo) {\n bar\n.baz \n}",
             options: ["1tbs", { allowSingleLine: true }],
-            errors: [{ message: BODY_MESSAGE, type: "Punctuator" }, { message: CLOSE_MESSAGE_SINGLE, type: "Punctuator" }]
+            errors: [{ messageId: "blockSameLine", type: "Punctuator" }, { messageId: "singleLineClose", type: "Punctuator" }]
         },
         {
             code: "if (foo) { bar\n.baz }",
             output: "if (foo) \n{\n bar\n.baz \n}",
             options: ["allman", { allowSingleLine: true }],
             errors: [
-                { message: OPEN_MESSAGE_ALLMAN, type: "Punctuator" },
-                { message: BODY_MESSAGE, type: "Punctuator" },
-                { message: CLOSE_MESSAGE_SINGLE, type: "Punctuator" }
+                { messageId: "sameLineOpen", type: "Punctuator" },
+                { messageId: "blockSameLine", type: "Punctuator" },
+                { messageId: "singleLineClose", type: "Punctuator" }
             ]
         },
         {
             code: "switch (x) {\n case 1: foo() }",
             output: "switch (x) {\n case 1: foo() \n}",
             options: ["1tbs", { allowSingleLine: true }],
-            errors: [{ message: CLOSE_MESSAGE_SINGLE, type: "Punctuator" }]
+            errors: [{ messageId: "singleLineClose", type: "Punctuator" }]
         },
         {
             code: "class Foo\n{\n}",
             output: "class Foo {\n}",
-            errors: [{ message: OPEN_MESSAGE, type: "Punctuator" }]
+            errors: [{ messageId: "nextLineOpen", type: "Punctuator" }]
         },
         {
             code: "(class\n{\n})",
             output: "(class {\n})",
-            errors: [{ message: OPEN_MESSAGE, type: "Punctuator" }]
+            errors: [{ messageId: "nextLineOpen", type: "Punctuator" }]
         },
         {
             code: "class Foo{\n}",
             output: "class Foo\n{\n}",
             options: ["allman"],
-            errors: [{ message: OPEN_MESSAGE_ALLMAN, type: "Punctuator" }]
+            errors: [{ messageId: "sameLineOpen", type: "Punctuator" }]
         },
         {
             code: "(class {\n})",
             output: "(class \n{\n})",
             options: ["allman"],
-            errors: [{ message: OPEN_MESSAGE_ALLMAN, type: "Punctuator" }]
+            errors: [{ messageId: "sameLineOpen", type: "Punctuator" }]
         },
         {
             code: "class Foo {\nbar() {\n}}",
             output: "class Foo {\nbar() {\n}\n}",
-            errors: [{ message: CLOSE_MESSAGE_SINGLE, type: "Punctuator" }]
+            errors: [{ messageId: "singleLineClose", type: "Punctuator" }]
         },
         {
             code: "(class Foo {\nbar() {\n}})",
             output: "(class Foo {\nbar() {\n}\n})",
-            errors: [{ message: CLOSE_MESSAGE_SINGLE, type: "Punctuator" }]
+            errors: [{ messageId: "singleLineClose", type: "Punctuator" }]
         },
         {
             code: "class\nFoo{}",
             output: "class\nFoo\n{}",
             options: ["allman"],
-            errors: [{ message: OPEN_MESSAGE_ALLMAN, type: "Punctuator" }]
+            errors: [{ messageId: "sameLineOpen", type: "Punctuator" }]
         },
 
         // https://github.com/eslint/eslint/issues/7621
@@ -651,8 +645,8 @@ ruleTester.run("brace-style", rule, {
                 }
             `,
             errors: [
-                { message: OPEN_MESSAGE, type: "Punctuator" },
-                { message: CLOSE_MESSAGE, type: "Punctuator" }
+                { messageId: "nextLineOpen", type: "Punctuator" },
+                { messageId: "nextLineClose", type: "Punctuator" }
             ]
         }
     ]
diff --git a/tests/lib/rules/callback-return.js b/tests/lib/rules/callback-return.js
index 29f98136b41..1e178915d0a 100644
--- a/tests/lib/rules/callback-return.js
+++ b/tests/lib/rules/callback-return.js
@@ -12,10 +12,9 @@ const rule = require("../../../lib/rules/callback-return"),
     RuleTester = require("../../../lib/testers/rule-tester");
 
 //------------------------------------------------------------------------------
-// Helpers
+// Tests
 //------------------------------------------------------------------------------
 
-
 const ruleTester = new RuleTester();
 
 ruleTester.run("callback-return", rule, {
@@ -157,7 +156,7 @@ ruleTester.run("callback-return", rule, {
         {
             code: "function a(err) { if (err) { callback (err); } }",
             errors: [{
-                message: "Expected return with your callback function.",
+                messageId: "missingReturn",
                 line: 1,
                 column: 30,
                 nodeType: "CallExpression"
@@ -166,7 +165,7 @@ ruleTester.run("callback-return", rule, {
         {
             code: "function a(callback) { if (typeof callback !== 'undefined') { callback(); } }",
             errors: [{
-                message: "Expected return with your callback function.",
+                messageId: "missingReturn",
                 line: 1,
                 column: 63,
                 nodeType: "CallExpression"
@@ -175,7 +174,7 @@ ruleTester.run("callback-return", rule, {
         {
             code: "function a(callback) { if (typeof callback !== 'undefined') callback();  }",
             errors: [{
-                message: "Expected return with your callback function.",
+                messageId: "missingReturn",
                 line: 1,
                 column: 61,
                 nodeType: "CallExpression"
@@ -184,7 +183,7 @@ ruleTester.run("callback-return", rule, {
         {
             code: "function a(callback) { if (err) { callback(); horse && horse(); } }",
             errors: [{
-                message: "Expected return with your callback function.",
+                messageId: "missingReturn",
                 line: 1,
                 column: 35,
                 nodeType: "CallExpression"
@@ -194,7 +193,7 @@ ruleTester.run("callback-return", rule, {
             code: "var x = (err) => { if (err) { callback (err); } }",
             parserOptions: { ecmaVersion: 6 },
             errors: [{
-                message: "Expected return with your callback function.",
+                messageId: "missingReturn",
                 line: 1,
                 column: 31,
                 nodeType: "CallExpression"
@@ -204,7 +203,7 @@ ruleTester.run("callback-return", rule, {
             code: "var x = { x(err) { if (err) { callback (err); } } }",
             parserOptions: { ecmaVersion: 6 },
             errors: [{
-                message: "Expected return with your callback function.",
+                messageId: "missingReturn",
                 line: 1,
                 column: 31,
                 nodeType: "CallExpression"
@@ -213,7 +212,7 @@ ruleTester.run("callback-return", rule, {
         {
             code: "function x(err) { if (err) {\n log();\n callback(err); } }",
             errors: [{
-                message: "Expected return with your callback function.",
+                messageId: "missingReturn",
                 line: 3,
                 column: 2,
                 nodeType: "CallExpression"
@@ -223,7 +222,7 @@ ruleTester.run("callback-return", rule, {
             code: "var x = { x(err) { if (err) { callback && callback (err); } } }",
             parserOptions: { ecmaVersion: 6 },
             errors: [{
-                message: "Expected return with your callback function.",
+                messageId: "missingReturn",
                 line: 1,
                 column: 43,
                 nodeType: "CallExpression"
@@ -232,7 +231,7 @@ ruleTester.run("callback-return", rule, {
         {
             code: "function a(err) { callback (err); callback(); }",
             errors: [{
-                message: "Expected return with your callback function.",
+                messageId: "missingReturn",
                 line: 1,
                 column: 19,
                 nodeType: "CallExpression"
@@ -241,7 +240,7 @@ ruleTester.run("callback-return", rule, {
         {
             code: "function a(err) { callback (err); horse(); }",
             errors: [{
-                message: "Expected return with your callback function.",
+                messageId: "missingReturn",
                 line: 1,
                 column: 19,
                 nodeType: "CallExpression"
@@ -250,7 +249,7 @@ ruleTester.run("callback-return", rule, {
         {
             code: "function a(err) { if (err) { callback (err); horse(); return; } }",
             errors: [{
-                message: "Expected return with your callback function.",
+                messageId: "missingReturn",
                 line: 1,
                 column: 30,
                 nodeType: "CallExpression"
@@ -260,7 +259,7 @@ ruleTester.run("callback-return", rule, {
             code: "var a = (err) => { callback (err); callback(); }",
             parserOptions: { ecmaVersion: 6 },
             errors: [{
-                message: "Expected return with your callback function.",
+                messageId: "missingReturn",
                 line: 1,
                 column: 20,
                 nodeType: "CallExpression"
@@ -269,7 +268,7 @@ ruleTester.run("callback-return", rule, {
         {
             code: "function a(err) { if (err) { callback (err); } else if (x) { callback(err); return; } }",
             errors: [{
-                message: "Expected return with your callback function.",
+                messageId: "missingReturn",
                 line: 1,
                 column: 30,
                 nodeType: "CallExpression"
@@ -278,7 +277,7 @@ ruleTester.run("callback-return", rule, {
         {
             code: "function x(err) { if (err) { return callback(); }\nelse if (abc) {\ncallback(); }\nelse {\nreturn callback(); } }",
             errors: [{
-                message: "Expected return with your callback function.",
+                messageId: "missingReturn",
                 line: 3,
                 column: 1,
                 nodeType: "CallExpression"
@@ -289,7 +288,7 @@ ruleTester.run("callback-return", rule, {
             code: "class x { horse() { if (err) { callback(); } callback(); } } ",
             parserOptions: { ecmaVersion: 6 },
             errors: [{
-                message: "Expected return with your callback function.",
+                messageId: "missingReturn",
                 line: 1,
                 column: 32,
                 nodeType: "CallExpression"
@@ -301,12 +300,12 @@ ruleTester.run("callback-return", rule, {
         {
             code: "function x(err) { if (err) { callback() } else { callback() } }",
             errors: [{
-                message: "Expected return with your callback function.",
+                messageId: "missingReturn",
                 line: 1,
                 column: 30,
                 nodeType: "CallExpression"
             }, {
-                message: "Expected return with your callback function.",
+                messageId: "missingReturn",
                 line: 1,
                 column: 50,
                 nodeType: "CallExpression"
@@ -316,7 +315,7 @@ ruleTester.run("callback-return", rule, {
             code: "function x(err) { if (err) return callback(); else callback(); }",
             errors: [
                 {
-                    message: "Expected return with your callback function.",
+                    messageId: "missingReturn",
                     line: 1,
                     column: 52,
                     nodeType: "CallExpression"
@@ -328,7 +327,7 @@ ruleTester.run("callback-return", rule, {
             parserOptions: { ecmaVersion: 6 },
             errors: [
                 {
-                    message: "Expected return with your callback function.",
+                    messageId: "missingReturn",
                     line: 1,
                     column: 18,
                     nodeType: "CallExpression"
@@ -339,7 +338,7 @@ ruleTester.run("callback-return", rule, {
             code: "function b() { switch(x) { case 'horse': callback(); } }",
             errors: [
                 {
-                    message: "Expected return with your callback function.",
+                    messageId: "missingReturn",
                     line: 1,
                     column: 42,
                     nodeType: "CallExpression"
@@ -351,7 +350,7 @@ ruleTester.run("callback-return", rule, {
             options: [["move"]],
             errors: [
                 {
-                    message: "Expected return with your callback function.",
+                    messageId: "missingReturn",
                     line: 1,
                     column: 42,
                     nodeType: "CallExpression"
@@ -365,7 +364,7 @@ ruleTester.run("callback-return", rule, {
             options: [["move"]],
             errors: [
                 {
-                    message: "Expected return with your callback function.",
+                    messageId: "missingReturn",
                     line: 1,
                     column: 33,
                     nodeType: "CallExpression"
@@ -377,7 +376,7 @@ ruleTester.run("callback-return", rule, {
             options: [["move"]],
             errors: [
                 {
-                    message: "Expected return with your callback function.",
+                    messageId: "missingReturn",
                     line: 1,
                     column: 47,
                     nodeType: "CallExpression"
@@ -389,7 +388,7 @@ ruleTester.run("callback-return", rule, {
             options: [["move"]],
             errors: [
                 {
-                    message: "Expected return with your callback function.",
+                    messageId: "missingReturn",
                     line: 1,
                     column: 51,
                     nodeType: "CallExpression"
@@ -401,7 +400,7 @@ ruleTester.run("callback-return", rule, {
             options: [["obj.method"]],
             errors: [
                 {
-                    message: "Expected return with your callback function.",
+                    messageId: "missingReturn",
                     line: 1,
                     column: 30,
                     nodeType: "CallExpression"
@@ -413,7 +412,7 @@ ruleTester.run("callback-return", rule, {
             options: [["obj.prop.method"]],
             errors: [
                 {
-                    message: "Expected return with your callback function.",
+                    messageId: "missingReturn",
                     line: 1,
                     column: 30,
                     nodeType: "CallExpression"
@@ -425,7 +424,7 @@ ruleTester.run("callback-return", rule, {
             options: [["obj.prop.method", "otherObj.prop.method"]],
             errors: [
                 {
-                    message: "Expected return with your callback function.",
+                    messageId: "missingReturn",
                     line: 1,
                     column: 30,
                     nodeType: "CallExpression"
@@ -437,7 +436,7 @@ ruleTester.run("callback-return", rule, {
             options: [["obj.method"]],
             errors: [
                 {
-                    message: "Expected return with your callback function.",
+                    messageId: "missingReturn",
                     line: 1,
                     column: 41,
                     nodeType: "CallExpression"
@@ -449,7 +448,7 @@ ruleTester.run("callback-return", rule, {
             options: [["obj.method"]],
             errors: [
                 {
-                    message: "Expected return with your callback function.",
+                    messageId: "missingReturn",
                     line: 2,
                     column: 1,
                     nodeType: "CallExpression"
@@ -461,7 +460,7 @@ ruleTester.run("callback-return", rule, {
             options: [["obj.method"]],
             errors: [
                 {
-                    message: "Expected return with your callback function.",
+                    messageId: "missingReturn",
                     line: 1,
                     column: 30,
                     nodeType: "CallExpression"
@@ -473,7 +472,7 @@ ruleTester.run("callback-return", rule, {
             options: [["obj.method"]],
             errors: [
                 {
-                    message: "Expected return with your callback function.",
+                    messageId: "missingReturn",
                     line: 1,
                     column: 30,
                     nodeType: "CallExpression"
diff --git a/tests/lib/rules/camelcase.js b/tests/lib/rules/camelcase.js
index 81251ff2c5b..78921bc508b 100644
--- a/tests/lib/rules/camelcase.js
+++ b/tests/lib/rules/camelcase.js
@@ -173,7 +173,8 @@ ruleTester.run("camelcase", rule, {
             code: "first_name = \"Nicholas\"",
             errors: [
                 {
-                    message: "Identifier 'first_name' is not in camel case.",
+                    messageId: "notCamelCase",
+                    data: { name: "first_name" },
                     type: "Identifier"
                 }
             ]
@@ -182,7 +183,8 @@ ruleTester.run("camelcase", rule, {
             code: "__private_first_name = \"Patrick\"",
             errors: [
                 {
-                    message: "Identifier '__private_first_name' is not in camel case.",
+                    messageId: "notCamelCase",
+                    data: { name: "__private_first_name" },
                     type: "Identifier"
                 }
             ]
@@ -191,7 +193,8 @@ ruleTester.run("camelcase", rule, {
             code: "function foo_bar(){}",
             errors: [
                 {
-                    message: "Identifier 'foo_bar' is not in camel case.",
+                    messageId: "notCamelCase",
+                    data: { name: "foo_bar" },
                     type: "Identifier"
                 }
             ]
@@ -200,7 +203,8 @@ ruleTester.run("camelcase", rule, {
             code: "obj.foo_bar = function(){};",
             errors: [
                 {
-                    message: "Identifier 'foo_bar' is not in camel case.",
+                    messageId: "notCamelCase",
+                    data: { name: "foo_bar" },
                     type: "Identifier"
                 }
             ]
@@ -209,7 +213,8 @@ ruleTester.run("camelcase", rule, {
             code: "bar_baz.foo = function(){};",
             errors: [
                 {
-                    message: "Identifier 'bar_baz' is not in camel case.",
+                    messageId: "notCamelCase",
+                    data: { name: "bar_baz" },
                     type: "Identifier"
                 }
             ]
@@ -218,7 +223,8 @@ ruleTester.run("camelcase", rule, {
             code: "[foo_bar.baz]",
             errors: [
                 {
-                    message: "Identifier 'foo_bar' is not in camel case.",
+                    messageId: "notCamelCase",
+                    data: { name: "foo_bar" },
                     type: "Identifier"
                 }
             ]
@@ -227,7 +233,8 @@ ruleTester.run("camelcase", rule, {
             code: "if (foo.bar_baz === boom.bam_pow) { [foo_bar.baz] }",
             errors: [
                 {
-                    message: "Identifier 'foo_bar' is not in camel case.",
+                    messageId: "notCamelCase",
+                    data: { name: "foo_bar" },
                     type: "Identifier"
                 }
             ]
@@ -236,7 +243,8 @@ ruleTester.run("camelcase", rule, {
             code: "foo.bar_baz = boom.bam_pow",
             errors: [
                 {
-                    message: "Identifier 'bar_baz' is not in camel case.",
+                    messageId: "notCamelCase",
+                    data: { name: "bar_baz" },
                     type: "Identifier"
                 }
             ]
@@ -245,7 +253,8 @@ ruleTester.run("camelcase", rule, {
             code: "var foo = { bar_baz: boom.bam_pow }",
             errors: [
                 {
-                    message: "Identifier 'bar_baz' is not in camel case.",
+                    messageId: "notCamelCase",
+                    data: { name: "bar_baz" },
                     type: "Identifier"
                 }
             ]
@@ -254,7 +263,8 @@ ruleTester.run("camelcase", rule, {
             code: "foo.qux.boom_pow = { bar: boom.bam_pow }",
             errors: [
                 {
-                    message: "Identifier 'boom_pow' is not in camel case.",
+                    messageId: "notCamelCase",
+                    data: { name: "boom_pow" },
                     type: "Identifier"
                 }
             ]
@@ -264,7 +274,8 @@ ruleTester.run("camelcase", rule, {
             options: [{ properties: "always" }],
             errors: [
                 {
-                    message: "Identifier 'bar_baz' is not in camel case.",
+                    messageId: "notCamelCase",
+                    data: { name: "bar_baz" },
                     type: "Identifier"
                 }
             ]
@@ -274,7 +285,8 @@ ruleTester.run("camelcase", rule, {
             options: [{ properties: "always" }],
             errors: [
                 {
-                    message: "Identifier 'a_b' is not in camel case.",
+                    messageId: "notCamelCase",
+                    data: { name: "a_b" },
                     type: "Identifier"
                 }
             ]
@@ -284,7 +296,8 @@ ruleTester.run("camelcase", rule, {
             parserOptions: { ecmaVersion: 6 },
             errors: [
                 {
-                    message: "Identifier 'category_id' is not in camel case.",
+                    messageId: "notCamelCase",
+                    data: { name: "category_id" },
                     type: "Identifier"
                 }
             ]
@@ -294,7 +307,8 @@ ruleTester.run("camelcase", rule, {
             parserOptions: { ecmaVersion: 6 },
             errors: [
                 {
-                    message: "Identifier 'category_id' is not in camel case.",
+                    messageId: "notCamelCase",
+                    data: { name: "category_id" },
                     type: "Identifier"
                 }
             ]
@@ -314,7 +328,8 @@ ruleTester.run("camelcase", rule, {
             parserOptions: { ecmaVersion: 6, sourceType: "module" },
             errors: [
                 {
-                    message: "Identifier 'no_camelcased' is not in camel case.",
+                    messageId: "notCamelCase",
+                    data: { name: "no_camelcased" },
                     type: "Identifier"
                 }
             ]
@@ -324,7 +339,8 @@ ruleTester.run("camelcase", rule, {
             parserOptions: { ecmaVersion: 6, sourceType: "module" },
             errors: [
                 {
-                    message: "Identifier 'no_camelcased' is not in camel case.",
+                    messageId: "notCamelCase",
+                    data: { name: "no_camelcased" },
                     type: "Identifier"
                 }
             ]
@@ -334,7 +350,8 @@ ruleTester.run("camelcase", rule, {
             parserOptions: { ecmaVersion: 6, sourceType: "module" },
             errors: [
                 {
-                    message: "Identifier 'no_camelcased' is not in camel case.",
+                    messageId: "notCamelCase",
+                    data: { name: "no_camelcased" },
                     type: "Identifier"
                 }
             ]
@@ -344,7 +361,8 @@ ruleTester.run("camelcase", rule, {
             parserOptions: { ecmaVersion: 6, sourceType: "module" },
             errors: [
                 {
-                    message: "Identifier 'no_camel_cased' is not in camel case.",
+                    messageId: "notCamelCase",
+                    data: { name: "no_camel_cased" },
                     type: "Identifier"
                 }
             ]
@@ -354,7 +372,8 @@ ruleTester.run("camelcase", rule, {
             parserOptions: { ecmaVersion: 6, sourceType: "module" },
             errors: [
                 {
-                    message: "Identifier 'no_camel_cased' is not in camel case.",
+                    messageId: "notCamelCase",
+                    data: { name: "no_camel_cased" },
                     type: "Identifier"
                 }
             ]
@@ -364,7 +383,8 @@ ruleTester.run("camelcase", rule, {
             parserOptions: { ecmaVersion: 6, sourceType: "module" },
             errors: [
                 {
-                    message: "Identifier 'no_camelcased' is not in camel case.",
+                    messageId: "notCamelCase",
+                    data: { name: "no_camelcased" },
                     type: "Identifier"
                 }
             ]
@@ -374,7 +394,8 @@ ruleTester.run("camelcase", rule, {
             parserOptions: { ecmaVersion: 6, sourceType: "module" },
             errors: [
                 {
-                    message: "Identifier 'another_no_camelcased' is not in camel case.",
+                    messageId: "notCamelCase",
+                    data: { name: "another_no_camelcased" },
                     type: "Identifier"
                 }
             ]
@@ -384,7 +405,8 @@ ruleTester.run("camelcase", rule, {
             parserOptions: { ecmaVersion: 6, sourceType: "module" },
             errors: [
                 {
-                    message: "Identifier 'no_camelcased' is not in camel case.",
+                    messageId: "notCamelCase",
+                    data: { name: "no_camelcased" },
                     type: "Identifier"
                 }
             ]
@@ -394,7 +416,8 @@ ruleTester.run("camelcase", rule, {
             parserOptions: { ecmaVersion: 6, sourceType: "module" },
             errors: [
                 {
-                    message: "Identifier 'no_camelcased' is not in camel case.",
+                    messageId: "notCamelCase",
+                    data: { name: "no_camelcased" },
                     type: "Identifier"
                 }
             ]
diff --git a/tests/lib/rules/capitalized-comments.js b/tests/lib/rules/capitalized-comments.js
index ae798a8d5aa..eda2f5234ec 100644
--- a/tests/lib/rules/capitalized-comments.js
+++ b/tests/lib/rules/capitalized-comments.js
@@ -11,14 +11,6 @@
 const rule = require("../../../lib/rules/capitalized-comments"),
     RuleTester = require("../../../lib/testers/rule-tester");
 
-
-//------------------------------------------------------------------------------
-// Helpers
-//------------------------------------------------------------------------------
-
-const ALWAYS_MESSAGE = "Comments should not begin with a lowercase character",
-    NEVER_MESSAGE = "Comments should not begin with an uppercase character";
-
 //------------------------------------------------------------------------------
 // Tests
 //------------------------------------------------------------------------------
@@ -289,7 +281,7 @@ ruleTester.run("capitalized-comments", rule, {
             code: "//lowercase",
             output: "//Lowercase",
             errors: [{
-                message: ALWAYS_MESSAGE,
+                messageId: "unexpectedLowercaseComment",
                 line: 1,
                 column: 1
             }]
@@ -298,7 +290,7 @@ ruleTester.run("capitalized-comments", rule, {
             code: "// lowercase",
             output: "// Lowercase",
             errors: [{
-                message: ALWAYS_MESSAGE,
+                messageId: "unexpectedLowercaseComment",
                 line: 1,
                 column: 1
             }]
@@ -307,7 +299,7 @@ ruleTester.run("capitalized-comments", rule, {
             code: "/*lowercase */",
             output: "/*Lowercase */",
             errors: [{
-                message: ALWAYS_MESSAGE,
+                messageId: "unexpectedLowercaseComment",
                 line: 1,
                 column: 1
             }]
@@ -316,7 +308,7 @@ ruleTester.run("capitalized-comments", rule, {
             code: "/* lowercase */",
             output: "/* Lowercase */",
             errors: [{
-                message: ALWAYS_MESSAGE,
+                messageId: "unexpectedLowercaseComment",
                 line: 1,
                 column: 1
             }]
@@ -325,7 +317,7 @@ ruleTester.run("capitalized-comments", rule, {
             code: "/** lowercase */",
             output: "/** Lowercase */",
             errors: [{
-                message: ALWAYS_MESSAGE,
+                messageId: "unexpectedLowercaseComment",
                 line: 1,
                 column: 1
             }]
@@ -334,7 +326,7 @@ ruleTester.run("capitalized-comments", rule, {
             code: "/*\nlowercase */",
             output: "/*\nLowercase */",
             errors: [{
-                message: ALWAYS_MESSAGE,
+                messageId: "unexpectedLowercaseComment",
                 line: 1,
                 column: 1
             }]
@@ -343,7 +335,7 @@ ruleTester.run("capitalized-comments", rule, {
             code: "/**\nlowercase */",
             output: "/**\nLowercase */",
             errors: [{
-                message: ALWAYS_MESSAGE,
+                messageId: "unexpectedLowercaseComment",
                 line: 1,
                 column: 1
             }]
@@ -352,7 +344,7 @@ ruleTester.run("capitalized-comments", rule, {
             code: "//über",
             output: "//Über",
             errors: [{
-                message: ALWAYS_MESSAGE,
+                messageId: "unexpectedLowercaseComment",
                 line: 1,
                 column: 1
             }]
@@ -361,7 +353,7 @@ ruleTester.run("capitalized-comments", rule, {
             code: "//π",
             output: "//Π",
             errors: [{
-                message: ALWAYS_MESSAGE,
+                messageId: "unexpectedLowercaseComment",
                 line: 1,
                 column: 1
             }]
@@ -370,7 +362,7 @@ ruleTester.run("capitalized-comments", rule, {
             code: "/* lowercase\nSecond line need not be lowercase */",
             output: "/* Lowercase\nSecond line need not be lowercase */",
             errors: [{
-                message: ALWAYS_MESSAGE,
+                messageId: "unexpectedLowercaseComment",
                 line: 1,
                 column: 1
             }]
@@ -382,7 +374,7 @@ ruleTester.run("capitalized-comments", rule, {
             output: "//Lowercase",
             options: ["always"],
             errors: [{
-                message: ALWAYS_MESSAGE,
+                messageId: "unexpectedLowercaseComment",
                 line: 1,
                 column: 1
             }]
@@ -392,7 +384,7 @@ ruleTester.run("capitalized-comments", rule, {
             output: "// Lowercase",
             options: ["always"],
             errors: [{
-                message: ALWAYS_MESSAGE,
+                messageId: "unexpectedLowercaseComment",
                 line: 1,
                 column: 1
             }]
@@ -402,7 +394,7 @@ ruleTester.run("capitalized-comments", rule, {
             output: "/*Lowercase */",
             options: ["always"],
             errors: [{
-                message: ALWAYS_MESSAGE,
+                messageId: "unexpectedLowercaseComment",
                 line: 1,
                 column: 1
             }]
@@ -412,7 +404,7 @@ ruleTester.run("capitalized-comments", rule, {
             output: "/* Lowercase */",
             options: ["always"],
             errors: [{
-                message: ALWAYS_MESSAGE,
+                messageId: "unexpectedLowercaseComment",
                 line: 1,
                 column: 1
             }]
@@ -422,7 +414,7 @@ ruleTester.run("capitalized-comments", rule, {
             output: "/** Lowercase */",
             options: ["always"],
             errors: [{
-                message: ALWAYS_MESSAGE,
+                messageId: "unexpectedLowercaseComment",
                 line: 1,
                 column: 1
             }]
@@ -432,7 +424,7 @@ ruleTester.run("capitalized-comments", rule, {
             output: "/**\nLowercase */",
             options: ["always"],
             errors: [{
-                message: ALWAYS_MESSAGE,
+                messageId: "unexpectedLowercaseComment",
                 line: 1,
                 column: 1
             }]
@@ -442,7 +434,7 @@ ruleTester.run("capitalized-comments", rule, {
             output: "//Über",
             options: ["always"],
             errors: [{
-                message: ALWAYS_MESSAGE,
+                messageId: "unexpectedLowercaseComment",
                 line: 1,
                 column: 1
             }]
@@ -452,7 +444,7 @@ ruleTester.run("capitalized-comments", rule, {
             output: "//Π",
             options: ["always"],
             errors: [{
-                message: ALWAYS_MESSAGE,
+                messageId: "unexpectedLowercaseComment",
                 line: 1,
                 column: 1
             }]
@@ -462,7 +454,7 @@ ruleTester.run("capitalized-comments", rule, {
             output: "/* Lowercase\nSecond line need not be lowercase */",
             options: ["always"],
             errors: [{
-                message: ALWAYS_MESSAGE,
+                messageId: "unexpectedLowercaseComment",
                 line: 1,
                 column: 1
             }]
@@ -474,7 +466,7 @@ ruleTester.run("capitalized-comments", rule, {
             output: "//uppercase",
             options: ["never"],
             errors: [{
-                message: NEVER_MESSAGE,
+                messageId: "unexpectedUppercaseComment",
                 line: 1,
                 column: 1
             }]
@@ -484,7 +476,7 @@ ruleTester.run("capitalized-comments", rule, {
             output: "// uppercase",
             options: ["never"],
             errors: [{
-                message: NEVER_MESSAGE,
+                messageId: "unexpectedUppercaseComment",
                 line: 1,
                 column: 1
             }]
@@ -494,7 +486,7 @@ ruleTester.run("capitalized-comments", rule, {
             output: "/*uppercase */",
             options: ["never"],
             errors: [{
-                message: NEVER_MESSAGE,
+                messageId: "unexpectedUppercaseComment",
                 line: 1,
                 column: 1
             }]
@@ -504,7 +496,7 @@ ruleTester.run("capitalized-comments", rule, {
             output: "/* uppercase */",
             options: ["never"],
             errors: [{
-                message: NEVER_MESSAGE,
+                messageId: "unexpectedUppercaseComment",
                 line: 1,
                 column: 1
             }]
@@ -514,7 +506,7 @@ ruleTester.run("capitalized-comments", rule, {
             output: "/*\nuppercase */",
             options: ["never"],
             errors: [{
-                message: NEVER_MESSAGE,
+                messageId: "unexpectedUppercaseComment",
                 line: 1,
                 column: 1
             }]
@@ -524,7 +516,7 @@ ruleTester.run("capitalized-comments", rule, {
             output: "//über",
             options: ["never"],
             errors: [{
-                message: NEVER_MESSAGE,
+                messageId: "unexpectedUppercaseComment",
                 line: 1,
                 column: 1
             }]
@@ -534,7 +526,7 @@ ruleTester.run("capitalized-comments", rule, {
             output: "//π",
             options: ["never"],
             errors: [{
-                message: NEVER_MESSAGE,
+                messageId: "unexpectedUppercaseComment",
                 line: 1,
                 column: 1
             }]
@@ -544,7 +536,7 @@ ruleTester.run("capitalized-comments", rule, {
             output: "/* uppercase\nsecond line need not be uppercase */",
             options: ["never"],
             errors: [{
-                message: NEVER_MESSAGE,
+                messageId: "unexpectedUppercaseComment",
                 line: 1,
                 column: 1
             }]
@@ -556,7 +548,7 @@ ruleTester.run("capitalized-comments", rule, {
             output: "//* Jscs: enable",
             options: ["always"],
             errors: [{
-                message: ALWAYS_MESSAGE,
+                messageId: "unexpectedLowercaseComment",
                 line: 1,
                 column: 1
             }]
@@ -566,7 +558,7 @@ ruleTester.run("capitalized-comments", rule, {
             output: "//* Jscs:disable",
             options: ["always"],
             errors: [{
-                message: ALWAYS_MESSAGE,
+                messageId: "unexpectedLowercaseComment",
                 line: 1,
                 column: 1
             }]
@@ -576,7 +568,7 @@ ruleTester.run("capitalized-comments", rule, {
             output: "//* Eslint-disable-line",
             options: ["always"],
             errors: [{
-                message: ALWAYS_MESSAGE,
+                messageId: "unexpectedLowercaseComment",
                 line: 1,
                 column: 1
             }]
@@ -586,7 +578,7 @@ ruleTester.run("capitalized-comments", rule, {
             output: "//* Eslint-disable-next-line",
             options: ["always"],
             errors: [{
-                message: ALWAYS_MESSAGE,
+                messageId: "unexpectedLowercaseComment",
                 line: 1,
                 column: 1
             }]
@@ -596,7 +588,7 @@ ruleTester.run("capitalized-comments", rule, {
             output: "/*\n * Eslint semi:off */",
             options: ["always"],
             errors: [{
-                message: ALWAYS_MESSAGE,
+                messageId: "unexpectedLowercaseComment",
                 line: 1,
                 column: 1
             }]
@@ -606,7 +598,7 @@ ruleTester.run("capitalized-comments", rule, {
             output: "/*\n * Eslint-env node */",
             options: ["always"],
             errors: [{
-                message: ALWAYS_MESSAGE,
+                messageId: "unexpectedLowercaseComment",
                 line: 1,
                 column: 1
             }]
@@ -616,7 +608,7 @@ ruleTester.run("capitalized-comments", rule, {
             output: "/*\n *  Istanbul ignore next */",
             options: ["always"],
             errors: [{
-                message: ALWAYS_MESSAGE,
+                messageId: "unexpectedLowercaseComment",
                 line: 1,
                 column: 1
             }]
@@ -626,7 +618,7 @@ ruleTester.run("capitalized-comments", rule, {
             output: "/*\n *  Jshint asi:true */",
             options: ["always"],
             errors: [{
-                message: ALWAYS_MESSAGE,
+                messageId: "unexpectedLowercaseComment",
                 line: 1,
                 column: 1
             }]
@@ -636,7 +628,7 @@ ruleTester.run("capitalized-comments", rule, {
             output: "/*\n *  Jscs: enable */",
             options: ["always"],
             errors: [{
-                message: ALWAYS_MESSAGE,
+                messageId: "unexpectedLowercaseComment",
                 line: 1,
                 column: 1
             }]
@@ -646,7 +638,7 @@ ruleTester.run("capitalized-comments", rule, {
             output: "/*\n *  Global var1, var2 */",
             options: ["always"],
             errors: [{
-                message: ALWAYS_MESSAGE,
+                messageId: "unexpectedLowercaseComment",
                 line: 1,
                 column: 1
             }]
@@ -656,7 +648,7 @@ ruleTester.run("capitalized-comments", rule, {
             output: "/*\n *  Global var1:true, var2 */",
             options: ["always"],
             errors: [{
-                message: ALWAYS_MESSAGE,
+                messageId: "unexpectedLowercaseComment",
                 line: 1,
                 column: 1
             }]
@@ -666,7 +658,7 @@ ruleTester.run("capitalized-comments", rule, {
             output: "/*\n *  Globals var1, var2 */",
             options: ["always"],
             errors: [{
-                message: ALWAYS_MESSAGE,
+                messageId: "unexpectedLowercaseComment",
                 line: 1,
                 column: 1
             }]
@@ -676,7 +668,7 @@ ruleTester.run("capitalized-comments", rule, {
             output: "/*\n *  Globals var1:true, var2 */",
             options: ["always"],
             errors: [{
-                message: ALWAYS_MESSAGE,
+                messageId: "unexpectedLowercaseComment",
                 line: 1,
                 column: 1
             }]
@@ -686,7 +678,7 @@ ruleTester.run("capitalized-comments", rule, {
             output: "/*\n *  Exported myVar */",
             options: ["always"],
             errors: [{
-                message: ALWAYS_MESSAGE,
+                messageId: "unexpectedLowercaseComment",
                 line: 1,
                 column: 1
             }]
@@ -698,7 +690,7 @@ ruleTester.run("capitalized-comments", rule, {
             output: "foo(/* Invalid */a);",
             options: ["always"],
             errors: [{
-                message: ALWAYS_MESSAGE,
+                messageId: "unexpectedLowercaseComment",
                 line: 1,
                 column: 5
             }]
@@ -708,7 +700,7 @@ ruleTester.run("capitalized-comments", rule, {
             output: "foo(/* Invalid */a);",
             options: ["always", { ignoreInlineComments: false }],
             errors: [{
-                message: ALWAYS_MESSAGE,
+                messageId: "unexpectedLowercaseComment",
                 line: 1,
                 column: 5
             }]
@@ -720,7 +712,7 @@ ruleTester.run("capitalized-comments", rule, {
             output: "foo(a, // Not an inline comment\nb);",
             options: ["always", { ignoreInlineComments: true }],
             errors: [{
-                message: ALWAYS_MESSAGE,
+                messageId: "unexpectedLowercaseComment",
                 line: 1,
                 column: 8
             }]
@@ -730,7 +722,7 @@ ruleTester.run("capitalized-comments", rule, {
             output: "foo(a, /* Not an inline comment */\nb);",
             options: ["always", { ignoreInlineComments: true }],
             errors: [{
-                message: ALWAYS_MESSAGE,
+                messageId: "unexpectedLowercaseComment",
                 line: 1,
                 column: 8
             }]
@@ -740,7 +732,7 @@ ruleTester.run("capitalized-comments", rule, {
             output: "foo(a,\n/* Not an inline comment */b);",
             options: ["always", { ignoreInlineComments: true }],
             errors: [{
-                message: ALWAYS_MESSAGE,
+                messageId: "unexpectedLowercaseComment",
                 line: 2,
                 column: 1
             }]
@@ -750,7 +742,7 @@ ruleTester.run("capitalized-comments", rule, {
             output: "foo(a,\n/* Not an inline comment */\nb);",
             options: ["always", { ignoreInlineComments: true }],
             errors: [{
-                message: ALWAYS_MESSAGE,
+                messageId: "unexpectedLowercaseComment",
                 line: 2,
                 column: 1
             }]
@@ -760,7 +752,7 @@ ruleTester.run("capitalized-comments", rule, {
             output: "foo(a, // not an inline comment\nb);",
             options: ["never", { ignoreInlineComments: true }],
             errors: [{
-                message: NEVER_MESSAGE,
+                messageId: "unexpectedUppercaseComment",
                 line: 1,
                 column: 8
             }]
@@ -770,7 +762,7 @@ ruleTester.run("capitalized-comments", rule, {
             output: "foo(a, /* not an inline comment */\nb);",
             options: ["never", { ignoreInlineComments: true }],
             errors: [{
-                message: NEVER_MESSAGE,
+                messageId: "unexpectedUppercaseComment",
                 line: 1,
                 column: 8
             }]
@@ -780,7 +772,7 @@ ruleTester.run("capitalized-comments", rule, {
             output: "foo(a,\n/* not an inline comment */b);",
             options: ["never", { ignoreInlineComments: true }],
             errors: [{
-                message: NEVER_MESSAGE,
+                messageId: "unexpectedUppercaseComment",
                 line: 2,
                 column: 1
             }]
@@ -790,7 +782,7 @@ ruleTester.run("capitalized-comments", rule, {
             output: "foo(a,\n/* not an inline comment */\nb);",
             options: ["never", { ignoreInlineComments: true }],
             errors: [{
-                message: NEVER_MESSAGE,
+                messageId: "unexpectedUppercaseComment",
                 line: 2,
                 column: 1
             }]
@@ -802,7 +794,7 @@ ruleTester.run("capitalized-comments", rule, {
             output: "// Not matching",
             options: ["always", { ignorePattern: "ignored?" }],
             errors: [{
-                message: ALWAYS_MESSAGE,
+                messageId: "unexpectedLowercaseComment",
                 line: 1,
                 column: 1
             }]
@@ -812,7 +804,7 @@ ruleTester.run("capitalized-comments", rule, {
             output: "// not matching",
             options: ["never", { ignorePattern: "ignored?" }],
             errors: [{
-                message: NEVER_MESSAGE,
+                messageId: "unexpectedUppercaseComment",
                 line: 1,
                 column: 1
             }]
@@ -834,7 +826,7 @@ ruleTester.run("capitalized-comments", rule, {
             ].join("\n"),
             options: ["always", { ignoreConsecutiveComments: true }],
             errors: [{
-                message: ALWAYS_MESSAGE,
+                messageId: "unexpectedLowercaseComment",
                 line: 4,
                 column: 1
             }]
@@ -852,7 +844,7 @@ ruleTester.run("capitalized-comments", rule, {
             ].join("\n"),
             options: ["always", { ignoreConsecutiveComments: true }],
             errors: [{
-                message: ALWAYS_MESSAGE,
+                messageId: "unexpectedLowercaseComment",
                 line: 1,
                 column: 1
             }]
@@ -868,7 +860,7 @@ ruleTester.run("capitalized-comments", rule, {
             ].join("\n"),
             options: ["never", { ignoreConsecutiveComments: true }],
             errors: [{
-                message: NEVER_MESSAGE,
+                messageId: "unexpectedUppercaseComment",
                 line: 1,
                 column: 1
             }]
@@ -886,7 +878,7 @@ ruleTester.run("capitalized-comments", rule, {
             ].join("\n"),
             options: ["always", { ignoreConsecutiveComments: false }],
             errors: [{
-                message: ALWAYS_MESSAGE,
+                messageId: "unexpectedLowercaseComment",
                 line: 2,
                 column: 1
             }]
@@ -898,7 +890,7 @@ ruleTester.run("capitalized-comments", rule, {
             output: "// Should fail. https://github.com",
             options: ["always"],
             errors: [{
-                message: ALWAYS_MESSAGE,
+                messageId: "unexpectedLowercaseComment",
                 line: 1,
                 column: 1
             }]
@@ -908,7 +900,7 @@ ruleTester.run("capitalized-comments", rule, {
             output: "// should fail. https://github.com",
             options: ["never"],
             errors: [{
-                message: NEVER_MESSAGE,
+                messageId: "unexpectedUppercaseComment",
                 line: 1,
                 column: 1
             }]
diff --git a/tests/lib/rules/class-methods-use-this.js b/tests/lib/rules/class-methods-use-this.js
index fbddd027013..369f04a64f9 100644
--- a/tests/lib/rules/class-methods-use-this.js
+++ b/tests/lib/rules/class-methods-use-this.js
@@ -37,49 +37,49 @@ ruleTester.run("class-methods-use-this", rule, {
             code: "class A { foo() {} }",
             parserOptions: { ecmaVersion: 6 },
             errors: [
-                { type: "FunctionExpression", line: 1, column: 14, message: "Expected 'this' to be used by class method 'foo'." }
+                { type: "FunctionExpression", line: 1, column: 14, messageId: "missingThis", data: { name: "foo" } }
             ]
         },
         {
             code: "class A { foo() {/**this**/} }",
             parserOptions: { ecmaVersion: 6 },
             errors: [
-                { type: "FunctionExpression", line: 1, column: 14, message: "Expected 'this' to be used by class method 'foo'." }
+                { type: "FunctionExpression", line: 1, column: 14, messageId: "missingThis", data: { name: "foo" } }
             ]
         },
         {
             code: "class A { foo() {var a = function () {this};} }",
             parserOptions: { ecmaVersion: 6 },
             errors: [
-                { type: "FunctionExpression", line: 1, column: 14, message: "Expected 'this' to be used by class method 'foo'." }
+                { type: "FunctionExpression", line: 1, column: 14, messageId: "missingThis", data: { name: "foo" } }
             ]
         },
         {
             code: "class A { foo() {var a = function () {var b = function(){this}};} }",
             parserOptions: { ecmaVersion: 6 },
             errors: [
-                { type: "FunctionExpression", line: 1, column: 14, message: "Expected 'this' to be used by class method 'foo'." }
+                { type: "FunctionExpression", line: 1, column: 14, messageId: "missingThis", data: { name: "foo" } }
             ]
         },
         {
             code: "class A { foo() {window.this} }",
             parserOptions: { ecmaVersion: 6 },
             errors: [
-                { type: "FunctionExpression", line: 1, column: 14, message: "Expected 'this' to be used by class method 'foo'." }
+                { type: "FunctionExpression", line: 1, column: 14, messageId: "missingThis", data: { name: "foo" } }
             ]
         },
         {
             code: "class A { foo() {that.this = 'this';} }",
             parserOptions: { ecmaVersion: 6 },
             errors: [
-                { type: "FunctionExpression", line: 1, column: 14, message: "Expected 'this' to be used by class method 'foo'." }
+                { type: "FunctionExpression", line: 1, column: 14, messageId: "missingThis", data: { name: "foo" } }
             ]
         },
         {
             code: "class A { foo() { () => undefined; } }",
             parserOptions: { ecmaVersion: 6 },
             errors: [
-                { type: "FunctionExpression", line: 1, column: 14, message: "Expected 'this' to be used by class method 'foo'." }
+                { type: "FunctionExpression", line: 1, column: 14, messageId: "missingThis", data: { name: "foo" } }
             ]
         },
         {
@@ -87,7 +87,7 @@ ruleTester.run("class-methods-use-this", rule, {
             options: [{ exceptMethods: ["bar"] }],
             parserOptions: { ecmaVersion: 6 },
             errors: [
-                { type: "FunctionExpression", line: 1, column: 14, message: "Expected 'this' to be used by class method 'foo'." }
+                { type: "FunctionExpression", line: 1, column: 14, messageId: "missingThis", data: { name: "foo" } }
             ]
         },
         {
@@ -95,7 +95,7 @@ ruleTester.run("class-methods-use-this", rule, {
             options: [{ exceptMethods: ["foo"] }],
             parserOptions: { ecmaVersion: 6 },
             errors: [
-                { type: "FunctionExpression", line: 1, column: 34, message: "Expected 'this' to be used by class method 'hasOwnProperty'." }
+                { type: "FunctionExpression", line: 1, column: 34, messageId: "missingThis", data: { name: "hasOwnProperty" } }
             ]
         }
     ]
diff --git a/tests/lib/rules/comma-dangle.js b/tests/lib/rules/comma-dangle.js
index 1a4f80a7725..29027e9496a 100644
--- a/tests/lib/rules/comma-dangle.js
+++ b/tests/lib/rules/comma-dangle.js
@@ -410,7 +410,7 @@ ruleTester.run("comma-dangle", rule, {
             output: "var foo = { bar: 'baz' }",
             errors: [
                 {
-                    message: "Unexpected trailing comma.",
+                    messageId: "unexpected",
                     type: "Property",
                     line: 1,
                     column: 23
@@ -422,7 +422,7 @@ ruleTester.run("comma-dangle", rule, {
             output: "var foo = {\nbar: 'baz'\n}",
             errors: [
                 {
-                    message: "Unexpected trailing comma.",
+                    messageId: "unexpected",
                     type: "Property",
                     line: 2,
                     column: 11
@@ -434,7 +434,7 @@ ruleTester.run("comma-dangle", rule, {
             output: "foo({ bar: 'baz', qux: 'quux' });",
             errors: [
                 {
-                    message: "Unexpected trailing comma.",
+                    messageId: "unexpected",
                     type: "Property",
                     line: 1,
                     column: 30
@@ -446,7 +446,7 @@ ruleTester.run("comma-dangle", rule, {
             output: "foo({\nbar: 'baz',\nqux: 'quux'\n});",
             errors: [
                 {
-                    message: "Unexpected trailing comma.",
+                    messageId: "unexpected",
                     type: "Property",
                     line: 3,
                     column: 12
@@ -458,7 +458,7 @@ ruleTester.run("comma-dangle", rule, {
             output: "var foo = [ 'baz' ]",
             errors: [
                 {
-                    message: "Unexpected trailing comma.",
+                    messageId: "unexpected",
                     type: "Literal",
                     line: 1,
                     column: 18
@@ -470,7 +470,7 @@ ruleTester.run("comma-dangle", rule, {
             output: "var foo = [ 'baz'\n]",
             errors: [
                 {
-                    message: "Unexpected trailing comma.",
+                    messageId: "unexpected",
                     type: "Literal",
                     line: 1,
                     column: 18
@@ -482,7 +482,7 @@ ruleTester.run("comma-dangle", rule, {
             output: "var foo = { bar: 'bar'\n\n }",
             errors: [
                 {
-                    message: "Unexpected trailing comma.",
+                    messageId: "unexpected",
                     type: "Property",
                     line: 3,
                     column: 1
@@ -497,7 +497,7 @@ ruleTester.run("comma-dangle", rule, {
             options: ["never"],
             errors: [
                 {
-                    message: "Unexpected trailing comma.",
+                    messageId: "unexpected",
                     type: "Property",
                     line: 1,
                     column: 23
@@ -510,7 +510,7 @@ ruleTester.run("comma-dangle", rule, {
             options: ["only-multiline"],
             errors: [
                 {
-                    message: "Unexpected trailing comma.",
+                    messageId: "unexpected",
                     type: "Property",
                     line: 1,
                     column: 23
@@ -523,7 +523,7 @@ ruleTester.run("comma-dangle", rule, {
             options: ["never"],
             errors: [
                 {
-                    message: "Unexpected trailing comma.",
+                    messageId: "unexpected",
                     type: "Property",
                     line: 2,
                     column: 11
@@ -536,7 +536,7 @@ ruleTester.run("comma-dangle", rule, {
             options: ["never"],
             errors: [
                 {
-                    message: "Unexpected trailing comma.",
+                    messageId: "unexpected",
                     type: "Property",
                     line: 1,
                     column: 30
@@ -549,7 +549,7 @@ ruleTester.run("comma-dangle", rule, {
             options: ["only-multiline"],
             errors: [
                 {
-                    message: "Unexpected trailing comma.",
+                    messageId: "unexpected",
                     type: "Property",
                     line: 1,
                     column: 30
@@ -563,7 +563,7 @@ ruleTester.run("comma-dangle", rule, {
             options: ["always"],
             errors: [
                 {
-                    message: "Missing trailing comma.",
+                    messageId: "missing",
                     type: "Property",
                     line: 1,
                     column: 23
@@ -576,7 +576,7 @@ ruleTester.run("comma-dangle", rule, {
             options: ["always"],
             errors: [
                 {
-                    message: "Missing trailing comma.",
+                    messageId: "missing",
                     type: "Property",
                     line: 2,
                     column: 11
@@ -589,7 +589,7 @@ ruleTester.run("comma-dangle", rule, {
             options: ["always"],
             errors: [
                 {
-                    message: "Missing trailing comma.",
+                    messageId: "missing",
                     type: "Property",
                     line: 1,
                     column: 30
@@ -602,7 +602,7 @@ ruleTester.run("comma-dangle", rule, {
             options: ["always"],
             errors: [
                 {
-                    message: "Missing trailing comma.",
+                    messageId: "missing",
                     type: "Property",
                     line: 3,
                     column: 12
@@ -615,7 +615,7 @@ ruleTester.run("comma-dangle", rule, {
             options: ["always"],
             errors: [
                 {
-                    message: "Missing trailing comma.",
+                    messageId: "missing",
                     type: "Literal",
                     line: 1,
                     column: 18
@@ -628,7 +628,7 @@ ruleTester.run("comma-dangle", rule, {
             options: ["always"],
             errors: [
                 {
-                    message: "Missing trailing comma.",
+                    messageId: "missing",
                     type: "Literal",
                     line: 1,
                     column: 18
@@ -641,7 +641,7 @@ ruleTester.run("comma-dangle", rule, {
             options: ["always"],
             errors: [
                 {
-                    message: "Missing trailing comma.",
+                    messageId: "missing",
                     type: "Property",
                     line: 3,
                     column: 6
@@ -655,7 +655,7 @@ ruleTester.run("comma-dangle", rule, {
             options: ["always-multiline"],
             errors: [
                 {
-                    message: "Missing trailing comma.",
+                    messageId: "missing",
                     type: "Property",
                     line: 2,
                     column: 11
@@ -680,7 +680,7 @@ ruleTester.run("comma-dangle", rule, {
             options: ["always"],
             errors: [
                 {
-                    message: "Missing trailing comma.",
+                    messageId: "missing",
                     type: "Identifier",
                     line: 5,
                     column: 4
@@ -705,7 +705,7 @@ ruleTester.run("comma-dangle", rule, {
             options: ["always"],
             errors: [
                 {
-                    message: "Missing trailing comma.",
+                    messageId: "missing",
                     type: "Property",
                     line: 5,
                     column: 4
@@ -732,7 +732,7 @@ ruleTester.run("comma-dangle", rule, {
             options: ["always"],
             errors: [
                 {
-                    message: "Missing trailing comma.",
+                    messageId: "missing",
                     type: "ConditionalExpression",
                     line: 5,
                     column: 4
@@ -745,7 +745,7 @@ ruleTester.run("comma-dangle", rule, {
             options: ["always-multiline"],
             errors: [
                 {
-                    message: "Unexpected trailing comma.",
+                    messageId: "unexpected",
                     type: "Property",
                     line: 1,
                     column: 23
@@ -758,7 +758,7 @@ ruleTester.run("comma-dangle", rule, {
             options: ["always-multiline"],
             errors: [
                 {
-                    message: "Missing trailing comma.",
+                    messageId: "missing",
                     type: "Property",
                     line: 3,
                     column: 12
@@ -771,7 +771,7 @@ ruleTester.run("comma-dangle", rule, {
             options: ["always-multiline"],
             errors: [
                 {
-                    message: "Unexpected trailing comma.",
+                    messageId: "unexpected",
                     type: "Property",
                     line: 1,
                     column: 30
@@ -784,7 +784,7 @@ ruleTester.run("comma-dangle", rule, {
             options: ["always-multiline"],
             errors: [
                 {
-                    message: "Missing trailing comma.",
+                    messageId: "missing",
                     type: "Literal",
                     line: 2,
                     column: 6
@@ -797,7 +797,7 @@ ruleTester.run("comma-dangle", rule, {
             options: ["always-multiline"],
             errors: [
                 {
-                    message: "Unexpected trailing comma.",
+                    messageId: "unexpected",
                     type: "Literal",
                     line: 1,
                     column: 17
@@ -810,7 +810,7 @@ ruleTester.run("comma-dangle", rule, {
             options: ["only-multiline"],
             errors: [
                 {
-                    message: "Unexpected trailing comma.",
+                    messageId: "unexpected",
                     type: "Literal",
                     line: 1,
                     column: 17
@@ -823,7 +823,7 @@ ruleTester.run("comma-dangle", rule, {
             options: ["always-multiline"],
             errors: [
                 {
-                    message: "Unexpected trailing comma.",
+                    messageId: "unexpected",
                     type: "Property",
                     line: 3,
                     column: 2
@@ -836,7 +836,7 @@ ruleTester.run("comma-dangle", rule, {
             options: ["always-multiline"],
             errors: [
                 {
-                    message: "Unexpected trailing comma.",
+                    messageId: "unexpected",
                     type: "Property",
                     line: 2,
                     column: 11
@@ -849,7 +849,7 @@ ruleTester.run("comma-dangle", rule, {
             options: ["only-multiline"],
             errors: [
                 {
-                    message: "Unexpected trailing comma.",
+                    messageId: "unexpected",
                     type: "Property",
                     line: 2,
                     column: 11
@@ -862,7 +862,7 @@ ruleTester.run("comma-dangle", rule, {
             options: ["always-multiline"],
             errors: [
                 {
-                    message: "Unexpected trailing comma.",
+                    messageId: "unexpected",
                     type: "ObjectExpression",
                     line: 6,
                     column: 2
@@ -876,7 +876,7 @@ ruleTester.run("comma-dangle", rule, {
             parserOptions: { ecmaVersion: 6 },
             errors: [
                 {
-                    message: "Unexpected trailing comma.",
+                    messageId: "unexpected",
                     type: "Property",
                     line: 1,
                     column: 11
@@ -890,7 +890,7 @@ ruleTester.run("comma-dangle", rule, {
             parserOptions: { ecmaVersion: 6 },
             errors: [
                 {
-                    message: "Unexpected trailing comma.",
+                    messageId: "unexpected",
                     type: "Property",
                     line: 1,
                     column: 11
@@ -904,7 +904,7 @@ ruleTester.run("comma-dangle", rule, {
             parserOptions: { ecmaVersion: 6 },
             errors: [
                 {
-                    message: "Unexpected trailing comma.",
+                    messageId: "unexpected",
                     type: "Identifier",
                     line: 1,
                     column: 11
@@ -918,7 +918,7 @@ ruleTester.run("comma-dangle", rule, {
             parserOptions: { ecmaVersion: 6 },
             errors: [
                 {
-                    message: "Unexpected trailing comma.",
+                    messageId: "unexpected",
                     type: "Identifier",
                     line: 1,
                     column: 11
@@ -931,7 +931,7 @@ ruleTester.run("comma-dangle", rule, {
             options: ["never"],
             errors: [
                 {
-                    message: "Unexpected trailing comma.",
+                    messageId: "unexpected",
                     type: "Literal",
                     line: 1,
                     column: 5
@@ -944,7 +944,7 @@ ruleTester.run("comma-dangle", rule, {
             options: ["only-multiline"],
             errors: [
                 {
-                    message: "Unexpected trailing comma.",
+                    messageId: "unexpected",
                     type: "Literal",
                     line: 1,
                     column: 5
@@ -957,7 +957,7 @@ ruleTester.run("comma-dangle", rule, {
             options: ["never"],
             errors: [
                 {
-                    message: "Unexpected trailing comma.",
+                    messageId: "unexpected",
                     type: "Property",
                     line: 1,
                     column: 19
@@ -970,7 +970,7 @@ ruleTester.run("comma-dangle", rule, {
             options: ["only-multiline"],
             errors: [
                 {
-                    message: "Unexpected trailing comma.",
+                    messageId: "unexpected",
                     type: "Property",
                     line: 1,
                     column: 19
@@ -984,91 +984,91 @@ ruleTester.run("comma-dangle", rule, {
             output: "import {foo,} from 'foo';",
             options: ["always"],
             parserOptions: { sourceType: "module" },
-            errors: [{ message: "Missing trailing comma.", type: "ImportSpecifier" }]
+            errors: [{ messageId: "missing", type: "ImportSpecifier" }]
         },
         {
             code: "import foo, {abc} from 'foo';",
             output: "import foo, {abc,} from 'foo';",
             options: ["always"],
             parserOptions: { sourceType: "module" },
-            errors: [{ message: "Missing trailing comma.", type: "ImportSpecifier" }]
+            errors: [{ messageId: "missing", type: "ImportSpecifier" }]
         },
         {
             code: "export {foo} from 'foo';",
             output: "export {foo,} from 'foo';",
             options: ["always"],
             parserOptions: { sourceType: "module" },
-            errors: [{ message: "Missing trailing comma.", type: "ExportSpecifier" }]
+            errors: [{ messageId: "missing", type: "ExportSpecifier" }]
         },
         {
             code: "import {foo,} from 'foo';",
             output: "import {foo} from 'foo';",
             options: ["never"],
             parserOptions: { sourceType: "module" },
-            errors: [{ message: "Unexpected trailing comma.", type: "ImportSpecifier" }]
+            errors: [{ messageId: "unexpected", type: "ImportSpecifier" }]
         },
         {
             code: "import {foo,} from 'foo';",
             output: "import {foo} from 'foo';",
             options: ["only-multiline"],
             parserOptions: { sourceType: "module" },
-            errors: [{ message: "Unexpected trailing comma.", type: "ImportSpecifier" }]
+            errors: [{ messageId: "unexpected", type: "ImportSpecifier" }]
         },
         {
             code: "import foo, {abc,} from 'foo';",
             output: "import foo, {abc} from 'foo';",
             options: ["never"],
             parserOptions: { sourceType: "module" },
-            errors: [{ message: "Unexpected trailing comma.", type: "ImportSpecifier" }]
+            errors: [{ messageId: "unexpected", type: "ImportSpecifier" }]
         },
         {
             code: "import foo, {abc,} from 'foo';",
             output: "import foo, {abc} from 'foo';",
             options: ["only-multiline"],
             parserOptions: { sourceType: "module" },
-            errors: [{ message: "Unexpected trailing comma.", type: "ImportSpecifier" }]
+            errors: [{ messageId: "unexpected", type: "ImportSpecifier" }]
         },
         {
             code: "export {foo,} from 'foo';",
             output: "export {foo} from 'foo';",
             options: ["never"],
             parserOptions: { sourceType: "module" },
-            errors: [{ message: "Unexpected trailing comma.", type: "ExportSpecifier" }]
+            errors: [{ messageId: "unexpected", type: "ExportSpecifier" }]
         },
         {
             code: "export {foo,} from 'foo';",
             output: "export {foo} from 'foo';",
             options: ["only-multiline"],
             parserOptions: { sourceType: "module" },
-            errors: [{ message: "Unexpected trailing comma.", type: "ExportSpecifier" }]
+            errors: [{ messageId: "unexpected", type: "ExportSpecifier" }]
         },
         {
             code: "import {foo,} from 'foo';",
             output: "import {foo} from 'foo';",
             options: ["always-multiline"],
             parserOptions: { sourceType: "module" },
-            errors: [{ message: "Unexpected trailing comma.", type: "ImportSpecifier" }]
+            errors: [{ messageId: "unexpected", type: "ImportSpecifier" }]
         },
         {
             code: "export {foo,} from 'foo';",
             output: "export {foo} from 'foo';",
             options: ["always-multiline"],
             parserOptions: { sourceType: "module" },
-            errors: [{ message: "Unexpected trailing comma.", type: "ExportSpecifier" }]
+            errors: [{ messageId: "unexpected", type: "ExportSpecifier" }]
         },
         {
             code: "import {\n  foo\n} from 'foo';",
             output: "import {\n  foo,\n} from 'foo';",
             options: ["always-multiline"],
             parserOptions: { sourceType: "module" },
-            errors: [{ message: "Missing trailing comma.", type: "ImportSpecifier" }]
+            errors: [{ messageId: "missing", type: "ImportSpecifier" }]
         },
         {
             code: "export {\n  foo\n} from 'foo';",
             output: "export {\n  foo,\n} from 'foo';",
             options: ["always-multiline"],
             parserOptions: { sourceType: "module" },
-            errors: [{ message: "Missing trailing comma.", type: "ExportSpecifier" }]
+            errors: [{ messageId: "missing", type: "ExportSpecifier" }]
         },
 
         // https://github.com/eslint/eslint/issues/6233
@@ -1076,19 +1076,19 @@ ruleTester.run("comma-dangle", rule, {
             code: "var foo = {a: (1)}",
             output: "var foo = {a: (1),}",
             options: ["always"],
-            errors: [{ message: "Missing trailing comma.", type: "Property" }]
+            errors: [{ messageId: "missing", type: "Property" }]
         },
         {
             code: "var foo = [(1)]",
             output: "var foo = [(1),]",
             options: ["always"],
-            errors: [{ message: "Missing trailing comma.", type: "Literal" }]
+            errors: [{ messageId: "missing", type: "Literal" }]
         },
         {
             code: "var foo = [\n1,\n(2)\n]",
             output: "var foo = [\n1,\n(2),\n]",
             options: ["always-multiline"],
-            errors: [{ message: "Missing trailing comma.", type: "Literal" }]
+            errors: [{ messageId: "missing", type: "Literal" }]
         },
 
         // trailing commas in functions
@@ -1097,56 +1097,56 @@ ruleTester.run("comma-dangle", rule, {
             output: "function foo(a) {}",
             options: [{ functions: "never" }],
             parserOptions: { ecmaVersion: 8 },
-            errors: [{ message: "Unexpected trailing comma.", type: "Identifier" }]
+            errors: [{ messageId: "unexpected", type: "Identifier" }]
         },
         {
             code: "(function foo(a,) {})",
             output: "(function foo(a) {})",
             options: [{ functions: "never" }],
             parserOptions: { ecmaVersion: 8 },
-            errors: [{ message: "Unexpected trailing comma.", type: "Identifier" }]
+            errors: [{ messageId: "unexpected", type: "Identifier" }]
         },
         {
             code: "(a,) => a",
             output: "(a) => a",
             options: [{ functions: "never" }],
             parserOptions: { ecmaVersion: 8 },
-            errors: [{ message: "Unexpected trailing comma.", type: "Identifier" }]
+            errors: [{ messageId: "unexpected", type: "Identifier" }]
         },
         {
             code: "(a,) => (a)",
             output: "(a) => (a)",
             options: [{ functions: "never" }],
             parserOptions: { ecmaVersion: 8 },
-            errors: [{ message: "Unexpected trailing comma.", type: "Identifier" }]
+            errors: [{ messageId: "unexpected", type: "Identifier" }]
         },
         {
             code: "({foo(a,) {}})",
             output: "({foo(a) {}})",
             options: [{ functions: "never" }],
             parserOptions: { ecmaVersion: 8 },
-            errors: [{ message: "Unexpected trailing comma.", type: "Identifier" }]
+            errors: [{ messageId: "unexpected", type: "Identifier" }]
         },
         {
             code: "class A {foo(a,) {}}",
             output: "class A {foo(a) {}}",
             options: [{ functions: "never" }],
             parserOptions: { ecmaVersion: 8 },
-            errors: [{ message: "Unexpected trailing comma.", type: "Identifier" }]
+            errors: [{ messageId: "unexpected", type: "Identifier" }]
         },
         {
             code: "foo(a,)",
             output: "foo(a)",
             options: [{ functions: "never" }],
             parserOptions: { ecmaVersion: 8 },
-            errors: [{ message: "Unexpected trailing comma.", type: "Identifier" }]
+            errors: [{ messageId: "unexpected", type: "Identifier" }]
         },
         {
             code: "foo(...a,)",
             output: "foo(...a)",
             options: [{ functions: "never" }],
             parserOptions: { ecmaVersion: 8 },
-            errors: [{ message: "Unexpected trailing comma.", type: "SpreadElement" }]
+            errors: [{ messageId: "unexpected", type: "SpreadElement" }]
         },
 
         {
@@ -1154,56 +1154,56 @@ ruleTester.run("comma-dangle", rule, {
             output: "function foo(a,) {}",
             options: [{ functions: "always" }],
             parserOptions: { ecmaVersion: 8 },
-            errors: [{ message: "Missing trailing comma.", type: "Identifier" }]
+            errors: [{ messageId: "missing", type: "Identifier" }]
         },
         {
             code: "(function foo(a) {})",
             output: "(function foo(a,) {})",
             options: [{ functions: "always" }],
             parserOptions: { ecmaVersion: 8 },
-            errors: [{ message: "Missing trailing comma.", type: "Identifier" }]
+            errors: [{ messageId: "missing", type: "Identifier" }]
         },
         {
             code: "(a) => a",
             output: "(a,) => a",
             options: [{ functions: "always" }],
             parserOptions: { ecmaVersion: 8 },
-            errors: [{ message: "Missing trailing comma.", type: "Identifier" }]
+            errors: [{ messageId: "missing", type: "Identifier" }]
         },
         {
             code: "(a) => (a)",
             output: "(a,) => (a)",
             options: [{ functions: "always" }],
             parserOptions: { ecmaVersion: 8 },
-            errors: [{ message: "Missing trailing comma.", type: "Identifier" }]
+            errors: [{ messageId: "missing", type: "Identifier" }]
         },
         {
             code: "({foo(a) {}})",
             output: "({foo(a,) {}})",
             options: [{ functions: "always" }],
             parserOptions: { ecmaVersion: 8 },
-            errors: [{ message: "Missing trailing comma.", type: "Identifier" }]
+            errors: [{ messageId: "missing", type: "Identifier" }]
         },
         {
             code: "class A {foo(a) {}}",
             output: "class A {foo(a,) {}}",
             options: [{ functions: "always" }],
             parserOptions: { ecmaVersion: 8 },
-            errors: [{ message: "Missing trailing comma.", type: "Identifier" }]
+            errors: [{ messageId: "missing", type: "Identifier" }]
         },
         {
             code: "foo(a)",
             output: "foo(a,)",
             options: [{ functions: "always" }],
             parserOptions: { ecmaVersion: 8 },
-            errors: [{ message: "Missing trailing comma.", type: "Identifier" }]
+            errors: [{ messageId: "missing", type: "Identifier" }]
         },
         {
             code: "foo(...a)",
             output: "foo(...a,)",
             options: [{ functions: "always" }],
             parserOptions: { ecmaVersion: 8 },
-            errors: [{ message: "Missing trailing comma.", type: "SpreadElement" }]
+            errors: [{ messageId: "missing", type: "SpreadElement" }]
         },
 
         {
@@ -1211,49 +1211,49 @@ ruleTester.run("comma-dangle", rule, {
             output: "function foo(a) {}",
             options: [{ functions: "always-multiline" }],
             parserOptions: { ecmaVersion: 8 },
-            errors: [{ message: "Unexpected trailing comma.", type: "Identifier" }]
+            errors: [{ messageId: "unexpected", type: "Identifier" }]
         },
         {
             code: "(function foo(a,) {})",
             output: "(function foo(a) {})",
             options: [{ functions: "always-multiline" }],
             parserOptions: { ecmaVersion: 8 },
-            errors: [{ message: "Unexpected trailing comma.", type: "Identifier" }]
+            errors: [{ messageId: "unexpected", type: "Identifier" }]
         },
         {
             code: "foo(a,)",
             output: "foo(a)",
             options: [{ functions: "always-multiline" }],
             parserOptions: { ecmaVersion: 8 },
-            errors: [{ message: "Unexpected trailing comma.", type: "Identifier" }]
+            errors: [{ messageId: "unexpected", type: "Identifier" }]
         },
         {
             code: "foo(...a,)",
             output: "foo(...a)",
             options: [{ functions: "always-multiline" }],
             parserOptions: { ecmaVersion: 8 },
-            errors: [{ message: "Unexpected trailing comma.", type: "SpreadElement" }]
+            errors: [{ messageId: "unexpected", type: "SpreadElement" }]
         },
         {
             code: "function foo(\na,\nb\n) {}",
             output: "function foo(\na,\nb,\n) {}",
             options: [{ functions: "always-multiline" }],
             parserOptions: { ecmaVersion: 8 },
-            errors: [{ message: "Missing trailing comma.", type: "Identifier" }]
+            errors: [{ messageId: "missing", type: "Identifier" }]
         },
         {
             code: "foo(\na,\nb\n)",
             output: "foo(\na,\nb,\n)",
             options: [{ functions: "always-multiline" }],
             parserOptions: { ecmaVersion: 8 },
-            errors: [{ message: "Missing trailing comma.", type: "Identifier" }]
+            errors: [{ messageId: "missing", type: "Identifier" }]
         },
         {
             code: "foo(\n...a,\n...b\n)",
             output: "foo(\n...a,\n...b,\n)",
             options: [{ functions: "always-multiline" }],
             parserOptions: { ecmaVersion: 8 },
-            errors: [{ message: "Missing trailing comma.", type: "SpreadElement" }]
+            errors: [{ messageId: "missing", type: "SpreadElement" }]
         },
 
         {
@@ -1261,28 +1261,28 @@ ruleTester.run("comma-dangle", rule, {
             output: "function foo(a) {}",
             options: [{ functions: "only-multiline" }],
             parserOptions: { ecmaVersion: 8 },
-            errors: [{ message: "Unexpected trailing comma.", type: "Identifier" }]
+            errors: [{ messageId: "unexpected", type: "Identifier" }]
         },
         {
             code: "(function foo(a,) {})",
             output: "(function foo(a) {})",
             options: [{ functions: "only-multiline" }],
             parserOptions: { ecmaVersion: 8 },
-            errors: [{ message: "Unexpected trailing comma.", type: "Identifier" }]
+            errors: [{ messageId: "unexpected", type: "Identifier" }]
         },
         {
             code: "foo(a,)",
             output: "foo(a)",
             options: [{ functions: "only-multiline" }],
             parserOptions: { ecmaVersion: 8 },
-            errors: [{ message: "Unexpected trailing comma.", type: "Identifier" }]
+            errors: [{ messageId: "unexpected", type: "Identifier" }]
         },
         {
             code: "foo(...a,)",
             output: "foo(...a)",
             options: [{ functions: "only-multiline" }],
             parserOptions: { ecmaVersion: 8 },
-            errors: [{ message: "Unexpected trailing comma.", type: "SpreadElement" }]
+            errors: [{ messageId: "unexpected", type: "SpreadElement" }]
         },
 
         // separated options
@@ -1306,8 +1306,8 @@ export {d,};
             }],
             parserOptions: { ecmaVersion: 8, sourceType: "module" },
             errors: [
-                { message: "Unexpected trailing comma.", line: 1 },
-                { message: "Unexpected trailing comma.", line: 1 }
+                { messageId: "unexpected", line: 1 },
+                { messageId: "unexpected", line: 1 }
             ]
         },
         {
@@ -1330,8 +1330,8 @@ export {d,};
             }],
             parserOptions: { ecmaVersion: 8, sourceType: "module" },
             errors: [
-                { message: "Unexpected trailing comma.", line: 2 },
-                { message: "Unexpected trailing comma.", line: 2 }
+                { messageId: "unexpected", line: 2 },
+                { messageId: "unexpected", line: 2 }
             ]
         },
         {
@@ -1354,7 +1354,7 @@ export {d,};
             }],
             parserOptions: { ecmaVersion: 8, sourceType: "module" },
             errors: [
-                { message: "Unexpected trailing comma.", line: 3 }
+                { messageId: "unexpected", line: 3 }
             ]
         },
         {
@@ -1377,7 +1377,7 @@ export {d};
             }],
             parserOptions: { ecmaVersion: 8, sourceType: "module" },
             errors: [
-                { message: "Unexpected trailing comma.", line: 4 }
+                { messageId: "unexpected", line: 4 }
             ]
         },
         {
@@ -1400,8 +1400,8 @@ export {d,};
             }],
             parserOptions: { ecmaVersion: 8, sourceType: "module" },
             errors: [
-                { message: "Unexpected trailing comma.", line: 5 },
-                { message: "Unexpected trailing comma.", line: 5 }
+                { messageId: "unexpected", line: 5 },
+                { messageId: "unexpected", line: 5 }
             ]
         },
 
@@ -1410,28 +1410,28 @@ export {d,};
             code: "function foo({a}: {a: string,}) {}",
             output: "function foo({a,}: {a: string,}) {}",
             options: ["always"],
-            errors: [{ message: "Missing trailing comma." }],
+            errors: [{ messageId: "missing" }],
             parser: parser("object-pattern-1")
         },
         {
             code: "function foo({a,}: {a: string}) {}",
             output: "function foo({a}: {a: string}) {}",
             options: ["never"],
-            errors: [{ message: "Unexpected trailing comma." }],
+            errors: [{ messageId: "unexpected" }],
             parser: parser("object-pattern-2")
         },
         {
             code: "function foo(a): {b: boolean,} {}",
             output: "function foo(a,): {b: boolean,} {}",
             options: [{ functions: "always" }],
-            errors: [{ message: "Missing trailing comma." }],
+            errors: [{ messageId: "missing" }],
             parser: parser("return-type-1")
         },
         {
             code: "function foo(a,): {b: boolean} {}",
             output: "function foo(a): {b: boolean} {}",
             options: [{ functions: "never" }],
-            errors: [{ message: "Unexpected trailing comma." }],
+            errors: [{ messageId: "unexpected" }],
             parser: parser("return-type-2")
         }
     ]
diff --git a/tests/lib/rules/comma-spacing.js b/tests/lib/rules/comma-spacing.js
index f166360d636..d5c8ff0ec84 100644
--- a/tests/lib/rules/comma-spacing.js
+++ b/tests/lib/rules/comma-spacing.js
@@ -131,11 +131,13 @@ ruleTester.run("comma-spacing", rule, {
             options: [{ before: true, after: true }],
             errors: [
                 {
-                    message: "A space is required before ','.",
+                    messageId: "missing",
+                    data: { loc: "before" },
                     type: "Punctuator"
                 },
                 {
-                    message: "A space is required after ','.",
+                    messageId: "missing",
+                    data: { loc: "after" },
                     type: "Punctuator"
                 }
             ]
@@ -146,11 +148,13 @@ ruleTester.run("comma-spacing", rule, {
             options: [{ before: true, after: true }],
             errors: [
                 {
-                    message: "A space is required before ','.",
+                    messageId: "missing",
+                    data: { loc: "before" },
                     type: "Punctuator"
                 },
                 {
-                    message: "A space is required after ','.",
+                    messageId: "missing",
+                    data: { loc: "after" },
                     type: "Punctuator"
                 }
             ]
@@ -164,7 +168,8 @@ ruleTester.run("comma-spacing", rule, {
                     type: "Punctuator"
                 },
                 {
-                    message: "A space is required after ','.",
+                    messageId: "missing",
+                    data: { loc: "after" },
                     type: "Punctuator"
                 }
             ]
@@ -209,7 +214,8 @@ ruleTester.run("comma-spacing", rule, {
                     type: "Punctuator"
                 },
                 {
-                    message: "A space is required after ','.",
+                    messageId: "missing",
+                    data: { loc: "after" },
                     type: "Punctuator"
                 }
             ]
@@ -230,7 +236,8 @@ ruleTester.run("comma-spacing", rule, {
             options: [{ before: true, after: false }],
             errors: [
                 {
-                    message: "A space is required before ','.",
+                    messageId: "missing",
+                    data: { loc: "before" },
                     type: "Punctuator"
                 },
                 {
@@ -256,7 +263,8 @@ ruleTester.run("comma-spacing", rule, {
             options: [{ before: true, after: false }],
             errors: [
                 {
-                    message: "A space is required before ','.",
+                    messageId: "missing",
+                    data: { loc: "before" },
                     type: "Punctuator"
                 }
             ]
@@ -267,7 +275,8 @@ ruleTester.run("comma-spacing", rule, {
             options: [{ before: true, after: false }],
             errors: [
                 {
-                    message: "A space is required before ','.",
+                    messageId: "missing",
+                    data: { loc: "before" },
                     type: "Punctuator"
                 },
                 {
@@ -282,7 +291,8 @@ ruleTester.run("comma-spacing", rule, {
             options: [{ before: false, after: true }],
             errors: [
                 {
-                    message: "A space is required after ','.",
+                    messageId: "missing",
+                    data: { loc: "after" },
                     type: "Punctuator"
                 }
             ]
@@ -304,7 +314,8 @@ ruleTester.run("comma-spacing", rule, {
             options: [{ before: true, after: true }],
             errors: [
                 {
-                    message: "A space is required after ','.",
+                    messageId: "missing",
+                    data: { loc: "after" },
                     type: "Punctuator"
                 }
             ]
@@ -315,11 +326,13 @@ ruleTester.run("comma-spacing", rule, {
             options: [{ before: true, after: true }],
             errors: [
                 {
-                    message: "A space is required before ','.",
+                    messageId: "missing",
+                    data: { loc: "before" },
                     type: "Punctuator"
                 },
                 {
-                    message: "A space is required after ','.",
+                    messageId: "missing",
+                    data: { loc: "after" },
                     type: "Punctuator"
                 }
             ]
@@ -330,11 +343,13 @@ ruleTester.run("comma-spacing", rule, {
             options: [{ before: true, after: true }],
             errors: [
                 {
-                    message: "A space is required before ','.",
+                    messageId: "missing",
+                    data: { loc: "before" },
                     type: "Punctuator"
                 },
                 {
-                    message: "A space is required after ','.",
+                    messageId: "missing",
+                    data: { loc: "after" },
                     type: "Punctuator"
                 }
             ]
@@ -364,7 +379,8 @@ ruleTester.run("comma-spacing", rule, {
                     type: "Punctuator"
                 },
                 {
-                    message: "A space is required after ','.",
+                    messageId: "missing",
+                    data: { loc: "after" },
                     type: "Punctuator"
                 }
             ]
@@ -375,11 +391,13 @@ ruleTester.run("comma-spacing", rule, {
             options: [{ before: true, after: true }],
             errors: [
                 {
-                    message: "A space is required before ','.",
+                    messageId: "missing",
+                    data: { loc: "before" },
                     type: "Punctuator"
                 },
                 {
-                    message: "A space is required after ','.",
+                    messageId: "missing",
+                    data: { loc: "after" },
                     type: "Punctuator"
                 }
             ]
@@ -391,11 +409,13 @@ ruleTester.run("comma-spacing", rule, {
             parserOptions: { ecmaVersion: 6 },
             errors: [
                 {
-                    message: "A space is required before ','.",
+                    messageId: "missing",
+                    data: { loc: "before" },
                     type: "Punctuator"
                 },
                 {
-                    message: "A space is required after ','.",
+                    messageId: "missing",
+                    data: { loc: "after" },
                     type: "Punctuator"
                 }
             ]
@@ -407,11 +427,13 @@ ruleTester.run("comma-spacing", rule, {
             parserOptions: { ecmaVersion: 6 },
             errors: [
                 {
-                    message: "A space is required before ','.",
+                    messageId: "missing",
+                    data: { loc: "before" },
                     type: "Punctuator"
                 },
                 {
-                    message: "A space is required after ','.",
+                    messageId: "missing",
+                    data: { loc: "after" },
                     type: "Punctuator"
                 }
             ]
@@ -427,7 +449,8 @@ ruleTester.run("comma-spacing", rule, {
                     type: "Punctuator"
                 },
                 {
-                    message: "A space is required after ','.",
+                    messageId: "missing",
+                    data: { loc: "after" },
                     type: "Punctuator"
                 }
             ]
@@ -442,7 +465,8 @@ ruleTester.run("comma-spacing", rule, {
                     type: "Punctuator"
                 },
                 {
-                    message: "A space is required after ','.",
+                    messageId: "missing",
+                    data: { loc: "after" },
                     type: "Punctuator"
                 }
             ]
@@ -462,7 +486,8 @@ ruleTester.run("comma-spacing", rule, {
             output: "myfunc(404, true, /* bla bla bla */ 'hello');",
             errors: [
                 {
-                    message: "A space is required after ','.",
+                    messageId: "missing",
+                    data: { loc: "after" },
                     type: "Punctuator"
                 }
             ]
@@ -472,7 +497,8 @@ ruleTester.run("comma-spacing", rule, {
             output: "myfunc(404, // comment\n true, 'hello');",
             errors: [
                 {
-                    message: "A space is required after ','.",
+                    messageId: "missing",
+                    data: { loc: "after" },
                     type: "Punctuator"
                 }
             ]
diff --git a/tests/lib/rules/comma-style.js b/tests/lib/rules/comma-style.js
index d8bf438c7a4..2bed575bf86 100644
--- a/tests/lib/rules/comma-style.js
+++ b/tests/lib/rules/comma-style.js
@@ -11,10 +11,6 @@
 const rule = require("../../../lib/rules/comma-style"),
     RuleTester = require("../../../lib/testers/rule-tester");
 
-const BAD_LN_BRK_MSG = "Bad line breaking before and after ','.",
-    FIRST_MSG = "',' should be placed first.",
-    LAST_MSG = "',' should be placed last.";
-
 //------------------------------------------------------------------------------
 // Tests
 //------------------------------------------------------------------------------
@@ -245,7 +241,7 @@ ruleTester.run("comma-style", rule, {
             code: "var foo = { a: 1. //comment \n, b: 2\n}",
             output: "var foo = { a: 1., //comment \n b: 2\n}",
             errors: [{
-                message: LAST_MSG,
+                messageId: "expectedCommaLast",
                 type: "Property"
             }]
         },
@@ -253,7 +249,7 @@ ruleTester.run("comma-style", rule, {
             code: "var foo = { a: 1. //comment \n //comment1 \n //comment2 \n, b: 2\n}",
             output: "var foo = { a: 1., //comment \n //comment1 \n //comment2 \n b: 2\n}",
             errors: [{
-                message: LAST_MSG,
+                messageId: "expectedCommaLast",
                 type: "Property"
             }]
         },
@@ -261,7 +257,7 @@ ruleTester.run("comma-style", rule, {
             code: "var foo = 1\n,\nbar = 2;",
             output: "var foo = 1,\nbar = 2;",
             errors: [{
-                message: BAD_LN_BRK_MSG,
+                messageId: "unexpectedLineBeforeAndAfterComma",
                 type: "VariableDeclarator"
             }]
         },
@@ -269,7 +265,7 @@ ruleTester.run("comma-style", rule, {
             code: "var foo = 1 //comment\n,\nbar = 2;",
             output: "var foo = 1, //comment\nbar = 2;",
             errors: [{
-                message: BAD_LN_BRK_MSG,
+                messageId: "unexpectedLineBeforeAndAfterComma",
                 type: "VariableDeclarator"
             }]
         },
@@ -277,7 +273,7 @@ ruleTester.run("comma-style", rule, {
             code: "var foo = 1 //comment\n, // comment 2\nbar = 2;",
             output: "var foo = 1, //comment // comment 2\nbar = 2;",
             errors: [{
-                message: BAD_LN_BRK_MSG,
+                messageId: "unexpectedLineBeforeAndAfterComma",
                 type: "VariableDeclarator"
             }]
         },
@@ -289,13 +285,13 @@ ruleTester.run("comma-style", rule, {
                     NewExpression: false
                 }
             }],
-            errors: [{ message: BAD_LN_BRK_MSG }]
+            errors: [{ messageId: "unexpectedLineBeforeAndAfterComma" }]
         },
         {
             code: "var foo = 1\n,bar = 2;",
             output: "var foo = 1,\nbar = 2;",
             errors: [{
-                message: LAST_MSG,
+                messageId: "expectedCommaLast",
                 type: "VariableDeclarator"
             }]
         },
@@ -303,7 +299,7 @@ ruleTester.run("comma-style", rule, {
             code: "f([1,2\n,3]);",
             output: "f([1,2,\n3]);",
             errors: [{
-                message: LAST_MSG,
+                messageId: "expectedCommaLast",
                 type: "Literal"
             }]
         },
@@ -311,7 +307,7 @@ ruleTester.run("comma-style", rule, {
             code: "f([1,2\n,]);",
             output: "f([1,2,\n]);",
             errors: [{
-                message: LAST_MSG,
+                messageId: "expectedCommaLast",
                 type: "Punctuator"
             }]
         },
@@ -319,7 +315,7 @@ ruleTester.run("comma-style", rule, {
             code: "f([,2\n,3]);",
             output: "f([,2,\n3]);",
             errors: [{
-                message: LAST_MSG,
+                messageId: "expectedCommaLast",
                 type: "Literal"
             }]
         },
@@ -327,7 +323,7 @@ ruleTester.run("comma-style", rule, {
             code: "var foo = ['apples'\n, 'oranges'];",
             output: "var foo = ['apples',\n 'oranges'];",
             errors: [{
-                message: LAST_MSG,
+                messageId: "expectedCommaLast",
                 type: "Literal"
             }]
         },
@@ -343,7 +339,7 @@ ruleTester.run("comma-style", rule, {
                 ecmaVersion: 6
             },
             errors: [{
-                message: LAST_MSG,
+                messageId: "expectedCommaLast",
                 type: "Identifier"
             }]
         },
@@ -356,7 +352,7 @@ ruleTester.run("comma-style", rule, {
                 }
             }],
             errors: [{
-                message: LAST_MSG,
+                messageId: "expectedCommaLast",
                 type: "Literal"
             }]
         },
@@ -369,7 +365,7 @@ ruleTester.run("comma-style", rule, {
                 }
             }],
             errors: [{
-                message: LAST_MSG,
+                messageId: "expectedCommaLast",
                 type: "Identifier"
             }]
         },
@@ -386,7 +382,7 @@ ruleTester.run("comma-style", rule, {
                 sourceType: "module"
             },
             errors: [{
-                message: LAST_MSG,
+                messageId: "expectedCommaLast",
                 type: "Identifier"
             }]
         },
@@ -402,7 +398,7 @@ ruleTester.run("comma-style", rule, {
                 ecmaVersion: 6
             },
             errors: [{
-                message: LAST_MSG,
+                messageId: "expectedCommaLast",
                 type: "Identifier"
             }]
         },
@@ -418,7 +414,7 @@ ruleTester.run("comma-style", rule, {
                 ecmaVersion: 6
             },
             errors: [{
-                message: LAST_MSG,
+                messageId: "expectedCommaLast",
                 type: "Identifier"
             }]
         },
@@ -434,7 +430,7 @@ ruleTester.run("comma-style", rule, {
                 ecmaVersion: 6
             },
             errors: [{
-                message: LAST_MSG,
+                messageId: "expectedCommaLast",
                 type: "Identifier"
             }]
         },
@@ -451,7 +447,7 @@ ruleTester.run("comma-style", rule, {
                 sourceType: "module"
             },
             errors: [{
-                message: LAST_MSG,
+                messageId: "expectedCommaLast",
                 type: "ImportSpecifier"
             }]
         },
@@ -467,7 +463,7 @@ ruleTester.run("comma-style", rule, {
                 ecmaVersion: 6
             },
             errors: [{
-                message: LAST_MSG,
+                messageId: "expectedCommaLast",
                 type: "Property"
             }]
         },
@@ -476,7 +472,7 @@ ruleTester.run("comma-style", rule, {
             output: "var foo = 1\n,bar = 2;",
             options: ["first"],
             errors: [{
-                message: FIRST_MSG,
+                messageId: "expectedCommaFirst",
                 type: "VariableDeclarator"
             }]
         },
@@ -485,7 +481,7 @@ ruleTester.run("comma-style", rule, {
             output: "f([1\n,2,3]);",
             options: ["first"],
             errors: [{
-                message: FIRST_MSG,
+                messageId: "expectedCommaFirst",
                 type: "Literal"
             }]
         },
@@ -494,7 +490,7 @@ ruleTester.run("comma-style", rule, {
             output: "var foo = ['apples' \n ,'oranges'];",
             options: ["first"],
             errors: [{
-                message: FIRST_MSG,
+                messageId: "expectedCommaFirst",
                 type: "Literal"
             }]
         },
@@ -503,7 +499,7 @@ ruleTester.run("comma-style", rule, {
             output: "var foo = {'a': 1 \n ,'b': 2\n ,'c': 3};",
             options: ["first"],
             errors: [{
-                message: FIRST_MSG,
+                messageId: "expectedCommaFirst",
                 type: "Property"
             }]
         },
@@ -512,7 +508,7 @@ ruleTester.run("comma-style", rule, {
             output: "var a = 'a',\no = 'o',\narr = [1\n,2];",
             options: ["first", { exceptions: { VariableDeclaration: true } }],
             errors: [{
-                message: FIRST_MSG,
+                messageId: "expectedCommaFirst",
                 type: "Literal"
             }]
         },
@@ -521,7 +517,7 @@ ruleTester.run("comma-style", rule, {
             output: "var a = 'a',\nobj = {a: 'a'\n,b: 'b'};",
             options: ["first", { exceptions: { VariableDeclaration: true } }],
             errors: [{
-                message: FIRST_MSG,
+                messageId: "expectedCommaFirst",
                 type: "Property"
             }]
         },
@@ -530,7 +526,7 @@ ruleTester.run("comma-style", rule, {
             output: "var a = 'a'\n,obj = {a: 'a',\nb: 'b'};",
             options: ["first", { exceptions: { ObjectExpression: true } }],
             errors: [{
-                message: FIRST_MSG,
+                messageId: "expectedCommaFirst",
                 type: "VariableDeclarator"
             }]
         },
@@ -539,7 +535,7 @@ ruleTester.run("comma-style", rule, {
             output: "var a = 'a'\n,arr = [1,\n2];",
             options: ["first", { exceptions: { ArrayExpression: true } }],
             errors: [{
-                message: FIRST_MSG,
+                messageId: "expectedCommaFirst",
                 type: "VariableDeclarator"
             }]
         },
@@ -548,7 +544,7 @@ ruleTester.run("comma-style", rule, {
             output: "var ar =[1,\n{a: 'a'\n,b: 'b'}];",
             options: ["first", { exceptions: { ArrayExpression: true } }],
             errors: [{
-                message: FIRST_MSG,
+                messageId: "expectedCommaFirst",
                 type: "Property"
             }]
         },
@@ -557,7 +553,7 @@ ruleTester.run("comma-style", rule, {
             output: "var ar =[1\n,{a: 'a',\nb: 'b'}];",
             options: ["first", { exceptions: { ObjectExpression: true } }],
             errors: [{
-                message: FIRST_MSG,
+                messageId: "expectedCommaFirst",
                 type: "ObjectExpression"
             }]
         },
@@ -566,7 +562,7 @@ ruleTester.run("comma-style", rule, {
             output: "var ar ={fst:1,\nsnd: [1\n,2]};",
             options: ["first", { exceptions: { ObjectExpression: true } }],
             errors: [{
-                message: FIRST_MSG,
+                messageId: "expectedCommaFirst",
                 type: "Literal"
             }]
         },
@@ -575,7 +571,7 @@ ruleTester.run("comma-style", rule, {
             output: "var ar ={fst:1\n,snd: [1,\n2]};",
             options: ["first", { exceptions: { ArrayExpression: true } }],
             errors: [{
-                message: FIRST_MSG,
+                messageId: "expectedCommaFirst",
                 type: "Property"
             }]
         },
@@ -587,20 +583,20 @@ ruleTester.run("comma-style", rule, {
                     NewExpression: false
                 }
             }],
-            errors: [{ message: FIRST_MSG }]
+            errors: [{ messageId: "expectedCommaFirst" }]
         },
         {
             code: "var foo = [\n(bar\n)\n,\nbaz\n];",
             output: "var foo = [\n(bar\n),\nbaz\n];",
             errors: [{
-                message: BAD_LN_BRK_MSG,
+                messageId: "unexpectedLineBeforeAndAfterComma",
                 type: "Identifier"
             }]
         },
         {
             code: "[(foo),\n,\nbar]",
             output: "[(foo),,\nbar]",
-            errors: [{ message: BAD_LN_BRK_MSG }]
+            errors: [{ messageId: "unexpectedLineBeforeAndAfterComma" }]
         },
         {
             code: "new Foo(a\n,b);",
@@ -610,7 +606,7 @@ ruleTester.run("comma-style", rule, {
                     NewExpression: false
                 }
             }],
-            errors: [{ message: LAST_MSG }]
+            errors: [{ messageId: "expectedCommaLast" }]
         }
     ]
 });
diff --git a/tests/lib/rules/complexity.js b/tests/lib/rules/complexity.js
index 9e2b5d92b5d..159d27c8c26 100644
--- a/tests/lib/rules/complexity.js
+++ b/tests/lib/rules/complexity.js
@@ -34,6 +34,19 @@ function createComplexity(complexity) {
     return funcString;
 }
 
+/**
+ * Create an expected error object
+ * @param   {string} name       The name of the symbol being tested
+ * @param   {number} complexity The cyclomatic complexity value of the symbol
+ * @returns {Object}            The error object
+ */
+function makeError(name, complexity) {
+    return {
+        messageId: "complex",
+        data: { name, complexity }
+    };
+}
+
 const ruleTester = new RuleTester();
 
 ruleTester.run("complexity", rule, {
@@ -63,10 +76,10 @@ ruleTester.run("complexity", rule, {
         { code: "function b(x) {}", options: [{ max: 1 }] }
     ],
     invalid: [
-        { code: "function a(x) {}", options: [0], errors: [{ message: "Function 'a' has a complexity of 1." }] },
-        { code: "var func = function () {}", options: [0], errors: [{ message: "Function has a complexity of 1." }] },
-        { code: "var obj = { a(x) {} }", options: [0], parserOptions: { ecmaVersion: 6 }, errors: [{ message: "Method 'a' has a complexity of 1." }] },
-        { code: "class Test { a(x) {} }", options: [0], parserOptions: { ecmaVersion: 6 }, errors: [{ message: "Method 'a' has a complexity of 1." }] },
+        { code: "function a(x) {}", options: [0], errors: [makeError("Function 'a'", 1)] },
+        { code: "var func = function () {}", options: [0], errors: [makeError("Function", 1)] },
+        { code: "var obj = { a(x) {} }", options: [0], parserOptions: { ecmaVersion: 6 }, errors: [makeError("Method 'a'", 1)] },
+        { code: "class Test { a(x) {} }", options: [0], parserOptions: { ecmaVersion: 6 }, errors: [makeError("Method 'a'", 1)] },
         { code: "var a = (x) => {if (true) {return x;}}", options: [1], errors: 1, settings: { ecmascript: 6 } },
         { code: "function a(x) {if (true) {return x;}}", options: [1], errors: 1 },
         { code: "function a(x) {if (true) {return x;} else {return x+1;}}", options: [1], errors: 1 },
@@ -87,14 +100,14 @@ ruleTester.run("complexity", rule, {
         { code: "function a(x) {do {'foo';} while (true)}", options: [1], errors: 1 },
         { code: "function a(x) {(function() {while(true){'foo';}})(); (function() {while(true){'bar';}})();}", options: [1], errors: 2 },
         { code: "function a(x) {(function() {while(true){'foo';}})(); (function() {'bar';})();}", options: [1], errors: 1 },
-        { code: "var obj = { a(x) { return x ? 0 : 1; } };", options: [1], parserOptions: { ecmaVersion: 6 }, errors: [{ message: "Method 'a' has a complexity of 2." }] },
-        { code: "var obj = { a: function b(x) { return x ? 0 : 1; } };", options: [1], errors: [{ message: "Method 'b' has a complexity of 2." }] },
+        { code: "var obj = { a(x) { return x ? 0 : 1; } };", options: [1], parserOptions: { ecmaVersion: 6 }, errors: [makeError("Method 'a'", 2)] },
+        { code: "var obj = { a: function b(x) { return x ? 0 : 1; } };", options: [1], errors: [makeError("Method 'b'", 2)] },
         {
             code: createComplexity(21),
-            errors: [{ message: "Function 'test' has a complexity of 21." }]
+            errors: [makeError("Function 'test'", 21)]
         },
 
         // object property options
-        { code: "function a(x) {}", options: [{ max: 0 }], errors: [{ message: "Function 'a' has a complexity of 1." }] }
+        { code: "function a(x) {}", options: [{ max: 0 }], errors: [makeError("Function 'a'", 1)] }
     ]
 });
diff --git a/tests/lib/rules/computed-property-spacing.js b/tests/lib/rules/computed-property-spacing.js
index eadc7eabed4..b5a4825286e 100644
--- a/tests/lib/rules/computed-property-spacing.js
+++ b/tests/lib/rules/computed-property-spacing.js
@@ -82,7 +82,8 @@ ruleTester.run("computed-property-spacing", rule, {
             options: ["always"],
             errors: [
                 {
-                    message: "A space is required before ']'.",
+                    messageId: "missingSpaceBefore",
+                    data: { tokenValue: "]" },
                     type: "MemberExpression",
                     column: 17,
                     line: 1
@@ -95,7 +96,8 @@ ruleTester.run("computed-property-spacing", rule, {
             options: ["always"],
             errors: [
                 {
-                    message: "A space is required after '['.",
+                    messageId: "missingSpaceAfter",
+                    data: { tokenValue: "[" },
                     type: "MemberExpression",
                     column: 14,
                     line: 1
@@ -108,7 +110,8 @@ ruleTester.run("computed-property-spacing", rule, {
             options: ["never"],
             errors: [
                 {
-                    message: "There should be no space after '['.",
+                    messageId: "unexpectedSpaceAfter",
+                    data: { tokenValue: "[" },
                     type: "MemberExpression",
                     column: 14,
                     line: 1
@@ -121,7 +124,8 @@ ruleTester.run("computed-property-spacing", rule, {
             options: ["never"],
             errors: [
                 {
-                    message: "There should be no space before ']'.",
+                    messageId: "unexpectedSpaceBefore",
+                    data: { tokenValue: "]" },
                     type: "MemberExpression"
                 }
             ]
@@ -132,13 +136,15 @@ ruleTester.run("computed-property-spacing", rule, {
             options: ["never"],
             errors: [
                 {
-                    message: "There should be no space after '['.",
+                    messageId: "unexpectedSpaceAfter",
+                    data: { tokenValue: "[" },
                     type: "MemberExpression",
                     column: 4,
                     line: 1
                 },
                 {
-                    message: "There should be no space before ']'.",
+                    messageId: "unexpectedSpaceBefore",
+                    data: { tokenValue: "]" },
                     type: "MemberExpression",
                     column: 10,
                     line: 1
@@ -151,7 +157,8 @@ ruleTester.run("computed-property-spacing", rule, {
             options: ["never"],
             errors: [
                 {
-                    message: "There should be no space before ']'.",
+                    messageId: "unexpectedSpaceBefore",
+                    data: { tokenValue: "]" },
                     type: "MemberExpression",
                     column: 9,
                     line: 1
@@ -164,7 +171,8 @@ ruleTester.run("computed-property-spacing", rule, {
             options: ["never"],
             errors: [
                 {
-                    message: "There should be no space after '['.",
+                    messageId: "unexpectedSpaceAfter",
+                    data: { tokenValue: "[" },
                     type: "MemberExpression",
                     column: 4,
                     line: 1
@@ -177,13 +185,15 @@ ruleTester.run("computed-property-spacing", rule, {
             options: ["always"],
             errors: [
                 {
-                    message: "A space is required after '['.",
+                    messageId: "missingSpaceAfter",
+                    data: { tokenValue: "[" },
                     type: "MemberExpression",
                     column: 14,
                     line: 1
                 },
                 {
-                    message: "A space is required before ']'.",
+                    messageId: "missingSpaceBefore",
+                    data: { tokenValue: "]" },
                     type: "MemberExpression",
                     column: 16,
                     line: 1
@@ -199,13 +209,15 @@ ruleTester.run("computed-property-spacing", rule, {
             parserOptions: { ecmaVersion: 6 },
             errors: [
                 {
-                    message: "A space is required after '['.",
+                    messageId: "missingSpaceAfter",
+                    data: { tokenValue: "[" },
                     type: "Property",
                     column: 10,
                     line: 1
                 },
                 {
-                    message: "A space is required before ']'.",
+                    messageId: "missingSpaceBefore",
+                    data: { tokenValue: "]" },
                     type: "Property",
                     column: 12,
                     line: 1
@@ -219,7 +231,8 @@ ruleTester.run("computed-property-spacing", rule, {
             parserOptions: { ecmaVersion: 6 },
             errors: [
                 {
-                    message: "A space is required after '['.",
+                    messageId: "missingSpaceAfter",
+                    data: { tokenValue: "[" },
                     type: "Property",
                     column: 10,
                     line: 1
@@ -233,7 +246,8 @@ ruleTester.run("computed-property-spacing", rule, {
             parserOptions: { ecmaVersion: 6 },
             errors: [
                 {
-                    message: "A space is required before ']'.",
+                    messageId: "missingSpaceBefore",
+                    data: { tokenValue: "]" },
                     type: "Property",
                     column: 13,
                     line: 1
@@ -249,13 +263,15 @@ ruleTester.run("computed-property-spacing", rule, {
             parserOptions: { ecmaVersion: 6 },
             errors: [
                 {
-                    message: "There should be no space after '['.",
+                    messageId: "unexpectedSpaceAfter",
+                    data: { tokenValue: "[" },
                     type: "Property",
                     column: 10,
                     line: 1
                 },
                 {
-                    message: "There should be no space before ']'.",
+                    messageId: "unexpectedSpaceBefore",
+                    data: { tokenValue: "]" },
                     type: "Property",
                     column: 14,
                     line: 1
@@ -269,7 +285,8 @@ ruleTester.run("computed-property-spacing", rule, {
             parserOptions: { ecmaVersion: 6 },
             errors: [
                 {
-                    message: "There should be no space before ']'.",
+                    messageId: "unexpectedSpaceBefore",
+                    data: { tokenValue: "]" },
                     type: "Property",
                     column: 13,
                     line: 1
@@ -283,7 +300,8 @@ ruleTester.run("computed-property-spacing", rule, {
             parserOptions: { ecmaVersion: 6 },
             errors: [
                 {
-                    message: "There should be no space after '['.",
+                    messageId: "unexpectedSpaceAfter",
+                    data: { tokenValue: "[" },
                     type: "Property",
                     column: 10,
                     line: 1
@@ -297,7 +315,8 @@ ruleTester.run("computed-property-spacing", rule, {
             parserOptions: { ecmaVersion: 6 },
             errors: [
                 {
-                    message: "There should be no space after '['.",
+                    messageId: "unexpectedSpaceAfter",
+                    data: { tokenValue: "[" },
                     type: "Property",
                     column: 10,
                     line: 1
diff --git a/tests/lib/rules/consistent-return.js b/tests/lib/rules/consistent-return.js
index 2bf4a0d0a1c..15c205500b3 100644
--- a/tests/lib/rules/consistent-return.js
+++ b/tests/lib/rules/consistent-return.js
@@ -50,7 +50,8 @@ ruleTester.run("consistent-return", rule, {
             code: "function foo() { if (true) return true; else return; }",
             errors: [
                 {
-                    message: "Function 'foo' expected a return value.",
+                    messageId: "missingReturnValue",
+                    data: { name: "Function 'foo'" },
                     type: "ReturnStatement"
                 }
             ]
@@ -60,7 +61,8 @@ ruleTester.run("consistent-return", rule, {
             parserOptions: { ecmaVersion: 6 },
             errors: [
                 {
-                    message: "Arrow function expected a return value.",
+                    messageId: "missingReturnValue",
+                    data: { name: "Arrow function" },
                     type: "ReturnStatement"
                 }
             ]
@@ -69,7 +71,8 @@ ruleTester.run("consistent-return", rule, {
             code: "function foo() { if (true) return; else return false; }",
             errors: [
                 {
-                    message: "Function 'foo' expected no return value.",
+                    messageId: "unexpectedReturnValue",
+                    data: { name: "Function 'foo'" },
                     type: "ReturnStatement"
                 }
             ]
@@ -78,7 +81,8 @@ ruleTester.run("consistent-return", rule, {
             code: "f(function() { if (true) return true; else return; })",
             errors: [
                 {
-                    message: "Function expected a return value.",
+                    messageId: "missingReturnValue",
+                    data: { name: "Function" },
                     type: "ReturnStatement"
                 }
             ]
@@ -87,7 +91,8 @@ ruleTester.run("consistent-return", rule, {
             code: "f(function() { if (true) return; else return false; })",
             errors: [
                 {
-                    message: "Function expected no return value.",
+                    messageId: "unexpectedReturnValue",
+                    data: { name: "Function" },
                     type: "ReturnStatement"
                 }
             ]
@@ -97,7 +102,8 @@ ruleTester.run("consistent-return", rule, {
             parserOptions: { ecmaVersion: 6 },
             errors: [
                 {
-                    message: "Arrow function expected no return value.",
+                    messageId: "unexpectedReturnValue",
+                    data: { name: "Arrow function" },
                     type: "ReturnStatement"
                 }
             ]
@@ -107,7 +113,8 @@ ruleTester.run("consistent-return", rule, {
             options: [{ treatUndefinedAsUnspecified: true }],
             errors: [
                 {
-                    message: "Function 'foo' expected a return value.",
+                    messageId: "missingReturnValue",
+                    data: { name: "Function 'foo'" },
                     type: "ReturnStatement",
                     column: 41
                 }
@@ -118,7 +125,8 @@ ruleTester.run("consistent-return", rule, {
             options: [{ treatUndefinedAsUnspecified: true }],
             errors: [
                 {
-                    message: "Function 'foo' expected a return value.",
+                    messageId: "missingReturnValue",
+                    data: { name: "Function 'foo'" },
                     type: "ReturnStatement",
                     column: 41
                 }
@@ -129,7 +137,8 @@ ruleTester.run("consistent-return", rule, {
             options: [{ treatUndefinedAsUnspecified: true }],
             errors: [
                 {
-                    message: "Function 'foo' expected no return value.",
+                    messageId: "unexpectedReturnValue",
+                    data: { name: "Function 'foo'" },
                     type: "ReturnStatement",
                     column: 46
                 }
@@ -140,7 +149,8 @@ ruleTester.run("consistent-return", rule, {
             options: [{ treatUndefinedAsUnspecified: true }],
             errors: [
                 {
-                    message: "Function 'foo' expected no return value.",
+                    messageId: "unexpectedReturnValue",
+                    data: { name: "Function 'foo'" },
                     type: "ReturnStatement",
                     column: 43
                 }
@@ -151,7 +161,8 @@ ruleTester.run("consistent-return", rule, {
             parserOptions: { ecmaFeatures: { globalReturn: true } },
             errors: [
                 {
-                    message: "Program expected a return value.",
+                    messageId: "missingReturnValue",
+                    data: { name: "Program" },
                     type: "ReturnStatement"
                 }
             ]
@@ -160,7 +171,8 @@ ruleTester.run("consistent-return", rule, {
             code: "function foo() { if (a) return true; }",
             errors: [
                 {
-                    message: "Expected to return a value at the end of function 'foo'.",
+                    messageId: "missingReturn",
+                    data: { name: "function 'foo'" },
                     type: "FunctionDeclaration",
                     column: 10
                 }
@@ -170,7 +182,8 @@ ruleTester.run("consistent-return", rule, {
             code: "function _foo() { if (a) return true; }",
             errors: [
                 {
-                    message: "Expected to return a value at the end of function '_foo'.",
+                    messageId: "missingReturn",
+                    data: { name: "function '_foo'" },
                     type: "FunctionDeclaration",
                     column: 10
                 }
@@ -180,7 +193,8 @@ ruleTester.run("consistent-return", rule, {
             code: "f(function foo() { if (a) return true; });",
             errors: [
                 {
-                    message: "Expected to return a value at the end of function 'foo'.",
+                    messageId: "missingReturn",
+                    data: { name: "function 'foo'" },
                     type: "FunctionExpression",
                     column: 12
                 }
@@ -190,7 +204,8 @@ ruleTester.run("consistent-return", rule, {
             code: "f(function() { if (a) return true; });",
             errors: [
                 {
-                    message: "Expected to return a value at the end of function.",
+                    messageId: "missingReturn",
+                    data: { name: "function" },
                     type: "FunctionExpression",
                     column: 3
                 }
@@ -201,7 +216,8 @@ ruleTester.run("consistent-return", rule, {
             parserOptions: { ecmaVersion: 6 },
             errors: [
                 {
-                    message: "Expected to return a value at the end of arrow function.",
+                    messageId: "missingReturn",
+                    data: { name: "arrow function" },
                     type: "ArrowFunctionExpression",
                     column: 6
                 }
@@ -212,7 +228,8 @@ ruleTester.run("consistent-return", rule, {
             parserOptions: { ecmaVersion: 6 },
             errors: [
                 {
-                    message: "Expected to return a value at the end of method 'foo'.",
+                    messageId: "missingReturn",
+                    data: { name: "method 'foo'" },
                     type: "FunctionExpression",
                     column: 12
                 }
@@ -223,7 +240,8 @@ ruleTester.run("consistent-return", rule, {
             parserOptions: { ecmaVersion: 6 },
             errors: [
                 {
-                    message: "Expected to return a value at the end of method 'foo'.",
+                    messageId: "missingReturn",
+                    data: { name: "method 'foo'" },
                     type: "FunctionExpression",
                     column: 10
                 }
@@ -234,7 +252,8 @@ ruleTester.run("consistent-return", rule, {
             parserOptions: { ecmaFeatures: { globalReturn: true } },
             errors: [
                 {
-                    message: "Expected to return a value at the end of program.",
+                    messageId: "missingReturn",
+                    data: { name: "program" },
                     type: "Program",
                     column: 1
                 }
@@ -245,7 +264,8 @@ ruleTester.run("consistent-return", rule, {
             parserOptions: { ecmaVersion: 6 },
             errors: [
                 {
-                    message: "Expected to return a value at the end of method 'CapitalizedFunction'.",
+                    messageId: "missingReturn",
+                    data: { name: "method 'CapitalizedFunction'" },
                     type: "FunctionExpression",
                     column: 11
                 }
@@ -256,7 +276,8 @@ ruleTester.run("consistent-return", rule, {
             parserOptions: { ecmaVersion: 6 },
             errors: [
                 {
-                    message: "Expected to return a value at the end of method 'constructor'.",
+                    messageId: "missingReturn",
+                    data: { name: "method 'constructor'" },
                     type: "FunctionExpression",
                     column: 4
                 }
diff --git a/tests/lib/rules/consistent-this.js b/tests/lib/rules/consistent-this.js
index 782e302d214..7a37dd999e7 100644
--- a/tests/lib/rules/consistent-this.js
+++ b/tests/lib/rules/consistent-this.js
@@ -54,16 +54,16 @@ ruleTester.run("consistent-this", rule, {
         destructuringTest("[foo, bar] = this")
     ],
     invalid: [
-        { code: "var context = this", errors: [{ message: "Unexpected alias 'context' for 'this'.", type: "VariableDeclarator" }] },
-        { code: "var that = this", options: ["self"], errors: [{ message: "Unexpected alias 'that' for 'this'.", type: "VariableDeclarator" }] },
-        { code: "var foo = 42, self = this", options: ["that"], errors: [{ message: "Unexpected alias 'self' for 'this'.", type: "VariableDeclarator" }] },
-        { code: "var self = 42", options: ["self"], errors: [{ message: "Designated alias 'self' is not assigned to 'this'.", type: "VariableDeclarator" }] },
-        { code: "var self", options: ["self"], errors: [{ message: "Designated alias 'self' is not assigned to 'this'.", type: "VariableDeclarator" }] },
-        { code: "var self; self = 42", options: ["self"], errors: [{ message: "Designated alias 'self' is not assigned to 'this'.", type: "VariableDeclarator" }, { message: "Designated alias 'self' is not assigned to 'this'.", type: "AssignmentExpression" }] },
-        { code: "context = this", options: ["that"], errors: [{ message: "Unexpected alias 'context' for 'this'.", type: "AssignmentExpression" }] },
-        { code: "that = this", options: ["self"], errors: [{ message: "Unexpected alias 'that' for 'this'.", type: "AssignmentExpression" }] },
-        { code: "self = this", options: ["that"], errors: [{ message: "Unexpected alias 'self' for 'this'.", type: "AssignmentExpression" }] },
-        { code: "self += this", options: ["self"], errors: [{ message: "Designated alias 'self' is not assigned to 'this'.", type: "AssignmentExpression" }] },
-        { code: "var self; (function() { self = this; }())", options: ["self"], errors: [{ message: "Designated alias 'self' is not assigned to 'this'.", type: "VariableDeclarator" }] }
+        { code: "var context = this", errors: [{ messageId: "unexpectedAlias", data: { name: "context" }, type: "VariableDeclarator" }] },
+        { code: "var that = this", options: ["self"], errors: [{ messageId: "unexpectedAlias", data: { name: "that" }, type: "VariableDeclarator" }] },
+        { code: "var foo = 42, self = this", options: ["that"], errors: [{ messageId: "unexpectedAlias", data: { name: "self" }, type: "VariableDeclarator" }] },
+        { code: "var self = 42", options: ["self"], errors: [{ messageId: "aliasNotAssignedToThis", data: { name: "self" }, type: "VariableDeclarator" }] },
+        { code: "var self", options: ["self"], errors: [{ messageId: "aliasNotAssignedToThis", data: { name: "self" }, type: "VariableDeclarator" }] },
+        { code: "var self; self = 42", options: ["self"], errors: [{ messageId: "aliasNotAssignedToThis", data: { name: "self" }, type: "VariableDeclarator" }, { messageId: "aliasNotAssignedToThis", data: { name: "self" }, type: "AssignmentExpression" }] },
+        { code: "context = this", options: ["that"], errors: [{ messageId: "unexpectedAlias", data: { name: "context" }, type: "AssignmentExpression" }] },
+        { code: "that = this", options: ["self"], errors: [{ messageId: "unexpectedAlias", data: { name: "that" }, type: "AssignmentExpression" }] },
+        { code: "self = this", options: ["that"], errors: [{ messageId: "unexpectedAlias", data: { name: "self" }, type: "AssignmentExpression" }] },
+        { code: "self += this", options: ["self"], errors: [{ messageId: "aliasNotAssignedToThis", data: { name: "self" }, type: "AssignmentExpression" }] },
+        { code: "var self; (function() { self = this; }())", options: ["self"], errors: [{ messageId: "aliasNotAssignedToThis", data: { name: "self" }, type: "VariableDeclarator" }] }
     ]
 });
diff --git a/tests/lib/rules/constructor-super.js b/tests/lib/rules/constructor-super.js
index d4da041f6db..89d5b6193d2 100644
--- a/tests/lib/rules/constructor-super.js
+++ b/tests/lib/rules/constructor-super.js
@@ -102,130 +102,130 @@ ruleTester.run("constructor-super", rule, {
         // non derived classes.
         {
             code: "class A { constructor() { super(); } }",
-            errors: [{ message: "Unexpected 'super()'.", type: "CallExpression" }]
+            errors: [{ messageId: "unexpected", type: "CallExpression" }]
         },
 
         // inherit from non constructors.
         {
             code: "class A extends null { constructor() { super(); } }",
-            errors: [{ message: "Unexpected 'super()' because 'super' is not a constructor.", type: "CallExpression" }]
+            errors: [{ messageId: "badSuper", type: "CallExpression" }]
         },
         {
             code: "class A extends null { constructor() { } }",
-            errors: [{ message: "Expected to call 'super()'.", type: "MethodDefinition" }]
+            errors: [{ messageId: "missingAll", type: "MethodDefinition" }]
         },
         {
             code: "class A extends 100 { constructor() { super(); } }",
-            errors: [{ message: "Unexpected 'super()' because 'super' is not a constructor.", type: "CallExpression" }]
+            errors: [{ messageId: "badSuper", type: "CallExpression" }]
         },
         {
             code: "class A extends 'test' { constructor() { super(); } }",
-            errors: [{ message: "Unexpected 'super()' because 'super' is not a constructor.", type: "CallExpression" }]
+            errors: [{ messageId: "badSuper", type: "CallExpression" }]
         },
 
         // derived classes.
         {
             code: "class A extends B { constructor() { } }",
-            errors: [{ message: "Expected to call 'super()'.", type: "MethodDefinition" }]
+            errors: [{ messageId: "missingAll", type: "MethodDefinition" }]
         },
         {
             code: "class A extends B { constructor() { for (var a of b) super.foo(); } }",
-            errors: [{ message: "Expected to call 'super()'.", type: "MethodDefinition" }]
+            errors: [{ messageId: "missingAll", type: "MethodDefinition" }]
         },
 
         // nested execution scope.
         {
             code: "class A extends B { constructor() { function c() { super(); } } }",
-            errors: [{ message: "Expected to call 'super()'.", type: "MethodDefinition" }]
+            errors: [{ messageId: "missingAll", type: "MethodDefinition" }]
         },
         {
             code: "class A extends B { constructor() { var c = function() { super(); } } }",
-            errors: [{ message: "Expected to call 'super()'.", type: "MethodDefinition" }]
+            errors: [{ messageId: "missingAll", type: "MethodDefinition" }]
         },
         {
             code: "class A extends B { constructor() { var c = () => super(); } }",
-            errors: [{ message: "Expected to call 'super()'.", type: "MethodDefinition" }]
+            errors: [{ messageId: "missingAll", type: "MethodDefinition" }]
         },
         {
             code: "class A extends B { constructor() { class C extends D { constructor() { super(); } } } }",
-            errors: [{ message: "Expected to call 'super()'.", type: "MethodDefinition", column: 21 }]
+            errors: [{ messageId: "missingAll", type: "MethodDefinition", column: 21 }]
         },
         {
             code: "class A extends B { constructor() { var C = class extends D { constructor() { super(); } } } }",
-            errors: [{ message: "Expected to call 'super()'.", type: "MethodDefinition", column: 21 }]
+            errors: [{ messageId: "missingAll", type: "MethodDefinition", column: 21 }]
         },
         {
             code: "class A extends B { constructor() { super(); class C extends D { constructor() { } } } }",
-            errors: [{ message: "Expected to call 'super()'.", type: "MethodDefinition", column: 66 }]
+            errors: [{ messageId: "missingAll", type: "MethodDefinition", column: 66 }]
         },
         {
             code: "class A extends B { constructor() { super(); var C = class extends D { constructor() { } } } }",
-            errors: [{ message: "Expected to call 'super()'.", type: "MethodDefinition", column: 72 }]
+            errors: [{ messageId: "missingAll", type: "MethodDefinition", column: 72 }]
         },
 
         // lacked in some code path.
         {
             code: "class A extends B { constructor() { if (a) super(); } }",
-            errors: [{ message: "Lacked a call of 'super()' in some code paths.", type: "MethodDefinition" }]
+            errors: [{ messageId: "missingSome", type: "MethodDefinition" }]
         },
         {
             code: "class A extends B { constructor() { if (a); else super(); } }",
-            errors: [{ message: "Lacked a call of 'super()' in some code paths.", type: "MethodDefinition" }]
+            errors: [{ messageId: "missingSome", type: "MethodDefinition" }]
         },
         {
             code: "class A extends B { constructor() { a && super(); } }",
-            errors: [{ message: "Lacked a call of 'super()' in some code paths.", type: "MethodDefinition" }]
+            errors: [{ messageId: "missingSome", type: "MethodDefinition" }]
         },
         {
             code: "class A extends B { constructor() { switch (a) { case 0: super(); } } }",
-            errors: [{ message: "Lacked a call of 'super()' in some code paths.", type: "MethodDefinition" }]
+            errors: [{ messageId: "missingSome", type: "MethodDefinition" }]
         },
         {
             code: "class A extends B { constructor() { switch (a) { case 0: break; default: super(); } } }",
-            errors: [{ message: "Lacked a call of 'super()' in some code paths.", type: "MethodDefinition" }]
+            errors: [{ messageId: "missingSome", type: "MethodDefinition" }]
         },
         {
             code: "class A extends B { constructor() { try { super(); } catch (err) {} } }",
-            errors: [{ message: "Lacked a call of 'super()' in some code paths.", type: "MethodDefinition" }]
+            errors: [{ messageId: "missingSome", type: "MethodDefinition" }]
         },
         {
             code: "class A extends B { constructor() { try { a; } catch (err) { super(); } } }",
-            errors: [{ message: "Lacked a call of 'super()' in some code paths.", type: "MethodDefinition" }]
+            errors: [{ messageId: "missingSome", type: "MethodDefinition" }]
         },
         {
             code: "class A extends B { constructor() { if (a) return; super(); } }",
-            errors: [{ message: "Lacked a call of 'super()' in some code paths.", type: "MethodDefinition" }]
+            errors: [{ messageId: "missingSome", type: "MethodDefinition" }]
         },
 
         // duplicate.
         {
             code: "class A extends B { constructor() { super(); super(); } }",
-            errors: [{ message: "Unexpected duplicate 'super()'.", type: "CallExpression", column: 46 }]
+            errors: [{ messageId: "duplicate", type: "CallExpression", column: 46 }]
         },
         {
             code: "class A extends B { constructor() { super() || super(); } }",
-            errors: [{ message: "Unexpected duplicate 'super()'.", type: "CallExpression", column: 48 }]
+            errors: [{ messageId: "duplicate", type: "CallExpression", column: 48 }]
         },
         {
             code: "class A extends B { constructor() { if (a) super(); super(); } }",
-            errors: [{ message: "Unexpected duplicate 'super()'.", type: "CallExpression", column: 53 }]
+            errors: [{ messageId: "duplicate", type: "CallExpression", column: 53 }]
         },
         {
             code: "class A extends B { constructor() { switch (a) { case 0: super(); default: super(); } } }",
-            errors: [{ message: "Unexpected duplicate 'super()'.", type: "CallExpression", column: 76 }]
+            errors: [{ messageId: "duplicate", type: "CallExpression", column: 76 }]
         },
         {
             code: "class A extends B { constructor(a) { while (a) super(); } }",
             errors: [
-                { message: "Lacked a call of 'super()' in some code paths.", type: "MethodDefinition" },
-                { message: "Unexpected duplicate 'super()'.", type: "CallExpression", column: 48 }
+                { messageId: "missingSome", type: "MethodDefinition" },
+                { messageId: "duplicate", type: "CallExpression", column: 48 }
             ]
         },
 
         // ignores `super()` on unreachable paths.
         {
             code: "class A extends B { constructor() { return; super(); } }",
-            errors: [{ message: "Expected to call 'super()'.", type: "MethodDefinition" }]
+            errors: [{ messageId: "missingAll", type: "MethodDefinition" }]
         },
 
         // https://github.com/eslint/eslint/issues/8248
@@ -235,7 +235,7 @@ ruleTester.run("constructor-super", rule, {
                     for (a in b) for (c in d);
                 }
             }`,
-            errors: [{ message: "Expected to call 'super()'.", type: "MethodDefinition" }]
+            errors: [{ messageId: "missingAll", type: "MethodDefinition" }]
         }
     ]
 });
diff --git a/tests/lib/rules/curly.js b/tests/lib/rules/curly.js
index f9a04790d3b..028465fde99 100644
--- a/tests/lib/rules/curly.js
+++ b/tests/lib/rules/curly.js
@@ -219,7 +219,8 @@ ruleTester.run("curly", rule, {
             output: "if (foo) {bar()}",
             errors: [
                 {
-                    message: "Expected { after 'if' condition.",
+                    messageId: "missingCurlyAfterCondition",
+                    data: { name: "if" },
                     type: "IfStatement"
                 }
             ]
@@ -229,7 +230,8 @@ ruleTester.run("curly", rule, {
             output: "if (foo) { bar() } else {baz()}",
             errors: [
                 {
-                    message: "Expected { after 'else'.",
+                    messageId: "missingCurlyAfter",
+                    data: { name: "else" },
                     type: "IfStatement"
                 }
             ]
@@ -239,7 +241,8 @@ ruleTester.run("curly", rule, {
             output: "if (foo) { bar() } else if (faa) {baz()}",
             errors: [
                 {
-                    message: "Expected { after 'if' condition.",
+                    messageId: "missingCurlyAfterCondition",
+                    data: { name: "if" },
                     type: "IfStatement"
                 }
             ]
@@ -249,7 +252,8 @@ ruleTester.run("curly", rule, {
             output: "while (foo) {bar()}",
             errors: [
                 {
-                    message: "Expected { after 'while' condition.",
+                    messageId: "missingCurlyAfterCondition",
+                    data: { name: "while" },
                     type: "WhileStatement"
                 }
             ]
@@ -259,7 +263,8 @@ ruleTester.run("curly", rule, {
             output: "do {bar();} while (foo)",
             errors: [
                 {
-                    message: "Expected { after 'do'.",
+                    messageId: "missingCurlyAfter",
+                    data: { name: "do" },
                     type: "DoWhileStatement"
                 }
             ]
@@ -269,7 +274,8 @@ ruleTester.run("curly", rule, {
             output: "for (;foo;) {bar()}",
             errors: [
                 {
-                    message: "Expected { after 'for' condition.",
+                    messageId: "missingCurlyAfterCondition",
+                    data: { name: "for" },
                     type: "ForStatement"
                 }
             ]
@@ -279,7 +285,8 @@ ruleTester.run("curly", rule, {
             output: "for (var foo in bar) {console.log(foo)}",
             errors: [
                 {
-                    message: "Expected { after 'for-in'.",
+                    messageId: "missingCurlyAfter",
+                    data: { name: "for-in" },
                     type: "ForInStatement"
                 }
             ]
@@ -290,7 +297,8 @@ ruleTester.run("curly", rule, {
             parserOptions: { ecmaVersion: 6 },
             errors: [
                 {
-                    message: "Expected { after 'for-of'.",
+                    messageId: "missingCurlyAfter",
+                    data: { name: "for-of" },
                     type: "ForOfStatement"
                 }
             ]
@@ -301,7 +309,8 @@ ruleTester.run("curly", rule, {
             options: ["multi"],
             errors: [
                 {
-                    message: "Unnecessary { after 'for' condition.",
+                    messageId: "unexpectedCurlyAfterCondition",
+                    data: { name: "for" },
                     type: "ForStatement"
                 }
             ]
@@ -312,7 +321,8 @@ ruleTester.run("curly", rule, {
             options: ["multi"],
             errors: [
                 {
-                    message: "Unnecessary { after 'if' condition.",
+                    messageId: "unexpectedCurlyAfterCondition",
+                    data: { name: "if" },
                     type: "IfStatement"
                 }
             ]
@@ -323,7 +333,8 @@ ruleTester.run("curly", rule, {
             options: ["multi"],
             errors: [
                 {
-                    message: "Unnecessary { after 'while' condition.",
+                    messageId: "unexpectedCurlyAfterCondition",
+                    data: { name: "while" },
                     type: "WhileStatement"
                 }
             ]
@@ -334,7 +345,8 @@ ruleTester.run("curly", rule, {
             options: ["multi"],
             errors: [
                 {
-                    message: "Unnecessary { after 'else'.",
+                    messageId: "unexpectedCurlyAfter",
+                    data: { name: "else" },
                     type: "IfStatement"
                 }
             ]
@@ -345,7 +357,8 @@ ruleTester.run("curly", rule, {
             options: ["multi"],
             errors: [
                 {
-                    message: "Unnecessary { after 'if' condition.",
+                    messageId: "unexpectedCurlyAfterCondition",
+                    data: { name: "if" },
                     type: "IfStatement"
                 }
             ]
@@ -356,7 +369,8 @@ ruleTester.run("curly", rule, {
             options: ["multi"],
             errors: [
                 {
-                    message: "Unnecessary { after 'if' condition.",
+                    messageId: "unexpectedCurlyAfterCondition",
+                    data: { name: "if" },
                     type: "IfStatement"
                 }
             ]
@@ -391,7 +405,8 @@ ruleTester.run("curly", rule, {
             options: ["multi"],
             errors: [
                 {
-                    message: "Unnecessary { after 'else'.",
+                    messageId: "unexpectedCurlyAfter",
+                    data: { name: "else" },
                     type: "IfStatement",
                     line: 6,
                     column: 3
@@ -404,7 +419,8 @@ ruleTester.run("curly", rule, {
             options: ["multi"],
             errors: [
                 {
-                    message: "Unnecessary { after 'for-in'.",
+                    messageId: "unexpectedCurlyAfter",
+                    data: { name: "for-in" },
                     type: "ForInStatement"
                 }
             ]
@@ -416,7 +432,8 @@ ruleTester.run("curly", rule, {
             parserOptions: { ecmaVersion: 6 },
             errors: [
                 {
-                    message: "Unnecessary { after 'for-of'.",
+                    messageId: "unexpectedCurlyAfter",
+                    data: { name: "for-of" },
                     type: "ForOfStatement"
                 }
             ]
@@ -427,7 +444,8 @@ ruleTester.run("curly", rule, {
             options: ["multi-line"],
             errors: [
                 {
-                    message: "Expected { after 'if' condition.",
+                    messageId: "missingCurlyAfterCondition",
+                    data: { name: "if" },
                     type: "IfStatement"
                 }
             ]
@@ -438,7 +456,8 @@ ruleTester.run("curly", rule, {
             options: ["multi-line"],
             errors: [
                 {
-                    message: "Expected { after 'while' condition.",
+                    messageId: "missingCurlyAfterCondition",
+                    data: { name: "while" },
                     type: "WhileStatement"
                 }
             ]
@@ -449,7 +468,8 @@ ruleTester.run("curly", rule, {
             options: ["multi-line"],
             errors: [
                 {
-                    message: "Expected { after 'for' condition.",
+                    messageId: "missingCurlyAfterCondition",
+                    data: { name: "for" },
                     type: "ForStatement"
                 }
             ]
@@ -460,7 +480,8 @@ ruleTester.run("curly", rule, {
             options: ["multi-line"],
             errors: [
                 {
-                    message: "Expected { after 'while' condition.",
+                    messageId: "missingCurlyAfterCondition",
+                    data: { name: "while" },
                     type: "WhileStatement"
                 }
             ]
@@ -471,7 +492,8 @@ ruleTester.run("curly", rule, {
             options: ["multi-line"],
             errors: [
                 {
-                    message: "Expected { after 'if' condition.",
+                    messageId: "missingCurlyAfterCondition",
+                    data: { name: "if" },
                     type: "IfStatement"
                 }
             ]
@@ -482,7 +504,8 @@ ruleTester.run("curly", rule, {
             options: ["multi-line"],
             errors: [
                 {
-                    message: "Expected { after 'do'.",
+                    messageId: "missingCurlyAfter",
+                    data: { name: "do" },
                     type: "DoWhileStatement"
                 }
             ]
@@ -493,7 +516,8 @@ ruleTester.run("curly", rule, {
             options: ["multi-line"],
             errors: [
                 {
-                    message: "Expected { after 'for-in'.",
+                    messageId: "missingCurlyAfter",
+                    data: { name: "for-in" },
                     type: "ForInStatement"
                 }
             ]
@@ -504,7 +528,8 @@ ruleTester.run("curly", rule, {
             options: ["multi-line"],
             errors: [
                 {
-                    message: "Expected { after 'for-in'.",
+                    messageId: "missingCurlyAfter",
+                    data: { name: "for-in" },
                     type: "ForInStatement"
                 }
             ]
@@ -516,7 +541,8 @@ ruleTester.run("curly", rule, {
             parserOptions: { ecmaVersion: 6 },
             errors: [
                 {
-                    message: "Expected { after 'for-of'.",
+                    messageId: "missingCurlyAfter",
+                    data: { name: "for-of" },
                     type: "ForOfStatement"
                 }
             ]
@@ -528,7 +554,8 @@ ruleTester.run("curly", rule, {
             parserOptions: { ecmaVersion: 6 },
             errors: [
                 {
-                    message: "Expected { after 'for-of'.",
+                    messageId: "missingCurlyAfter",
+                    data: { name: "for-of" },
                     type: "ForOfStatement"
                 }
             ]
@@ -539,7 +566,8 @@ ruleTester.run("curly", rule, {
             options: ["multi-or-nest"],
             errors: [
                 {
-                    message: "Expected { after 'if' condition.",
+                    messageId: "missingCurlyAfterCondition",
+                    data: { name: "if" },
                     type: "IfStatement"
                 }
             ]
@@ -550,7 +578,8 @@ ruleTester.run("curly", rule, {
             options: ["multi-or-nest"],
             errors: [
                 {
-                    message: "Expected { after 'while' condition.",
+                    messageId: "missingCurlyAfterCondition",
+                    data: { name: "while" },
                     type: "WhileStatement"
                 }
             ]
@@ -561,7 +590,8 @@ ruleTester.run("curly", rule, {
             options: ["multi-or-nest"],
             errors: [
                 {
-                    message: "Unnecessary { after 'if' condition.",
+                    messageId: "unexpectedCurlyAfterCondition",
+                    data: { name: "if" },
                     type: "IfStatement"
                 }
             ]
@@ -572,7 +602,8 @@ ruleTester.run("curly", rule, {
             options: ["multi-or-nest"],
             errors: [
                 {
-                    message: "Unnecessary { after 'while' condition.",
+                    messageId: "unexpectedCurlyAfterCondition",
+                    data: { name: "while" },
                     type: "WhileStatement"
                 }
             ]
@@ -583,7 +614,8 @@ ruleTester.run("curly", rule, {
             options: ["multi-or-nest"],
             errors: [
                 {
-                    message: "Unnecessary { after 'for' condition.",
+                    messageId: "unexpectedCurlyAfterCondition",
+                    data: { name: "for" },
                     type: "ForStatement"
                 }
             ]
@@ -594,7 +626,8 @@ ruleTester.run("curly", rule, {
             options: ["multi-or-nest"],
             errors: [
                 {
-                    message: "Expected { after 'for-in'.",
+                    messageId: "missingCurlyAfter",
+                    data: { name: "for-in" },
                     type: "ForInStatement"
                 }
             ]
@@ -605,7 +638,8 @@ ruleTester.run("curly", rule, {
             options: ["multi-or-nest"],
             errors: [
                 {
-                    message: "Unnecessary { after 'for-in'.",
+                    messageId: "unexpectedCurlyAfter",
+                    data: { name: "for-in" },
                     type: "ForInStatement"
                 }
             ]
@@ -617,7 +651,8 @@ ruleTester.run("curly", rule, {
             parserOptions: { ecmaVersion: 6 },
             errors: [
                 {
-                    message: "Expected { after 'for-of'.",
+                    messageId: "missingCurlyAfter",
+                    data: { name: "for-of" },
                     type: "ForOfStatement"
                 }
             ]
@@ -629,7 +664,8 @@ ruleTester.run("curly", rule, {
             parserOptions: { ecmaVersion: 6 },
             errors: [
                 {
-                    message: "Unnecessary { after 'for-of'.",
+                    messageId: "unexpectedCurlyAfter",
+                    data: { name: "for-of" },
                     type: "ForOfStatement"
                 }
             ]
@@ -640,7 +676,8 @@ ruleTester.run("curly", rule, {
             options: ["multi", "consistent"],
             errors: [
                 {
-                    message: "Expected { after 'if' condition.",
+                    messageId: "missingCurlyAfterCondition",
+                    data: { name: "if" },
                     type: "IfStatement"
                 }
             ]
@@ -651,7 +688,8 @@ ruleTester.run("curly", rule, {
             options: ["multi", "consistent"],
             errors: [
                 {
-                    message: "Expected { after 'else'.",
+                    messageId: "missingCurlyAfter",
+                    data: { name: "else" },
                     type: "IfStatement"
                 }
             ]
@@ -662,7 +700,8 @@ ruleTester.run("curly", rule, {
             options: ["multi", "consistent"],
             errors: [
                 {
-                    message: "Unnecessary { after 'else'.",
+                    messageId: "unexpectedCurlyAfter",
+                    data: { name: "else" },
                     type: "IfStatement"
                 }
             ]
@@ -673,11 +712,13 @@ ruleTester.run("curly", rule, {
             options: ["multi", "consistent"],
             errors: [
                 {
-                    message: "Expected { after 'if' condition.",
+                    messageId: "missingCurlyAfterCondition",
+                    data: { name: "if" },
                     type: "IfStatement"
                 },
                 {
-                    message: "Expected { after 'if' condition.",
+                    messageId: "missingCurlyAfterCondition",
+                    data: { name: "if" },
                     type: "IfStatement"
                 }
             ]
@@ -688,7 +729,8 @@ ruleTester.run("curly", rule, {
             options: ["multi"],
             errors: [
                 {
-                    message: "Unnecessary { after 'do'.",
+                    messageId: "unexpectedCurlyAfter",
+                    data: { name: "do" },
                     type: "DoWhileStatement"
                 }
             ]
@@ -699,7 +741,8 @@ ruleTester.run("curly", rule, {
             options: ["multi"],
             errors: [
                 {
-                    message: "Unnecessary { after 'do'.",
+                    messageId: "unexpectedCurlyAfter",
+                    data: { name: "do" },
                     type: "DoWhileStatement"
                 }
             ]
@@ -710,7 +753,8 @@ ruleTester.run("curly", rule, {
             options: ["multi"],
             errors: [
                 {
-                    message: "Unnecessary { after 'if' condition.",
+                    messageId: "unexpectedCurlyAfterCondition",
+                    data: { name: "if" },
                     type: "IfStatement"
                 }
             ]
@@ -721,7 +765,8 @@ ruleTester.run("curly", rule, {
             options: ["multi"],
             errors: [
                 {
-                    message: "Unnecessary { after 'do'.",
+                    messageId: "unexpectedCurlyAfter",
+                    data: { name: "do" },
                     type: "DoWhileStatement"
                 }
             ]
@@ -732,44 +777,44 @@ ruleTester.run("curly", rule, {
             code: "if (foo) { bar }\n++baz;",
             output: null,
             options: ["multi"],
-            errors: [{ message: "Unnecessary { after 'if' condition.", type: "IfStatement" }]
+            errors: [{ messageId: "unexpectedCurlyAfterCondition", data: { name: "if" }, type: "IfStatement" }]
         },
         {
             code: "if (foo) { bar; }\n++baz;",
             output: "if (foo)  bar; \n++baz;",
             options: ["multi"],
-            errors: [{ message: "Unnecessary { after 'if' condition.", type: "IfStatement" }]
+            errors: [{ messageId: "unexpectedCurlyAfterCondition", data: { name: "if" }, type: "IfStatement" }]
         },
         {
             code: "if (foo) { bar++ }\nbaz;",
             output: null,
             options: ["multi"],
-            errors: [{ message: "Unnecessary { after 'if' condition.", type: "IfStatement" }]
+            errors: [{ messageId: "unexpectedCurlyAfterCondition", data: { name: "if" }, type: "IfStatement" }]
         },
         {
             code: "if (foo) { bar }\n[1, 2, 3].map(foo);",
             output: null,
             options: ["multi"],
-            errors: [{ message: "Unnecessary { after 'if' condition.", type: "IfStatement" }]
+            errors: [{ messageId: "unexpectedCurlyAfterCondition", data: { name: "if" }, type: "IfStatement" }]
         },
         {
             code: "if (foo) { bar }\n(1).toString();",
             output: null,
             options: ["multi"],
-            errors: [{ message: "Unnecessary { after 'if' condition.", type: "IfStatement" }]
+            errors: [{ messageId: "unexpectedCurlyAfterCondition", data: { name: "if" }, type: "IfStatement" }]
         },
         {
             code: "if (foo) { bar }\n/regex/.test('foo');",
             output: null,
             options: ["multi"],
             parserOptions: { ecmaVersion: 6 },
-            errors: [{ message: "Unnecessary { after 'if' condition.", type: "IfStatement" }]
+            errors: [{ messageId: "unexpectedCurlyAfterCondition", data: { name: "if" }, type: "IfStatement" }]
         },
         {
             code: "if (foo) { bar }\nBaz();",
             output: "if (foo)  bar \nBaz();",
             options: ["multi"],
-            errors: [{ message: "Unnecessary { after 'if' condition.", type: "IfStatement" }]
+            errors: [{ messageId: "unexpectedCurlyAfterCondition", data: { name: "if" }, type: "IfStatement" }]
         },
         {
             code:
@@ -787,39 +832,39 @@ ruleTester.run("curly", rule, {
             "  }\n" +
             " else e();",
             options: ["multi"],
-            errors: [{ message: "Unnecessary { after 'if' condition.", type: "IfStatement" }]
+            errors: [{ messageId: "unexpectedCurlyAfterCondition", data: { name: "if" }, type: "IfStatement" }]
         },
         {
             code: "if (foo) { while (bar) {} } else {}",
             output: "if (foo)  while (bar) {}  else {}",
             options: ["multi"],
-            errors: [{ message: "Unnecessary { after 'if' condition.", type: "IfStatement" }]
+            errors: [{ messageId: "unexpectedCurlyAfterCondition", data: { name: "if" }, type: "IfStatement" }]
         },
         {
             code: "if (foo) { var foo = () => {} } else {}",
             output: null,
             options: ["multi"],
             parserOptions: { ecmaVersion: 6 },
-            errors: [{ message: "Unnecessary { after 'if' condition.", type: "IfStatement" }]
+            errors: [{ messageId: "unexpectedCurlyAfterCondition", data: { name: "if" }, type: "IfStatement" }]
         },
         {
             code: "if (foo) { var foo = function() {} } else {}",
             output: null,
             options: ["multi"],
-            errors: [{ message: "Unnecessary { after 'if' condition.", type: "IfStatement" }]
+            errors: [{ messageId: "unexpectedCurlyAfterCondition", data: { name: "if" }, type: "IfStatement" }]
         },
         {
             code: "if (foo) { var foo = function*() {} } else {}",
             output: null,
             options: ["multi"],
             parserOptions: { ecmaVersion: 6 },
-            errors: [{ message: "Unnecessary { after 'if' condition.", type: "IfStatement" }]
+            errors: [{ messageId: "unexpectedCurlyAfterCondition", data: { name: "if" }, type: "IfStatement" }]
         },
         {
             code: "if (true)\nfoo()\n;[1, 2, 3].bar()",
             output: "if (true)\n{foo()\n;}[1, 2, 3].bar()",
             options: ["multi-line"],
-            errors: [{ message: "Expected { after 'if' condition.", type: "IfStatement" }]
+            errors: [{ messageId: "missingCurlyAfterCondition", data: { name: "if" }, type: "IfStatement" }]
         }
     ]
 });
diff --git a/tests/lib/rules/default-case.js b/tests/lib/rules/default-case.js
index 1ade2e63da5..a0e21aeca23 100644
--- a/tests/lib/rules/default-case.js
+++ b/tests/lib/rules/default-case.js
@@ -63,21 +63,21 @@ ruleTester.run("default-case", rule, {
         {
             code: "switch (a) { case 1: break; }",
             errors: [{
-                message: "Expected a default case.",
+                messageId: "missingDefaultCase",
                 type: "SwitchStatement"
             }]
         },
         {
             code: "switch (a) { \n // no default \n case 1: break;  }",
             errors: [{
-                message: "Expected a default case.",
+                messageId: "missingDefaultCase",
                 type: "SwitchStatement"
             }]
         },
         {
             code: "switch (a) { case 1: break; \n // no default \n // nope \n  }",
             errors: [{
-                message: "Expected a default case.",
+                messageId: "missingDefaultCase",
                 type: "SwitchStatement"
             }]
         },
@@ -87,7 +87,7 @@ ruleTester.run("default-case", rule, {
                 commentPattern: "skipped default case"
             }],
             errors: [{
-                message: "Expected a default case.",
+                messageId: "missingDefaultCase",
                 type: "SwitchStatement"
             }]
         },
@@ -97,7 +97,7 @@ ruleTester.run("default-case", rule, {
                 commentPattern: "default omitted"
             }],
             errors: [{
-                message: "Expected a default case.",
+                messageId: "missingDefaultCase",
                 type: "SwitchStatement"
             }]
         },
@@ -107,7 +107,7 @@ ruleTester.run("default-case", rule, {
                 commentPattern: ".?"
             }],
             errors: [{
-                message: "Expected a default case.",
+                messageId: "missingDefaultCase",
                 type: "SwitchStatement"
             }]
         }
diff --git a/tests/lib/rules/dot-location.js b/tests/lib/rules/dot-location.js
index 64e798bc8ee..381afc55966 100644
--- a/tests/lib/rules/dot-location.js
+++ b/tests/lib/rules/dot-location.js
@@ -44,43 +44,43 @@ ruleTester.run("dot-location", rule, {
             code: "obj\n.property",
             output: "obj.\nproperty",
             options: ["object"],
-            errors: [{ message: "Expected dot to be on same line as object.", type: "MemberExpression", line: 2, column: 1 }]
+            errors: [{ messageId: "expectedDotAfterObject", type: "MemberExpression", line: 2, column: 1 }]
         },
         {
             code: "obj.\nproperty",
             output: "obj\n.property",
             options: ["property"],
-            errors: [{ message: "Expected dot to be on same line as property.", type: "MemberExpression", line: 1, column: 4 }]
+            errors: [{ messageId: "expectedDotBeforeProperty", type: "MemberExpression", line: 1, column: 4 }]
         },
         {
             code: "(obj).\nproperty",
             output: "(obj)\n.property",
             options: ["property"],
-            errors: [{ message: "Expected dot to be on same line as property.", type: "MemberExpression", line: 1, column: 6 }]
+            errors: [{ messageId: "expectedDotBeforeProperty", type: "MemberExpression", line: 1, column: 6 }]
         },
         {
             code: "5\n.toExponential()",
             output: "5 .\ntoExponential()",
             options: ["object"],
-            errors: [{ message: "Expected dot to be on same line as object.", type: "MemberExpression", line: 2, column: 1 }]
+            errors: [{ messageId: "expectedDotAfterObject", type: "MemberExpression", line: 2, column: 1 }]
         },
         {
             code: "-5\n.toExponential()",
             output: "-5 .\ntoExponential()",
             options: ["object"],
-            errors: [{ message: "Expected dot to be on same line as object.", type: "MemberExpression", line: 2, column: 1 }]
+            errors: [{ messageId: "expectedDotAfterObject", type: "MemberExpression", line: 2, column: 1 }]
         },
         {
             code: "foo /* a */ . /* b */ \n /* c */ bar",
             output: "foo /* a */  /* b */ \n /* c */ .bar",
             options: ["property"],
-            errors: [{ message: "Expected dot to be on same line as property.", type: "MemberExpression", line: 1, column: 13 }]
+            errors: [{ messageId: "expectedDotBeforeProperty", type: "MemberExpression", line: 1, column: 13 }]
         },
         {
             code: "foo /* a */ \n /* b */ . /* c */ bar",
             output: "foo. /* a */ \n /* b */  /* c */ bar",
             options: ["object"],
-            errors: [{ message: "Expected dot to be on same line as object.", type: "MemberExpression", line: 2, column: 10 }]
+            errors: [{ messageId: "expectedDotAfterObject", type: "MemberExpression", line: 2, column: 10 }]
         }
     ]
 });
diff --git a/tests/lib/rules/dot-notation.js b/tests/lib/rules/dot-notation.js
index 9d1be6a8a37..1261fb8853e 100644
--- a/tests/lib/rules/dot-notation.js
+++ b/tests/lib/rules/dot-notation.js
@@ -18,6 +18,16 @@ const rule = require("../../../lib/rules/dot-notation"),
 
 const ruleTester = new RuleTester();
 
+/**
+ * Quote a string in "double quotes" because it’s painful
+ * with a double-quoted string literal
+ * @param   {string} str The string to quote
+ * @returns {string}     `"${str}"`
+ */
+function q(str) {
+    return `"${str}"`;
+}
+
 ruleTester.run("dot-notation", rule, {
     valid: [
         "a.b;",
@@ -54,45 +64,45 @@ ruleTester.run("dot-notation", rule, {
             code: "a.true;",
             output: "a[\"true\"];",
             options: [{ allowKeywords: false }],
-            errors: [{ message: ".true is a syntax error." }]
+            errors: [{ messageId: "useBrackets", data: { key: "true" } }]
         },
         {
             code: "a['true'];",
             output: "a.true;",
-            errors: [{ message: "[\"true\"] is better written in dot notation." }]
+            errors: [{ messageId: "useDot", data: { key: q("true") } }]
         },
         {
             code: "a[`time`];",
             output: "a.time;",
             parserOptions: { ecmaVersion: 6 },
-            errors: [{ message: "[`time`] is better written in dot notation." }]
+            errors: [{ messageId: "useDot", data: { key: "`time`" } }]
         },
         {
             code: "a[null];",
             output: "a.null;",
-            errors: [{ message: "[null] is better written in dot notation." }]
+            errors: [{ messageId: "useDot", data: { key: "null" } }]
         },
         {
             code: "a['b'];",
             output: "a.b;",
-            errors: [{ message: "[\"b\"] is better written in dot notation." }]
+            errors: [{ messageId: "useDot", data: { key: q("b") } }]
         },
         {
             code: "a.b['c'];",
             output: "a.b.c;",
-            errors: [{ message: "[\"c\"] is better written in dot notation." }]
+            errors: [{ messageId: "useDot", data: { key: q("c") } }]
         },
         {
             code: "a['_dangle'];",
             output: "a._dangle;",
             options: [{ allowPattern: "^[a-z]+(_[a-z]+)+$" }],
-            errors: [{ message: "[\"_dangle\"] is better written in dot notation." }]
+            errors: [{ messageId: "useDot", data: { key: q("_dangle") } }]
         },
         {
             code: "a['SHOUT_CASE'];",
             output: "a.SHOUT_CASE;",
             options: [{ allowPattern: "^[a-z]+(_[a-z]+)+$" }],
-            errors: [{ message: "[\"SHOUT_CASE\"] is better written in dot notation." }]
+            errors: [{ messageId: "useDot", data: { key: q("SHOUT_CASE") } }]
         },
         {
             code:
@@ -102,7 +112,8 @@ ruleTester.run("dot-notation", rule, {
                 "a\n" +
                 "  .SHOUT_CASE;",
             errors: [{
-                message: "[\"SHOUT_CASE\"] is better written in dot notation.",
+                messageId: "useDot",
+                data: { key: q("SHOUT_CASE") },
                 line: 2,
                 column: 4
             }]
@@ -122,12 +133,14 @@ ruleTester.run("dot-notation", rule, {
             "    .catch(function(){});",
             errors: [
                 {
-                    message: "[\"catch\"] is better written in dot notation.",
+                    messageId: "useDot",
+                    data: { key: q("catch") },
                     line: 3,
                     column: 6
                 },
                 {
-                    message: "[\"catch\"] is better written in dot notation.",
+                    messageId: "useDot",
+                    data: { key: q("catch") },
                     line: 5,
                     column: 6
                 }
@@ -141,59 +154,59 @@ ruleTester.run("dot-notation", rule, {
             "foo\n" +
             "  [\"while\"];",
             options: [{ allowKeywords: false }],
-            errors: [{ message: ".while is a syntax error." }]
+            errors: [{ messageId: "useBrackets", data: { key: "while" } }]
         },
         {
             code: "foo[ /* comment */ 'bar' ]",
             output: null, // Not fixed due to comment
-            errors: [{ message: "[\"bar\"] is better written in dot notation." }]
+            errors: [{ messageId: "useDot", data: { key: q("bar") } }]
         },
         {
             code: "foo[ 'bar' /* comment */ ]",
             output: null, // Not fixed due to comment
-            errors: [{ message: "[\"bar\"] is better written in dot notation." }]
+            errors: [{ messageId: "useDot", data: { key: q("bar") } }]
         },
         {
             code: "foo[    'bar'    ];",
             output: "foo.bar;",
-            errors: [{ message: "[\"bar\"] is better written in dot notation." }]
+            errors: [{ messageId: "useDot", data: { key: q("bar") } }]
         },
         {
             code: "foo. /* comment */ while",
             output: null, // Not fixed due to comment
             options: [{ allowKeywords: false }],
-            errors: [{ message: ".while is a syntax error." }]
+            errors: [{ messageId: "useBrackets", data: { key: "while" } }]
         },
         {
             code: "foo[('bar')]",
             output: "foo.bar",
-            errors: [{ message: "[\"bar\"] is better written in dot notation." }]
+            errors: [{ messageId: "useDot", data: { key: q("bar") } }]
         },
         {
             code: "foo[(null)]",
             output: "foo.null",
-            errors: [{ message: "[null] is better written in dot notation." }]
+            errors: [{ messageId: "useDot", data: { key: "null" } }]
         },
         {
             code: "(foo)['bar']",
             output: "(foo).bar",
-            errors: [{ message: "[\"bar\"] is better written in dot notation." }]
+            errors: [{ messageId: "useDot", data: { key: q("bar") } }]
         },
         {
             code: "1['toString']",
             output: "1 .toString",
-            errors: [{ message: "[\"toString\"] is better written in dot notation." }]
+            errors: [{ messageId: "useDot", data: { key: q("toString") } }]
         },
         {
             code: "foo['bar']instanceof baz",
             output: "foo.bar instanceof baz",
-            errors: [{ message: "[\"bar\"] is better written in dot notation." }]
+            errors: [{ messageId: "useDot", data: { key: q("bar") } }]
         },
         {
             code: "let.if()",
             output: null, // `let["if"]()` is a syntax error because `let[` indicates a destructuring variable declaration
             options: [{ allowKeywords: false }],
-            errors: [{ message: ".if is a syntax error." }]
+            errors: [{ messageId: "useBrackets", data: { key: "if" } }]
         }
     ]
 });
diff --git a/tests/lib/rules/eol-last.js b/tests/lib/rules/eol-last.js
index fdc9e5d99c8..b5e1e54685b 100644
--- a/tests/lib/rules/eol-last.js
+++ b/tests/lib/rules/eol-last.js
@@ -55,48 +55,48 @@ ruleTester.run("eol-last", rule, {
         {
             code: "var a = 123;",
             output: "var a = 123;\n",
-            errors: [{ message: "Newline required at end of file but not found.", type: "Program" }]
+            errors: [{ messageId: "missing", type: "Program" }]
         },
         {
             code: "var a = 123;\n   ",
             output: "var a = 123;\n   \n",
-            errors: [{ message: "Newline required at end of file but not found.", type: "Program" }]
+            errors: [{ messageId: "missing", type: "Program" }]
         },
         {
             code: "var a = 123;\n",
             output: "var a = 123;",
             options: ["never"],
-            errors: [{ message: "Newline not allowed at end of file.", type: "Program" }]
+            errors: [{ messageId: "unexpected", type: "Program" }]
         },
         {
             code: "var a = 123;\r\n",
             output: "var a = 123;",
             options: ["never"],
-            errors: [{ message: "Newline not allowed at end of file.", type: "Program" }]
+            errors: [{ messageId: "unexpected", type: "Program" }]
         },
         {
             code: "var a = 123;\r\n\r\n",
             output: "var a = 123;",
             options: ["never"],
-            errors: [{ message: "Newline not allowed at end of file.", type: "Program" }]
+            errors: [{ messageId: "unexpected", type: "Program" }]
         },
         {
             code: "var a = 123;\nvar b = 456;\n",
             output: "var a = 123;\nvar b = 456;",
             options: ["never"],
-            errors: [{ message: "Newline not allowed at end of file.", type: "Program" }]
+            errors: [{ messageId: "unexpected", type: "Program" }]
         },
         {
             code: "var a = 123;\r\nvar b = 456;\r\n",
             output: "var a = 123;\r\nvar b = 456;",
             options: ["never"],
-            errors: [{ message: "Newline not allowed at end of file.", type: "Program" }]
+            errors: [{ messageId: "unexpected", type: "Program" }]
         },
         {
             code: "var a = 123;\n\n",
             output: "var a = 123;",
             options: ["never"],
-            errors: [{ message: "Newline not allowed at end of file.", type: "Program" }]
+            errors: [{ messageId: "unexpected", type: "Program" }]
         },
 
         // Deprecated: `"unix"` parameter
@@ -104,13 +104,13 @@ ruleTester.run("eol-last", rule, {
             code: "var a = 123;",
             output: "var a = 123;\n",
             options: ["unix"],
-            errors: [{ message: "Newline required at end of file but not found.", type: "Program" }]
+            errors: [{ messageId: "missing", type: "Program" }]
         },
         {
             code: "var a = 123;\n   ",
             output: "var a = 123;\n   \n",
             options: ["unix"],
-            errors: [{ message: "Newline required at end of file but not found.", type: "Program" }]
+            errors: [{ messageId: "missing", type: "Program" }]
         },
 
         // Deprecated: `"windows"` parameter
@@ -118,13 +118,13 @@ ruleTester.run("eol-last", rule, {
             code: "var a = 123;",
             output: "var a = 123;\r\n",
             options: ["windows"],
-            errors: [{ message: "Newline required at end of file but not found.", type: "Program" }]
+            errors: [{ messageId: "missing", type: "Program" }]
         },
         {
             code: "var a = 123;\r\n   ",
             output: "var a = 123;\r\n   \r\n",
             options: ["windows"],
-            errors: [{ message: "Newline required at end of file but not found.", type: "Program" }]
+            errors: [{ messageId: "missing", type: "Program" }]
         }
     ]
 });
diff --git a/tests/lib/rules/eqeqeq.js b/tests/lib/rules/eqeqeq.js
index da504839508..cf565363f45 100644
--- a/tests/lib/rules/eqeqeq.js
+++ b/tests/lib/rules/eqeqeq.js
@@ -18,6 +18,11 @@ const rule = require("../../../lib/rules/eqeqeq"),
 
 const ruleTester = new RuleTester();
 
+const wantedEqEqEq = { expectedOperator: "===", actualOperator: "==" };
+const wantedNotEqEq = { expectedOperator: "!==", actualOperator: "!=" };
+const wantedEqEq = { expectedOperator: "==", actualOperator: "===" };
+const wantedNotEq = { expectedOperator: "!=", actualOperator: "!==" };
+
 ruleTester.run("eqeqeq", rule, {
     valid: [
         "a === b",
@@ -48,44 +53,56 @@ ruleTester.run("eqeqeq", rule, {
         { code: "foo === /abc/u", options: ["always", { null: "never" }], parserOptions: { ecmaVersion: 6 } }
     ],
     invalid: [
-        { code: "a == b", errors: [{ message: "Expected '===' and instead saw '=='.", type: "BinaryExpression" }] },
-        { code: "a != b", errors: [{ message: "Expected '!==' and instead saw '!='.", type: "BinaryExpression" }] },
-        { code: "typeof a == 'number'", output: "typeof a === 'number'", errors: [{ message: "Expected '===' and instead saw '=='.", type: "BinaryExpression" }] },
-        { code: "typeof a == 'number'", output: "typeof a === 'number'", options: ["always"], errors: [{ message: "Expected '===' and instead saw '=='.", type: "BinaryExpression" }] },
-        { code: "'string' != typeof a", output: "'string' !== typeof a", errors: [{ message: "Expected '!==' and instead saw '!='.", type: "BinaryExpression" }] },
-        { code: "true == true", output: "true === true", errors: [{ message: "Expected '===' and instead saw '=='.", type: "BinaryExpression" }] },
-        { code: "2 == 3", output: "2 === 3", errors: [{ message: "Expected '===' and instead saw '=='.", type: "BinaryExpression" }] },
-        { code: "2 == 3", output: "2 === 3", options: ["always"], errors: [{ message: "Expected '===' and instead saw '=='.", type: "BinaryExpression" }] },
-        { code: "'hello' != 'world'", output: "'hello' !== 'world'", errors: [{ message: "Expected '!==' and instead saw '!='.", type: "BinaryExpression" }] },
-        { code: "'hello' != 'world'", output: "'hello' !== 'world'", options: ["always"], errors: [{ message: "Expected '!==' and instead saw '!='.", type: "BinaryExpression" }] },
-        { code: "a == null", errors: [{ message: "Expected '===' and instead saw '=='.", type: "BinaryExpression" }] },
-        { code: "a == null", options: ["always"], errors: [{ message: "Expected '===' and instead saw '=='.", type: "BinaryExpression" }] },
-        { code: "null != a", errors: [{ message: "Expected '!==' and instead saw '!='.", type: "BinaryExpression" }] },
-        { code: "true == 1", options: ["smart"], errors: [{ message: "Expected '===' and instead saw '=='.", type: "BinaryExpression" }] },
-        { code: "0 != '1'", options: ["smart"], errors: [{ message: "Expected '!==' and instead saw '!='.", type: "BinaryExpression" }] },
-        { code: "'wee' == /wee/", options: ["smart"], errors: [{ message: "Expected '===' and instead saw '=='.", type: "BinaryExpression" }] },
-        { code: "typeof a == 'number'", output: "typeof a === 'number'", options: ["allow-null"], errors: [{ message: "Expected '===' and instead saw '=='.", type: "BinaryExpression" }] },
-        { code: "'string' != typeof a", output: "'string' !== typeof a", options: ["allow-null"], errors: [{ message: "Expected '!==' and instead saw '!='.", type: "BinaryExpression" }] },
-        { code: "'hello' != 'world'", output: "'hello' !== 'world'", options: ["allow-null"], errors: [{ message: "Expected '!==' and instead saw '!='.", type: "BinaryExpression" }] },
-        { code: "2 == 3", output: "2 === 3", options: ["allow-null"], errors: [{ message: "Expected '===' and instead saw '=='.", type: "BinaryExpression" }] },
-        { code: "true == true", output: "true === true", options: ["allow-null"], errors: [{ message: "Expected '===' and instead saw '=='.", type: "BinaryExpression" }] },
-        { code: "true == null", options: ["always", { null: "always" }], errors: [{ message: "Expected '===' and instead saw '=='.", type: "BinaryExpression" }] },
-        { code: "true != null", options: ["always", { null: "always" }], errors: [{ message: "Expected '!==' and instead saw '!='.", type: "BinaryExpression" }] },
-        { code: "null == null", output: "null === null", options: ["always", { null: "always" }], errors: [{ message: "Expected '===' and instead saw '=='.", type: "BinaryExpression" }] },
-        { code: "null != null", output: "null !== null", options: ["always", { null: "always" }], errors: [{ message: "Expected '!==' and instead saw '!='.", type: "BinaryExpression" }] },
-        { code: "true === null", options: ["always", { null: "never" }], errors: [{ message: "Expected '==' and instead saw '==='.", type: "BinaryExpression" }] },
-        { code: "true !== null", options: ["always", { null: "never" }], errors: [{ message: "Expected '!=' and instead saw '!=='.", type: "BinaryExpression" }] },
-        { code: "null === null", output: "null == null", options: ["always", { null: "never" }], errors: [{ message: "Expected '==' and instead saw '==='.", type: "BinaryExpression" }] },
-        { code: "null !== null", output: "null != null", options: ["always", { null: "never" }], errors: [{ message: "Expected '!=' and instead saw '!=='.", type: "BinaryExpression" }] },
-        { code: "a\n==\nb", errors: [{ message: "Expected '===' and instead saw '=='.", type: "BinaryExpression", line: 2 }] },
-        { code: "(a) == b", errors: [{ message: "Expected '===' and instead saw '=='.", type: "BinaryExpression", line: 1 }] },
-        { code: "(a) != b", errors: [{ message: "Expected '!==' and instead saw '!='.", type: "BinaryExpression", line: 1 }] },
-        { code: "a == (b)", errors: [{ message: "Expected '===' and instead saw '=='.", type: "BinaryExpression", line: 1 }] },
-        { code: "a != (b)", errors: [{ message: "Expected '!==' and instead saw '!='.", type: "BinaryExpression", line: 1 }] },
-        { code: "(a) == (b)", errors: [{ message: "Expected '===' and instead saw '=='.", type: "BinaryExpression", line: 1 }] },
-        { code: "(a) != (b)", errors: [{ message: "Expected '!==' and instead saw '!='.", type: "BinaryExpression", line: 1 }] },
-        { code: "(a == b) == (c)", errors: [{ message: "Expected '===' and instead saw '=='.", type: "BinaryExpression", line: 1 }, { message: "Expected '===' and instead saw '=='.", type: "BinaryExpression", line: 1 }] },
-        { code: "(a != b) != (c)", errors: [{ message: "Expected '!==' and instead saw '!='.", type: "BinaryExpression", line: 1 }, { message: "Expected '!==' and instead saw '!='.", type: "BinaryExpression", line: 1 }] }
+        { code: "a == b", errors: [{ messageId: "unexpected", data: wantedEqEqEq, type: "BinaryExpression" }] },
+        { code: "a != b", errors: [{ messageId: "unexpected", data: wantedNotEqEq, type: "BinaryExpression" }] },
+        { code: "typeof a == 'number'", output: "typeof a === 'number'", errors: [{ messageId: "unexpected", data: wantedEqEqEq, type: "BinaryExpression" }] },
+        { code: "typeof a == 'number'", output: "typeof a === 'number'", options: ["always"], errors: [{ messageId: "unexpected", data: wantedEqEqEq, type: "BinaryExpression" }] },
+        { code: "'string' != typeof a", output: "'string' !== typeof a", errors: [{ messageId: "unexpected", data: wantedNotEqEq, type: "BinaryExpression" }] },
+        { code: "true == true", output: "true === true", errors: [{ messageId: "unexpected", data: wantedEqEqEq, type: "BinaryExpression" }] },
+        { code: "2 == 3", output: "2 === 3", errors: [{ messageId: "unexpected", data: wantedEqEqEq, type: "BinaryExpression" }] },
+        { code: "2 == 3", output: "2 === 3", options: ["always"], errors: [{ messageId: "unexpected", data: wantedEqEqEq, type: "BinaryExpression" }] },
+        { code: "'hello' != 'world'", output: "'hello' !== 'world'", errors: [{ messageId: "unexpected", data: wantedNotEqEq, type: "BinaryExpression" }] },
+        { code: "'hello' != 'world'", output: "'hello' !== 'world'", options: ["always"], errors: [{ messageId: "unexpected", data: wantedNotEqEq, type: "BinaryExpression" }] },
+        { code: "a == null", errors: [{ messageId: "unexpected", data: wantedEqEqEq, type: "BinaryExpression" }] },
+        { code: "a == null", options: ["always"], errors: [{ messageId: "unexpected", data: wantedEqEqEq, type: "BinaryExpression" }] },
+        { code: "null != a", errors: [{ messageId: "unexpected", data: wantedNotEqEq, type: "BinaryExpression" }] },
+        { code: "true == 1", options: ["smart"], errors: [{ messageId: "unexpected", data: wantedEqEqEq, type: "BinaryExpression" }] },
+        { code: "0 != '1'", options: ["smart"], errors: [{ messageId: "unexpected", data: wantedNotEqEq, type: "BinaryExpression" }] },
+        { code: "'wee' == /wee/", options: ["smart"], errors: [{ messageId: "unexpected", data: wantedEqEqEq, type: "BinaryExpression" }] },
+        { code: "typeof a == 'number'", output: "typeof a === 'number'", options: ["allow-null"], errors: [{ messageId: "unexpected", data: wantedEqEqEq, type: "BinaryExpression" }] },
+        { code: "'string' != typeof a", output: "'string' !== typeof a", options: ["allow-null"], errors: [{ messageId: "unexpected", data: wantedNotEqEq, type: "BinaryExpression" }] },
+        { code: "'hello' != 'world'", output: "'hello' !== 'world'", options: ["allow-null"], errors: [{ messageId: "unexpected", data: wantedNotEqEq, type: "BinaryExpression" }] },
+        { code: "2 == 3", output: "2 === 3", options: ["allow-null"], errors: [{ messageId: "unexpected", data: wantedEqEqEq, type: "BinaryExpression" }] },
+        { code: "true == true", output: "true === true", options: ["allow-null"], errors: [{ messageId: "unexpected", data: wantedEqEqEq, type: "BinaryExpression" }] },
+        { code: "true == null", options: ["always", { null: "always" }], errors: [{ messageId: "unexpected", data: wantedEqEqEq, type: "BinaryExpression" }] },
+        { code: "true != null", options: ["always", { null: "always" }], errors: [{ messageId: "unexpected", data: wantedNotEqEq, type: "BinaryExpression" }] },
+        { code: "null == null", output: "null === null", options: ["always", { null: "always" }], errors: [{ messageId: "unexpected", data: wantedEqEqEq, type: "BinaryExpression" }] },
+        { code: "null != null", output: "null !== null", options: ["always", { null: "always" }], errors: [{ messageId: "unexpected", data: wantedNotEqEq, type: "BinaryExpression" }] },
+        { code: "true === null", options: ["always", { null: "never" }], errors: [{ messageId: "unexpected", data: wantedEqEq, type: "BinaryExpression" }] },
+        { code: "true !== null", options: ["always", { null: "never" }], errors: [{ messageId: "unexpected", data: wantedNotEq, type: "BinaryExpression" }] },
+        { code: "null === null", output: "null == null", options: ["always", { null: "never" }], errors: [{ messageId: "unexpected", data: wantedEqEq, type: "BinaryExpression" }] },
+        { code: "null !== null", output: "null != null", options: ["always", { null: "never" }], errors: [{ messageId: "unexpected", data: wantedNotEq, type: "BinaryExpression" }] },
+        { code: "a\n==\nb", errors: [{ messageId: "unexpected", data: wantedEqEqEq, type: "BinaryExpression", line: 2 }] },
+        { code: "(a) == b", errors: [{ messageId: "unexpected", data: wantedEqEqEq, type: "BinaryExpression", line: 1 }] },
+        { code: "(a) != b", errors: [{ messageId: "unexpected", data: wantedNotEqEq, type: "BinaryExpression", line: 1 }] },
+        { code: "a == (b)", errors: [{ messageId: "unexpected", data: wantedEqEqEq, type: "BinaryExpression", line: 1 }] },
+        { code: "a != (b)", errors: [{ messageId: "unexpected", data: wantedNotEqEq, type: "BinaryExpression", line: 1 }] },
+        { code: "(a) == (b)", errors: [{ messageId: "unexpected", data: wantedEqEqEq, type: "BinaryExpression", line: 1 }] },
+        { code: "(a) != (b)", errors: [{ messageId: "unexpected", data: wantedNotEqEq, type: "BinaryExpression", line: 1 }] },
+        {
+            code: "(a == b) == (c)",
+            errors: [
+                { messageId: "unexpected", data: wantedEqEqEq, type: "BinaryExpression", line: 1 },
+                { messageId: "unexpected", data: wantedEqEqEq, type: "BinaryExpression", line: 1 }
+            ]
+        },
+        {
+            code: "(a != b) != (c)",
+            errors: [
+                { messageId: "unexpected", data: wantedNotEqEq, type: "BinaryExpression", line: 1 },
+                { messageId: "unexpected", data: wantedNotEqEq, type: "BinaryExpression", line: 1 }
+            ]
+        }
 
     // If no output is provided, assert that no output is produced.
     ].map(invalidCase => Object.assign({ output: null }, invalidCase))
diff --git a/tests/lib/rules/no-alert.js b/tests/lib/rules/no-alert.js
index 03f4a2d07c5..0f8de5a4cac 100644
--- a/tests/lib/rules/no-alert.js
+++ b/tests/lib/rules/no-alert.js
@@ -39,71 +39,71 @@ ruleTester.run("no-alert", rule, {
     invalid: [
         {
             code: "alert(foo)",
-            errors: [{ message: "Unexpected alert.", type: "CallExpression", line: 1, column: 1 }]
+            errors: [{ messageId: "unexpected", data: { name: "alert" }, type: "CallExpression", line: 1, column: 1 }]
         },
         {
             code: "window.alert(foo)",
-            errors: [{ message: "Unexpected alert.", type: "CallExpression", line: 1, column: 1 }]
+            errors: [{ messageId: "unexpected", data: { name: "alert" }, type: "CallExpression", line: 1, column: 1 }]
         },
         {
             code: "window['alert'](foo)",
-            errors: [{ message: "Unexpected alert.", type: "CallExpression", line: 1, column: 1 }]
+            errors: [{ messageId: "unexpected", data: { name: "alert" }, type: "CallExpression", line: 1, column: 1 }]
         },
         {
             code: "confirm(foo)",
-            errors: [{ message: "Unexpected confirm.", type: "CallExpression", line: 1, column: 1 }]
+            errors: [{ messageId: "unexpected", data: { name: "confirm" }, type: "CallExpression", line: 1, column: 1 }]
         },
         {
             code: "window.confirm(foo)",
-            errors: [{ message: "Unexpected confirm.", type: "CallExpression", line: 1, column: 1 }]
+            errors: [{ messageId: "unexpected", data: { name: "confirm" }, type: "CallExpression", line: 1, column: 1 }]
         },
         {
             code: "window['confirm'](foo)",
-            errors: [{ message: "Unexpected confirm.", type: "CallExpression", line: 1, column: 1 }]
+            errors: [{ messageId: "unexpected", data: { name: "confirm" }, type: "CallExpression", line: 1, column: 1 }]
         },
         {
             code: "prompt(foo)",
-            errors: [{ message: "Unexpected prompt.", type: "CallExpression", line: 1, column: 1 }]
+            errors: [{ messageId: "unexpected", data: { name: "prompt" }, type: "CallExpression", line: 1, column: 1 }]
         },
         {
             code: "window.prompt(foo)",
-            errors: [{ message: "Unexpected prompt.", type: "CallExpression", line: 1, column: 1 }]
+            errors: [{ messageId: "unexpected", data: { name: "prompt" }, type: "CallExpression", line: 1, column: 1 }]
         },
         {
             code: "window['prompt'](foo)",
-            errors: [{ message: "Unexpected prompt.", type: "CallExpression", line: 1, column: 1 }]
+            errors: [{ messageId: "unexpected", data: { name: "prompt" }, type: "CallExpression", line: 1, column: 1 }]
         },
         {
             code: "function alert() {} window.alert(foo)",
-            errors: [{ message: "Unexpected alert.", type: "CallExpression", line: 1, column: 21 }]
+            errors: [{ messageId: "unexpected", data: { name: "alert" }, type: "CallExpression", line: 1, column: 21 }]
         },
         {
             code: "var alert = function() {};\nwindow.alert(foo)",
-            errors: [{ message: "Unexpected alert.", type: "CallExpression", line: 2, column: 1 }]
+            errors: [{ messageId: "unexpected", data: { name: "alert" }, type: "CallExpression", line: 2, column: 1 }]
         },
         {
             code: "function foo(alert) { window.alert(); }",
-            errors: [{ message: "Unexpected alert.", type: "CallExpression", line: 1, column: 23 }]
+            errors: [{ messageId: "unexpected", data: { name: "alert" }, type: "CallExpression", line: 1, column: 23 }]
         },
         {
             code: "function foo() { alert(); }",
-            errors: [{ message: "Unexpected alert.", type: "CallExpression", line: 1, column: 18 }]
+            errors: [{ messageId: "unexpected", data: { name: "alert" }, type: "CallExpression", line: 1, column: 18 }]
         },
         {
             code: "function foo() { var alert = function() {}; }\nalert();",
-            errors: [{ message: "Unexpected alert.", type: "CallExpression", line: 2, column: 1 }]
+            errors: [{ messageId: "unexpected", data: { name: "alert" }, type: "CallExpression", line: 2, column: 1 }]
         },
         {
             code: "this.alert(foo)",
-            errors: [{ message: "Unexpected alert.", type: "CallExpression", line: 1, column: 1 }]
+            errors: [{ messageId: "unexpected", data: { name: "alert" }, type: "CallExpression", line: 1, column: 1 }]
         },
         {
             code: "this['alert'](foo)",
-            errors: [{ message: "Unexpected alert.", type: "CallExpression", line: 1, column: 1 }]
+            errors: [{ messageId: "unexpected", data: { name: "alert" }, type: "CallExpression", line: 1, column: 1 }]
         },
         {
             code: "function foo() { var window = bar; window.alert(); }\nwindow.alert();",
-            errors: [{ message: "Unexpected alert.", type: "CallExpression", line: 2, column: 1 }]
+            errors: [{ messageId: "unexpected", data: { name: "alert" }, type: "CallExpression", line: 2, column: 1 }]
         }
     ]
 });
diff --git a/tests/lib/rules/no-array-constructor.js b/tests/lib/rules/no-array-constructor.js
index 9dddedfa22c..b42c4a7fd39 100644
--- a/tests/lib/rules/no-array-constructor.js
+++ b/tests/lib/rules/no-array-constructor.js
@@ -30,9 +30,9 @@ ruleTester.run("no-array-constructor", rule, {
         "Array.foo()"
     ],
     invalid: [
-        { code: "new Array()", errors: [{ message: "The array literal notation [] is preferrable.", type: "NewExpression" }] },
-        { code: "new Array", errors: [{ message: "The array literal notation [] is preferrable.", type: "NewExpression" }] },
-        { code: "new Array(x, y)", errors: [{ message: "The array literal notation [] is preferrable.", type: "NewExpression" }] },
-        { code: "new Array(0, 1, 2)", errors: [{ message: "The array literal notation [] is preferrable.", type: "NewExpression" }] }
+        { code: "new Array()", errors: [{ messageId: "preferLiteral", type: "NewExpression" }] },
+        { code: "new Array", errors: [{ messageId: "preferLiteral", type: "NewExpression" }] },
+        { code: "new Array(x, y)", errors: [{ messageId: "preferLiteral", type: "NewExpression" }] },
+        { code: "new Array(0, 1, 2)", errors: [{ messageId: "preferLiteral", type: "NewExpression" }] }
     ]
 });
diff --git a/tests/lib/rules/no-await-in-loop.js b/tests/lib/rules/no-await-in-loop.js
index 15673ded2c8..bb74db1c039 100644
--- a/tests/lib/rules/no-await-in-loop.js
+++ b/tests/lib/rules/no-await-in-loop.js
@@ -8,7 +8,7 @@
 const rule = require("../../../lib/rules/no-await-in-loop"),
     RuleTester = require("../../../lib/testers/rule-tester");
 
-const message = "Unexpected `await` inside a loop.";
+const error = { messageId: "unexpectedAwait" };
 
 const ruleTester = new RuleTester({ parserOptions: { ecmaVersion: "2017" } });
 
@@ -41,29 +41,29 @@ ruleTester.run("no-await-in-loop", rule, {
     invalid: [
 
         // While loops
-        { code: "async function foo() { while (baz) { await bar; } }", errors: [message] },
-        { code: "async function foo() { while (await foo()) {  } }", errors: [message] },
+        { code: "async function foo() { while (baz) { await bar; } }", errors: [error] },
+        { code: "async function foo() { while (await foo()) {  } }", errors: [error] },
 
         // For of loops
-        { code: "async function foo() { for (var bar of baz) { await bar; } }", errors: [message] },
-        { code: "async function foo() { for (var bar of baz) await bar; }", errors: [message] },
+        { code: "async function foo() { for (var bar of baz) { await bar; } }", errors: [error] },
+        { code: "async function foo() { for (var bar of baz) await bar; }", errors: [error] },
 
         // For in loops
-        { code: "async function foo() { for (var bar in baz) { await bar; } }", errors: [message] },
+        { code: "async function foo() { for (var bar in baz) { await bar; } }", errors: [error] },
 
         // For loops
-        { code: "async function foo() { for (var i; i < n; i++) { await bar; } }", errors: [message] },
-        { code: "async function foo() { for (var i; await foo(i); i++) {  } }", errors: [message] },
-        { code: "async function foo() { for (var i; i < n; i = await bar) {  } }", errors: [message] },
+        { code: "async function foo() { for (var i; i < n; i++) { await bar; } }", errors: [error] },
+        { code: "async function foo() { for (var i; await foo(i); i++) {  } }", errors: [error] },
+        { code: "async function foo() { for (var i; i < n; i = await bar) {  } }", errors: [error] },
 
         // Do while loops
-        { code: "async function foo() { do { await bar; } while (baz); }", errors: [message] },
-        { code: "async function foo() { do { } while (await bar); }", errors: [message] },
+        { code: "async function foo() { do { await bar; } while (baz); }", errors: [error] },
+        { code: "async function foo() { do { } while (await bar); }", errors: [error] },
 
         // Deep in a loop body
-        { code: "async function foo() { while (true) { if (bar) { foo(await bar); } } }", errors: [message] },
+        { code: "async function foo() { while (true) { if (bar) { foo(await bar); } } }", errors: [error] },
 
         // Deep in a loop condition
-        { code: "async function foo() { while (xyz || 5 > await x) {  } }", errors: [message] }
+        { code: "async function foo() { while (xyz || 5 > await x) {  } }", errors: [error] }
     ]
 });
diff --git a/tests/lib/rules/no-bitwise.js b/tests/lib/rules/no-bitwise.js
index f5edfc6c527..f1ab5ba2373 100644
--- a/tests/lib/rules/no-bitwise.js
+++ b/tests/lib/rules/no-bitwise.js
@@ -29,18 +29,18 @@ ruleTester.run("no-bitwise", rule, {
         { code: "a|0", options: [{ allow: ["|"], int32Hint: false }] }
     ],
     invalid: [
-        { code: "a ^ b", errors: [{ message: "Unexpected use of '^'.", type: "BinaryExpression" }] },
-        { code: "a | b", errors: [{ message: "Unexpected use of '|'.", type: "BinaryExpression" }] },
-        { code: "a & b", errors: [{ message: "Unexpected use of '&'.", type: "BinaryExpression" }] },
-        { code: "a << b", errors: [{ message: "Unexpected use of '<<'.", type: "BinaryExpression" }] },
-        { code: "a >> b", errors: [{ message: "Unexpected use of '>>'.", type: "BinaryExpression" }] },
-        { code: "a >>> b", errors: [{ message: "Unexpected use of '>>>'.", type: "BinaryExpression" }] },
-        { code: "~a", errors: [{ message: "Unexpected use of '~'.", type: "UnaryExpression" }] },
-        { code: "a ^= b", errors: [{ message: "Unexpected use of '^='.", type: "AssignmentExpression" }] },
-        { code: "a |= b", errors: [{ message: "Unexpected use of '|='.", type: "AssignmentExpression" }] },
-        { code: "a &= b", errors: [{ message: "Unexpected use of '&='.", type: "AssignmentExpression" }] },
-        { code: "a <<= b", errors: [{ message: "Unexpected use of '<<='.", type: "AssignmentExpression" }] },
-        { code: "a >>= b", errors: [{ message: "Unexpected use of '>>='.", type: "AssignmentExpression" }] },
-        { code: "a >>>= b", errors: [{ message: "Unexpected use of '>>>='.", type: "AssignmentExpression" }] }
+        { code: "a ^ b", errors: [{ messageId: "unexpected", data: { operator: "^" }, type: "BinaryExpression" }] },
+        { code: "a | b", errors: [{ messageId: "unexpected", data: { operator: "|" }, type: "BinaryExpression" }] },
+        { code: "a & b", errors: [{ messageId: "unexpected", data: { operator: "&" }, type: "BinaryExpression" }] },
+        { code: "a << b", errors: [{ messageId: "unexpected", data: { operator: "<<" }, type: "BinaryExpression" }] },
+        { code: "a >> b", errors: [{ messageId: "unexpected", data: { operator: ">>" }, type: "BinaryExpression" }] },
+        { code: "a >>> b", errors: [{ messageId: "unexpected", data: { operator: ">>>" }, type: "BinaryExpression" }] },
+        { code: "~a", errors: [{ messageId: "unexpected", data: { operator: "~" }, type: "UnaryExpression" }] },
+        { code: "a ^= b", errors: [{ messageId: "unexpected", data: { operator: "^=" }, type: "AssignmentExpression" }] },
+        { code: "a |= b", errors: [{ messageId: "unexpected", data: { operator: "|=" }, type: "AssignmentExpression" }] },
+        { code: "a &= b", errors: [{ messageId: "unexpected", data: { operator: "&=" }, type: "AssignmentExpression" }] },
+        { code: "a <<= b", errors: [{ messageId: "unexpected", data: { operator: "<<=" }, type: "AssignmentExpression" }] },
+        { code: "a >>= b", errors: [{ messageId: "unexpected", data: { operator: ">>=" }, type: "AssignmentExpression" }] },
+        { code: "a >>>= b", errors: [{ messageId: "unexpected", data: { operator: ">>>=" }, type: "AssignmentExpression" }] }
     ]
 });
diff --git a/tests/lib/rules/no-buffer-constructor.js b/tests/lib/rules/no-buffer-constructor.js
index c3540e5e4ef..9bdaccb17d1 100644
--- a/tests/lib/rules/no-buffer-constructor.js
+++ b/tests/lib/rules/no-buffer-constructor.js
@@ -17,11 +17,17 @@ const RuleTester = require("../../../lib/testers/rule-tester");
 //------------------------------------------------------------------------------
 
 const CALL_ERROR = {
-    message: "Buffer() is deprecated. Use Buffer.from(), Buffer.alloc(), or Buffer.allocUnsafe() instead.",
+    messageId: "deprecated",
+    data: {
+        expr: "Buffer()"
+    },
     type: "CallExpression"
 };
 const CONSTRUCT_ERROR = {
-    message: "new Buffer() is deprecated. Use Buffer.from(), Buffer.alloc(), or Buffer.allocUnsafe() instead.",
+    messageId: "deprecated",
+    data: {
+        expr: "new Buffer()"
+    },
     type: "NewExpression"
 };
 
diff --git a/tests/lib/rules/no-caller.js b/tests/lib/rules/no-caller.js
index da56c5180e1..a55a823e01d 100644
--- a/tests/lib/rules/no-caller.js
+++ b/tests/lib/rules/no-caller.js
@@ -26,7 +26,7 @@ ruleTester.run("no-caller", rule, {
         "var x = arguments[caller]"
     ],
     invalid: [
-        { code: "var x = arguments.callee", errors: [{ message: "Avoid arguments.callee.", type: "MemberExpression" }] },
-        { code: "var x = arguments.caller", errors: [{ message: "Avoid arguments.caller.", type: "MemberExpression" }] }
+        { code: "var x = arguments.callee", errors: [{ messageId: "unexpected", data: { prop: "callee" }, type: "MemberExpression" }] },
+        { code: "var x = arguments.caller", errors: [{ messageId: "unexpected", data: { prop: "caller" }, type: "MemberExpression" }] }
     ]
 });
diff --git a/tests/lib/rules/no-case-declarations.js b/tests/lib/rules/no-case-declarations.js
index 8d86f311a75..d72ad515d7e 100644
--- a/tests/lib/rules/no-case-declarations.js
+++ b/tests/lib/rules/no-case-declarations.js
@@ -41,42 +41,42 @@ ruleTester.run("no-case-declarations", rule, {
         {
             code: "switch (a) { case 1: let x = 1; break; }",
             parserOptions: { ecmaVersion: 6 },
-            errors: [{ message: "Unexpected lexical declaration in case block." }]
+            errors: [{ messageId: "unexpected" }]
         },
         {
             code: "switch (a) { default: let x = 2; break; }",
             parserOptions: { ecmaVersion: 6 },
-            errors: [{ message: "Unexpected lexical declaration in case block." }]
+            errors: [{ messageId: "unexpected" }]
         },
         {
             code: "switch (a) { case 1: const x = 1; break; }",
             parserOptions: { ecmaVersion: 6 },
-            errors: [{ message: "Unexpected lexical declaration in case block." }]
+            errors: [{ messageId: "unexpected" }]
         },
         {
             code: "switch (a) { default: const x = 2; break; }",
             parserOptions: { ecmaVersion: 6 },
-            errors: [{ message: "Unexpected lexical declaration in case block." }]
+            errors: [{ messageId: "unexpected" }]
         },
         {
             code: "switch (a) { case 1: function f() {} break; }",
             parserOptions: { ecmaVersion: 6 },
-            errors: [{ message: "Unexpected lexical declaration in case block." }]
+            errors: [{ messageId: "unexpected" }]
         },
         {
             code: "switch (a) { default: function f() {} break; }",
             parserOptions: { ecmaVersion: 6 },
-            errors: [{ message: "Unexpected lexical declaration in case block." }]
+            errors: [{ messageId: "unexpected" }]
         },
         {
             code: "switch (a) { case 1: class C {} break; }",
             parserOptions: { ecmaVersion: 6 },
-            errors: [{ message: "Unexpected lexical declaration in case block." }]
+            errors: [{ messageId: "unexpected" }]
         },
         {
             code: "switch (a) { default: class C {} break; }",
             parserOptions: { ecmaVersion: 6 },
-            errors: [{ message: "Unexpected lexical declaration in case block." }]
+            errors: [{ messageId: "unexpected" }]
         }
     ]
 });
diff --git a/tests/lib/rules/no-catch-shadow.js b/tests/lib/rules/no-catch-shadow.js
index 3d1024f9ea8..cd6c3f32b63 100644
--- a/tests/lib/rules/no-catch-shadow.js
+++ b/tests/lib/rules/no-catch-shadow.js
@@ -43,9 +43,9 @@ ruleTester.run("no-catch-shadow", rule, {
         }
     ],
     invalid: [
-        { code: "var foo = 1; try { bar(); } catch(foo) { }", errors: [{ message: "Value of 'foo' may be overwritten in IE 8 and earlier.", type: "CatchClause" }] },
-        { code: "function foo(){} try { bar(); } catch(foo) { }", errors: [{ message: "Value of 'foo' may be overwritten in IE 8 and earlier.", type: "CatchClause" }] },
-        { code: "function foo(){ try { bar(); } catch(foo) { } }", errors: [{ message: "Value of 'foo' may be overwritten in IE 8 and earlier.", type: "CatchClause" }] },
-        { code: "var foo = function(){ try { bar(); } catch(foo) { } };", errors: [{ message: "Value of 'foo' may be overwritten in IE 8 and earlier.", type: "CatchClause" }] }
+        { code: "var foo = 1; try { bar(); } catch(foo) { }", errors: [{ messageId: "mutable", data: { name: "foo" }, type: "CatchClause" }] },
+        { code: "function foo(){} try { bar(); } catch(foo) { }", errors: [{ messageId: "mutable", data: { name: "foo" }, type: "CatchClause" }] },
+        { code: "function foo(){ try { bar(); } catch(foo) { } }", errors: [{ messageId: "mutable", data: { name: "foo" }, type: "CatchClause" }] },
+        { code: "var foo = function(){ try { bar(); } catch(foo) { } };", errors: [{ messageId: "mutable", data: { name: "foo" }, type: "CatchClause" }] }
     ]
 });
diff --git a/tests/lib/rules/no-class-assign.js b/tests/lib/rules/no-class-assign.js
index 119fd9812ef..3781b1f20d6 100644
--- a/tests/lib/rules/no-class-assign.js
+++ b/tests/lib/rules/no-class-assign.js
@@ -37,33 +37,33 @@ ruleTester.run("no-class-assign", rule, {
     invalid: [
         {
             code: "class A { } A = 0;",
-            errors: [{ message: "'A' is a class.", type: "Identifier" }]
+            errors: [{ messageId: "class", data: { name: "A" }, type: "Identifier" }]
         },
         {
             code: "class A { } ({A} = 0);",
-            errors: [{ message: "'A' is a class.", type: "Identifier" }]
+            errors: [{ messageId: "class", data: { name: "A" }, type: "Identifier" }]
         },
         {
             code: "class A { } ({b: A = 0} = {});",
-            errors: [{ message: "'A' is a class.", type: "Identifier" }]
+            errors: [{ messageId: "class", data: { name: "A" }, type: "Identifier" }]
         },
         {
             code: "A = 0; class A { }",
-            errors: [{ message: "'A' is a class.", type: "Identifier" }]
+            errors: [{ messageId: "class", data: { name: "A" }, type: "Identifier" }]
         },
         {
             code: "class A { b() { A = 0; } }",
-            errors: [{ message: "'A' is a class.", type: "Identifier" }]
+            errors: [{ messageId: "class", data: { name: "A" }, type: "Identifier" }]
         },
         {
             code: "let A = class A { b() { A = 0; } }",
-            errors: [{ message: "'A' is a class.", type: "Identifier" }]
+            errors: [{ messageId: "class", data: { name: "A" }, type: "Identifier" }]
         },
         {
             code: "class A { } A = 0; A = 1;",
             errors: [
-                { message: "'A' is a class.", type: "Identifier", line: 1, column: 13 },
-                { message: "'A' is a class.", type: "Identifier", line: 1, column: 20 }
+                { messageId: "class", data: { name: "A" }, type: "Identifier", line: 1, column: 13 },
+                { messageId: "class", data: { name: "A" }, type: "Identifier", line: 1, column: 20 }
             ]
         }
     ]
diff --git a/tests/lib/rules/no-compare-neg-zero.js b/tests/lib/rules/no-compare-neg-zero.js
index d8f4812f35a..19429026080 100644
--- a/tests/lib/rules/no-compare-neg-zero.js
+++ b/tests/lib/rules/no-compare-neg-zero.js
@@ -55,84 +55,96 @@ ruleTester.run("no-compare-neg-zero", rule, {
         {
             code: "x === -0",
             errors: [{
-                message: "Do not use the '===' operator to compare against -0.",
+                messageId: "unexpected",
+                data: { operator: "===" },
                 type: "BinaryExpression"
             }]
         },
         {
             code: "-0 === x",
             errors: [{
-                message: "Do not use the '===' operator to compare against -0.",
+                messageId: "unexpected",
+                data: { operator: "===" },
                 type: "BinaryExpression"
             }]
         },
         {
             code: "x == -0",
             errors: [{
-                message: "Do not use the '==' operator to compare against -0.",
+                messageId: "unexpected",
+                data: { operator: "==" },
                 type: "BinaryExpression"
             }]
         },
         {
             code: "-0 == x",
             errors: [{
-                message: "Do not use the '==' operator to compare against -0.",
+                messageId: "unexpected",
+                data: { operator: "==" },
                 type: "BinaryExpression"
             }]
         },
         {
             code: "x > -0",
             errors: [{
-                message: "Do not use the '>' operator to compare against -0.",
+                messageId: "unexpected",
+                data: { operator: ">" },
                 type: "BinaryExpression"
             }]
         },
         {
             code: "-0 > x",
             errors: [{
-                message: "Do not use the '>' operator to compare against -0.",
+                messageId: "unexpected",
+                data: { operator: ">" },
                 type: "BinaryExpression"
             }]
         },
         {
             code: "x >= -0",
             errors: [{
-                message: "Do not use the '>=' operator to compare against -0.",
+                messageId: "unexpected",
+                data: { operator: ">=" },
                 type: "BinaryExpression"
             }]
         },
         {
             code: "-0 >= x",
             errors: [{
-                message: "Do not use the '>=' operator to compare against -0.",
+                messageId: "unexpected",
+                data: { operator: ">=" },
                 type: "BinaryExpression"
             }]
         },
         {
             code: "x < -0",
             errors: [{
-                message: "Do not use the '<' operator to compare against -0.",
+                messageId: "unexpected",
+                data: { operator: "<" },
                 type: "BinaryExpression"
             }]
         },
         {
             code: "-0 < x",
             errors: [{
-                message: "Do not use the '<' operator to compare against -0.",
+                messageId: "unexpected",
+                data: { operator: "<" },
                 type: "BinaryExpression"
             }]
         },
         {
             code: "x <= -0",
             errors: [{
-                message: "Do not use the '<=' operator to compare against -0.",
+                messageId: "unexpected",
+                data: { operator: "<=" },
                 type: "BinaryExpression"
             }]
         },
         {
             code: "-0 <= x",
             errors: [{
-                message: "Do not use the '<=' operator to compare against -0.",
+                messageId: "unexpected",
+                data: { operator: "<=" },
                 type: "BinaryExpression"
             }]
         }
diff --git a/tests/lib/rules/no-cond-assign.js b/tests/lib/rules/no-cond-assign.js
index 36cd15a1e10..b192635c887 100644
--- a/tests/lib/rules/no-cond-assign.js
+++ b/tests/lib/rules/no-cond-assign.js
@@ -11,7 +11,6 @@
 
 const rule = require("../../../lib/rules/no-cond-assign"),
     RuleTester = require("../../../lib/testers/rule-tester");
-const ERROR_MESSAGE = "Expected a conditional expression and instead saw an assignment.";
 
 //------------------------------------------------------------------------------
 // Tests
@@ -44,22 +43,22 @@ ruleTester.run("no-cond-assign", rule, {
         { code: "x = 0;", options: ["always"] }
     ],
     invalid: [
-        { code: "var x; if (x = 0) { var b = 1; }", errors: [{ message: ERROR_MESSAGE, type: "IfStatement", line: 1, column: 12 }] },
-        { code: "var x; while (x = 0) { var b = 1; }", errors: [{ message: ERROR_MESSAGE, type: "WhileStatement" }] },
-        { code: "var x = 0, y; do { y = x; } while (x = x + 1);", errors: [{ message: ERROR_MESSAGE, type: "DoWhileStatement" }] },
-        { code: "var x; for(; x+=1 ;){};", errors: [{ message: ERROR_MESSAGE, type: "ForStatement" }] },
-        { code: "var x; if ((x) = (0));", errors: [{ message: ERROR_MESSAGE, type: "IfStatement" }] },
-        { code: "if (someNode || (someNode = parentNode)) { }", options: ["always"], errors: [{ message: "Unexpected assignment within an 'if' statement.", type: "IfStatement" }] },
-        { code: "while (someNode || (someNode = parentNode)) { }", options: ["always"], errors: [{ message: "Unexpected assignment within a 'while' statement.", type: "WhileStatement" }] },
-        { code: "do { } while (someNode || (someNode = parentNode));", options: ["always"], errors: [{ message: "Unexpected assignment within a 'do...while' statement.", type: "DoWhileStatement" }] },
-        { code: "for (; (typeof l === 'undefined' ? (l = 0) : l); i++) { }", options: ["always"], errors: [{ message: "Unexpected assignment within a 'for' statement.", type: "ForStatement" }] },
-        { code: "if (x = 0) { }", options: ["always"], errors: [{ message: "Unexpected assignment within an 'if' statement.", type: "IfStatement" }] },
-        { code: "while (x = 0) { }", options: ["always"], errors: [{ message: "Unexpected assignment within a 'while' statement.", type: "WhileStatement" }] },
-        { code: "do { } while (x = x + 1);", options: ["always"], errors: [{ message: "Unexpected assignment within a 'do...while' statement.", type: "DoWhileStatement" }] },
-        { code: "for(; x = y; ) { }", options: ["always"], errors: [{ message: "Unexpected assignment within a 'for' statement.", type: "ForStatement" }] },
-        { code: "if ((x = 0)) { }", options: ["always"], errors: [{ message: "Unexpected assignment within an 'if' statement.", type: "IfStatement" }] },
-        { code: "while ((x = 0)) { }", options: ["always"], errors: [{ message: "Unexpected assignment within a 'while' statement.", type: "WhileStatement" }] },
-        { code: "do { } while ((x = x + 1));", options: ["always"], errors: [{ message: "Unexpected assignment within a 'do...while' statement.", type: "DoWhileStatement" }] },
-        { code: "for(; (x = y); ) { }", options: ["always"], errors: [{ message: "Unexpected assignment within a 'for' statement.", type: "ForStatement" }] }
+        { code: "var x; if (x = 0) { var b = 1; }", errors: [{ messageId: "missing", type: "IfStatement", line: 1, column: 12 }] },
+        { code: "var x; while (x = 0) { var b = 1; }", errors: [{ messageId: "missing", type: "WhileStatement" }] },
+        { code: "var x = 0, y; do { y = x; } while (x = x + 1);", errors: [{ messageId: "missing", type: "DoWhileStatement" }] },
+        { code: "var x; for(; x+=1 ;){};", errors: [{ messageId: "missing", type: "ForStatement" }] },
+        { code: "var x; if ((x) = (0));", errors: [{ messageId: "missing", type: "IfStatement" }] },
+        { code: "if (someNode || (someNode = parentNode)) { }", options: ["always"], errors: [{ messageId: "unexpected", data: { type: "an 'if' statement" }, type: "IfStatement" }] },
+        { code: "while (someNode || (someNode = parentNode)) { }", options: ["always"], errors: [{ messageId: "unexpected", data: { type: "a 'while' statement" }, type: "WhileStatement" }] },
+        { code: "do { } while (someNode || (someNode = parentNode));", options: ["always"], errors: [{ messageId: "unexpected", data: { type: "a 'do...while' statement" }, type: "DoWhileStatement" }] },
+        { code: "for (; (typeof l === 'undefined' ? (l = 0) : l); i++) { }", options: ["always"], errors: [{ messageId: "unexpected", data: { type: "a 'for' statement" }, type: "ForStatement" }] },
+        { code: "if (x = 0) { }", options: ["always"], errors: [{ messageId: "unexpected", data: { type: "an 'if' statement" }, type: "IfStatement" }] },
+        { code: "while (x = 0) { }", options: ["always"], errors: [{ messageId: "unexpected", data: { type: "a 'while' statement" }, type: "WhileStatement" }] },
+        { code: "do { } while (x = x + 1);", options: ["always"], errors: [{ messageId: "unexpected", data: { type: "a 'do...while' statement" }, type: "DoWhileStatement" }] },
+        { code: "for(; x = y; ) { }", options: ["always"], errors: [{ messageId: "unexpected", data: { type: "a 'for' statement" }, type: "ForStatement" }] },
+        { code: "if ((x = 0)) { }", options: ["always"], errors: [{ messageId: "unexpected", data: { type: "an 'if' statement" }, type: "IfStatement" }] },
+        { code: "while ((x = 0)) { }", options: ["always"], errors: [{ messageId: "unexpected", data: { type: "a 'while' statement" }, type: "WhileStatement" }] },
+        { code: "do { } while ((x = x + 1));", options: ["always"], errors: [{ messageId: "unexpected", data: { type: "a 'do...while' statement" }, type: "DoWhileStatement" }] },
+        { code: "for(; (x = y); ) { }", options: ["always"], errors: [{ messageId: "unexpected", data: { type: "a 'for' statement" }, type: "ForStatement" }] }
     ]
 });
diff --git a/tests/lib/rules/no-confusing-arrow.js b/tests/lib/rules/no-confusing-arrow.js
index e79461beee0..7df2538a2d0 100644
--- a/tests/lib/rules/no-confusing-arrow.js
+++ b/tests/lib/rules/no-confusing-arrow.js
@@ -29,40 +29,40 @@ ruleTester.run("no-confusing-arrow", rule, {
         {
             code: "a => 1 ? 2 : 3",
             output: null,
-            errors: [{ message: "Arrow function used ambiguously with a conditional expression." }]
+            errors: [{ messageId: "confusing" }]
         },
         {
             code: "var x = a => 1 ? 2 : 3",
             output: null,
-            errors: [{ message: "Arrow function used ambiguously with a conditional expression." }]
+            errors: [{ messageId: "confusing" }]
         },
         {
             code: "var x = (a) => 1 ? 2 : 3",
             output: null,
-            errors: [{ message: "Arrow function used ambiguously with a conditional expression." }]
+            errors: [{ messageId: "confusing" }]
         },
         {
             code: "var x = a => (1 ? 2 : 3)",
             output: null,
-            errors: [{ message: "Arrow function used ambiguously with a conditional expression." }]
+            errors: [{ messageId: "confusing" }]
         },
         {
             code: "a => 1 ? 2 : 3",
             output: "a => (1 ? 2 : 3)",
             options: [{ allowParens: true }],
-            errors: [{ message: "Arrow function used ambiguously with a conditional expression." }]
+            errors: [{ messageId: "confusing" }]
         },
         {
             code: "var x = a => 1 ? 2 : 3",
             output: "var x = a => (1 ? 2 : 3)",
             options: [{ allowParens: true }],
-            errors: [{ message: "Arrow function used ambiguously with a conditional expression." }]
+            errors: [{ messageId: "confusing" }]
         },
         {
             code: "var x = (a) => 1 ? 2 : 3",
             output: "var x = (a) => (1 ? 2 : 3)",
             options: [{ allowParens: true }],
-            errors: [{ message: "Arrow function used ambiguously with a conditional expression." }]
+            errors: [{ messageId: "confusing" }]
         }
     ]
 });
diff --git a/tests/lib/rules/no-console.js b/tests/lib/rules/no-console.js
index ceb04ac2d9a..76a39227e5c 100644
--- a/tests/lib/rules/no-console.js
+++ b/tests/lib/rules/no-console.js
@@ -40,24 +40,24 @@ ruleTester.run("no-console", rule, {
     invalid: [
 
         // no options
-        { code: "console.log(foo)", errors: [{ message: "Unexpected console statement.", type: "MemberExpression" }] },
-        { code: "console.error(foo)", errors: [{ message: "Unexpected console statement.", type: "MemberExpression" }] },
-        { code: "console.info(foo)", errors: [{ message: "Unexpected console statement.", type: "MemberExpression" }] },
-        { code: "console.warn(foo)", errors: [{ message: "Unexpected console statement.", type: "MemberExpression" }] },
+        { code: "console.log(foo)", errors: [{ messageId: "unexpected", type: "MemberExpression" }] },
+        { code: "console.error(foo)", errors: [{ messageId: "unexpected", type: "MemberExpression" }] },
+        { code: "console.info(foo)", errors: [{ messageId: "unexpected", type: "MemberExpression" }] },
+        { code: "console.warn(foo)", errors: [{ messageId: "unexpected", type: "MemberExpression" }] },
 
         //  one option
-        { code: "console.log(foo)", options: [{ allow: ["error"] }], errors: [{ message: "Unexpected console statement.", type: "MemberExpression" }] },
-        { code: "console.error(foo)", options: [{ allow: ["warn"] }], errors: [{ message: "Unexpected console statement.", type: "MemberExpression" }] },
-        { code: "console.info(foo)", options: [{ allow: ["log"] }], errors: [{ message: "Unexpected console statement.", type: "MemberExpression" }] },
-        { code: "console.warn(foo)", options: [{ allow: ["error"] }], errors: [{ message: "Unexpected console statement.", type: "MemberExpression" }] },
+        { code: "console.log(foo)", options: [{ allow: ["error"] }], errors: [{ messageId: "unexpected", type: "MemberExpression" }] },
+        { code: "console.error(foo)", options: [{ allow: ["warn"] }], errors: [{ messageId: "unexpected", type: "MemberExpression" }] },
+        { code: "console.info(foo)", options: [{ allow: ["log"] }], errors: [{ messageId: "unexpected", type: "MemberExpression" }] },
+        { code: "console.warn(foo)", options: [{ allow: ["error"] }], errors: [{ messageId: "unexpected", type: "MemberExpression" }] },
 
         // multiple options
-        { code: "console.log(foo)", options: [{ allow: ["warn", "info"] }], errors: [{ message: "Unexpected console statement.", type: "MemberExpression" }] },
-        { code: "console.error(foo)", options: [{ allow: ["warn", "info", "log"] }], errors: [{ message: "Unexpected console statement.", type: "MemberExpression" }] },
-        { code: "console.info(foo)", options: [{ allow: ["warn", "error", "log"] }], errors: [{ message: "Unexpected console statement.", type: "MemberExpression" }] },
-        { code: "console.warn(foo)", options: [{ allow: ["info", "log"] }], errors: [{ message: "Unexpected console statement.", type: "MemberExpression" }] },
+        { code: "console.log(foo)", options: [{ allow: ["warn", "info"] }], errors: [{ messageId: "unexpected", type: "MemberExpression" }] },
+        { code: "console.error(foo)", options: [{ allow: ["warn", "info", "log"] }], errors: [{ messageId: "unexpected", type: "MemberExpression" }] },
+        { code: "console.info(foo)", options: [{ allow: ["warn", "error", "log"] }], errors: [{ messageId: "unexpected", type: "MemberExpression" }] },
+        { code: "console.warn(foo)", options: [{ allow: ["info", "log"] }], errors: [{ messageId: "unexpected", type: "MemberExpression" }] },
 
         // In case that implicit global variable of 'console' exists
-        { code: "console.log(foo)", errors: [{ message: "Unexpected console statement.", type: "MemberExpression" }], env: { node: true } }
+        { code: "console.log(foo)", errors: [{ messageId: "unexpected", type: "MemberExpression" }], env: { node: true } }
     ]
 });
diff --git a/tests/lib/rules/no-const-assign.js b/tests/lib/rules/no-const-assign.js
index 761ea73cc78..c6b03da9e1c 100644
--- a/tests/lib/rules/no-const-assign.js
+++ b/tests/lib/rules/no-const-assign.js
@@ -38,50 +38,50 @@ ruleTester.run("no-const-assign", rule, {
     invalid: [
         {
             code: "const x = 0; x = 1;",
-            errors: [{ message: "'x' is constant.", type: "Identifier" }]
+            errors: [{ messageId: "const", data: { name: "x" }, type: "Identifier" }]
         },
         {
             code: "const {a: x} = {a: 0}; x = 1;",
-            errors: [{ message: "'x' is constant.", type: "Identifier" }]
+            errors: [{ messageId: "const", data: { name: "x" }, type: "Identifier" }]
         },
         {
             code: "const x = 0; ({x} = {x: 1});",
-            errors: [{ message: "'x' is constant.", type: "Identifier" }]
+            errors: [{ messageId: "const", data: { name: "x" }, type: "Identifier" }]
         },
         {
             code: "const x = 0; ({a: x = 1} = {});",
-            errors: [{ message: "'x' is constant.", type: "Identifier" }]
+            errors: [{ messageId: "const", data: { name: "x" }, type: "Identifier" }]
         },
         {
             code: "const x = 0; x += 1;",
-            errors: [{ message: "'x' is constant.", type: "Identifier" }]
+            errors: [{ messageId: "const", data: { name: "x" }, type: "Identifier" }]
         },
         {
             code: "const x = 0; ++x;",
-            errors: [{ message: "'x' is constant.", type: "Identifier" }]
+            errors: [{ messageId: "const", data: { name: "x" }, type: "Identifier" }]
         },
         {
             code: "for (const i = 0; i < 10; ++i) { foo(i); }",
-            errors: [{ message: "'i' is constant.", type: "Identifier" }]
+            errors: [{ messageId: "const", data: { name: "i" }, type: "Identifier" }]
         },
         {
             code: "const x = 0; x = 1; x = 2;",
             errors: [
-                { message: "'x' is constant.", type: "Identifier", line: 1, column: 14 },
-                { message: "'x' is constant.", type: "Identifier", line: 1, column: 21 }
+                { messageId: "const", data: { name: "x" }, type: "Identifier", line: 1, column: 14 },
+                { messageId: "const", data: { name: "x" }, type: "Identifier", line: 1, column: 21 }
             ]
         },
         {
             code: "const x = 0; function foo() { x = x + 1; }",
-            errors: [{ message: "'x' is constant.", type: "Identifier" }]
+            errors: [{ messageId: "const", data: { name: "x" }, type: "Identifier" }]
         },
         {
             code: "const x = 0; function foo(a) { x = a; }",
-            errors: [{ message: "'x' is constant.", type: "Identifier" }]
+            errors: [{ messageId: "const", data: { name: "x" }, type: "Identifier" }]
         },
         {
             code: "const x = 0; while (true) { x = x + 1; }",
-            errors: [{ message: "'x' is constant.", type: "Identifier" }]
+            errors: [{ messageId: "const", data: { name: "x" }, type: "Identifier" }]
         }
     ]
 });
diff --git a/tests/lib/rules/no-constant-condition.js b/tests/lib/rules/no-constant-condition.js
index 9f7bc4c0d24..1ec03f0e7ab 100644
--- a/tests/lib/rules/no-constant-condition.js
+++ b/tests/lib/rules/no-constant-condition.js
@@ -71,90 +71,90 @@ ruleTester.run("no-constant-condition", rule, {
         "function* foo() { for (let x = yield; ; x++) { yield; }}"
     ],
     invalid: [
-        { code: "for(;true;);", errors: [{ message: "Unexpected constant condition.", type: "Literal" }] },
-        { code: "do{}while(true)", errors: [{ message: "Unexpected constant condition.", type: "Literal" }] },
-        { code: "do{}while(t = -2)", errors: [{ message: "Unexpected constant condition.", type: "AssignmentExpression" }] },
-        { code: "true ? 1 : 2;", errors: [{ message: "Unexpected constant condition.", type: "Literal" }] },
-        { code: "q = 0 ? 1 : 2;", errors: [{ message: "Unexpected constant condition.", type: "Literal" }] },
-        { code: "(q = 0) ? 1 : 2;", errors: [{ message: "Unexpected constant condition.", type: "AssignmentExpression" }] },
-        { code: "if(-2);", errors: [{ message: "Unexpected constant condition.", type: "UnaryExpression" }] },
-        { code: "if(true);", errors: [{ message: "Unexpected constant condition.", type: "Literal" }] },
-        { code: "if({});", errors: [{ message: "Unexpected constant condition.", type: "ObjectExpression" }] },
-        { code: "if(0 < 1);", errors: [{ message: "Unexpected constant condition.", type: "BinaryExpression" }] },
-        { code: "if(0 || 1);", errors: [{ message: "Unexpected constant condition.", type: "LogicalExpression" }] },
-        { code: "if(a, 1);", errors: [{ message: "Unexpected constant condition.", type: "SequenceExpression" }] },
-
-        { code: "while([]);", errors: [{ message: "Unexpected constant condition.", type: "ArrayExpression" }] },
-        { code: "while(~!0);", errors: [{ message: "Unexpected constant condition.", type: "UnaryExpression" }] },
-        { code: "while(x = 1);", errors: [{ message: "Unexpected constant condition.", type: "AssignmentExpression" }] },
-        { code: "while(function(){});", errors: [{ message: "Unexpected constant condition.", type: "FunctionExpression" }] },
-        { code: "while(true);", errors: [{ message: "Unexpected constant condition.", type: "Literal" }] },
-        { code: "while(() => {});", errors: [{ message: "Unexpected constant condition.", type: "ArrowFunctionExpression" }] },
+        { code: "for(;true;);", errors: [{ messageId: "unexpected", type: "Literal" }] },
+        { code: "do{}while(true)", errors: [{ messageId: "unexpected", type: "Literal" }] },
+        { code: "do{}while(t = -2)", errors: [{ messageId: "unexpected", type: "AssignmentExpression" }] },
+        { code: "true ? 1 : 2;", errors: [{ messageId: "unexpected", type: "Literal" }] },
+        { code: "q = 0 ? 1 : 2;", errors: [{ messageId: "unexpected", type: "Literal" }] },
+        { code: "(q = 0) ? 1 : 2;", errors: [{ messageId: "unexpected", type: "AssignmentExpression" }] },
+        { code: "if(-2);", errors: [{ messageId: "unexpected", type: "UnaryExpression" }] },
+        { code: "if(true);", errors: [{ messageId: "unexpected", type: "Literal" }] },
+        { code: "if({});", errors: [{ messageId: "unexpected", type: "ObjectExpression" }] },
+        { code: "if(0 < 1);", errors: [{ messageId: "unexpected", type: "BinaryExpression" }] },
+        { code: "if(0 || 1);", errors: [{ messageId: "unexpected", type: "LogicalExpression" }] },
+        { code: "if(a, 1);", errors: [{ messageId: "unexpected", type: "SequenceExpression" }] },
+
+        { code: "while([]);", errors: [{ messageId: "unexpected", type: "ArrayExpression" }] },
+        { code: "while(~!0);", errors: [{ messageId: "unexpected", type: "UnaryExpression" }] },
+        { code: "while(x = 1);", errors: [{ messageId: "unexpected", type: "AssignmentExpression" }] },
+        { code: "while(function(){});", errors: [{ messageId: "unexpected", type: "FunctionExpression" }] },
+        { code: "while(true);", errors: [{ messageId: "unexpected", type: "Literal" }] },
+        { code: "while(() => {});", errors: [{ messageId: "unexpected", type: "ArrowFunctionExpression" }] },
 
         // #5228 , typeof conditions
-        { code: "if(typeof x){}", errors: [{ message: "Unexpected constant condition.", type: "UnaryExpression" }] },
-        { code: "if(typeof 'abc' === 'string'){}", errors: [{ message: "Unexpected constant condition.", type: "BinaryExpression" }] },
-        { code: "if(a = typeof b){}", errors: [{ message: "Unexpected constant condition.", type: "AssignmentExpression" }] },
-        { code: "if(a, typeof b){}", errors: [{ message: "Unexpected constant condition.", type: "SequenceExpression" }] },
-        { code: "if(typeof 'a' == 'string' || typeof 'b' == 'string'){}", errors: [{ message: "Unexpected constant condition.", type: "LogicalExpression" }] },
-        { code: "while(typeof x){}", errors: [{ message: "Unexpected constant condition.", type: "UnaryExpression" }] },
+        { code: "if(typeof x){}", errors: [{ messageId: "unexpected", type: "UnaryExpression" }] },
+        { code: "if(typeof 'abc' === 'string'){}", errors: [{ messageId: "unexpected", type: "BinaryExpression" }] },
+        { code: "if(a = typeof b){}", errors: [{ messageId: "unexpected", type: "AssignmentExpression" }] },
+        { code: "if(a, typeof b){}", errors: [{ messageId: "unexpected", type: "SequenceExpression" }] },
+        { code: "if(typeof 'a' == 'string' || typeof 'b' == 'string'){}", errors: [{ messageId: "unexpected", type: "LogicalExpression" }] },
+        { code: "while(typeof x){}", errors: [{ messageId: "unexpected", type: "UnaryExpression" }] },
 
         // #5726, void conditions
-        { code: "if(1 || void x);", errors: [{ message: "Unexpected constant condition.", type: "LogicalExpression" }] },
-        { code: "if(void x);", errors: [{ message: "Unexpected constant condition.", type: "UnaryExpression" }] },
-        { code: "if(y = void x);", errors: [{ message: "Unexpected constant condition.", type: "AssignmentExpression" }] },
-        { code: "if(x, void x);", errors: [{ message: "Unexpected constant condition.", type: "SequenceExpression" }] },
-        { code: "if(void x === void y);", errors: [{ message: "Unexpected constant condition.", type: "BinaryExpression" }] },
-        { code: "if(void x && a);", errors: [{ message: "Unexpected constant condition.", type: "LogicalExpression" }] },
-        { code: "if(a && void x);", errors: [{ message: "Unexpected constant condition.", type: "LogicalExpression" }] },
+        { code: "if(1 || void x);", errors: [{ messageId: "unexpected", type: "LogicalExpression" }] },
+        { code: "if(void x);", errors: [{ messageId: "unexpected", type: "UnaryExpression" }] },
+        { code: "if(y = void x);", errors: [{ messageId: "unexpected", type: "AssignmentExpression" }] },
+        { code: "if(x, void x);", errors: [{ messageId: "unexpected", type: "SequenceExpression" }] },
+        { code: "if(void x === void y);", errors: [{ messageId: "unexpected", type: "BinaryExpression" }] },
+        { code: "if(void x && a);", errors: [{ messageId: "unexpected", type: "LogicalExpression" }] },
+        { code: "if(a && void x);", errors: [{ messageId: "unexpected", type: "LogicalExpression" }] },
 
         // #5693
-        { code: "if(false && abc==='str'){}", errors: [{ message: "Unexpected constant condition.", type: "LogicalExpression" }] },
-        { code: "if(true || abc==='str'){}", errors: [{ message: "Unexpected constant condition.", type: "LogicalExpression" }] },
-        { code: "if(abc==='str' || true){}", errors: [{ message: "Unexpected constant condition.", type: "LogicalExpression" }] },
-        { code: "if(abc==='str' || true || def ==='str'){}", errors: [{ message: "Unexpected constant condition.", type: "LogicalExpression" }] },
-        { code: "if(false || true){}", errors: [{ message: "Unexpected constant condition.", type: "LogicalExpression" }] },
-        { code: "if(typeof abc==='str' || true){}", errors: [{ message: "Unexpected constant condition.", type: "LogicalExpression" }] },
+        { code: "if(false && abc==='str'){}", errors: [{ messageId: "unexpected", type: "LogicalExpression" }] },
+        { code: "if(true || abc==='str'){}", errors: [{ messageId: "unexpected", type: "LogicalExpression" }] },
+        { code: "if(abc==='str' || true){}", errors: [{ messageId: "unexpected", type: "LogicalExpression" }] },
+        { code: "if(abc==='str' || true || def ==='str'){}", errors: [{ messageId: "unexpected", type: "LogicalExpression" }] },
+        { code: "if(false || true){}", errors: [{ messageId: "unexpected", type: "LogicalExpression" }] },
+        { code: "if(typeof abc==='str' || true){}", errors: [{ messageId: "unexpected", type: "LogicalExpression" }] },
 
         {
             code: "function* foo(){while(true){} yield 'foo';}",
-            errors: [{ message: "Unexpected constant condition.", type: "Literal" }]
+            errors: [{ messageId: "unexpected", type: "Literal" }]
         },
         {
             code: "function* foo(){while(true){if (true) {yield 'foo';}}}",
-            errors: [{ message: "Unexpected constant condition.", type: "Literal" }]
+            errors: [{ messageId: "unexpected", type: "Literal" }]
         },
         {
             code: "function* foo(){while(true){yield 'foo';} while(true) {}}",
-            errors: [{ message: "Unexpected constant condition.", type: "Literal" }]
+            errors: [{ messageId: "unexpected", type: "Literal" }]
         },
         {
             code: "var a = function* foo(){while(true){} yield 'foo';}",
-            errors: [{ message: "Unexpected constant condition.", type: "Literal" }]
+            errors: [{ messageId: "unexpected", type: "Literal" }]
         },
         {
             code: "while (true) { function* foo() {yield;}}",
-            errors: [{ message: "Unexpected constant condition.", type: "Literal" }]
+            errors: [{ messageId: "unexpected", type: "Literal" }]
         },
         {
             code: "function* foo(){if (true) {yield 'foo';}}",
-            errors: [{ message: "Unexpected constant condition.", type: "Literal" }]
+            errors: [{ messageId: "unexpected", type: "Literal" }]
         },
         {
             code: "function* foo() {for (let foo = yield; true;) {}}",
-            errors: [{ message: "Unexpected constant condition.", type: "Literal" }]
+            errors: [{ messageId: "unexpected", type: "Literal" }]
         },
         {
             code: "function* foo() {for (foo = yield; true;) {}}",
-            errors: [{ message: "Unexpected constant condition.", type: "Literal" }]
+            errors: [{ messageId: "unexpected", type: "Literal" }]
         },
         {
             code: "function foo() {while (true) {function* bar() {while (true) {yield;}}}}",
-            errors: [{ message: "Unexpected constant condition.", type: "Literal" }]
+            errors: [{ messageId: "unexpected", type: "Literal" }]
         },
         {
             code: "function* foo() { for (let foo = 1 + 2 + 3 + (yield); true; baz) {}}",
-            errors: [{ message: "Unexpected constant condition.", type: "Literal" }]
+            errors: [{ messageId: "unexpected", type: "Literal" }]
         }
     ]
 });
diff --git a/tests/lib/rules/no-continue.js b/tests/lib/rules/no-continue.js
index 16ed522829f..12e5baf69d3 100644
--- a/tests/lib/rules/no-continue.js
+++ b/tests/lib/rules/no-continue.js
@@ -28,28 +28,28 @@ ruleTester.run("no-continue", rule, {
         {
             code: "var sum = 0, i; for(i = 0; i < 10; i++){ if(i <= 5) { continue; } sum += i; }",
             errors: [{
-                message: "Unexpected use of continue statement.",
+                messageId: "unexpected",
                 type: "ContinueStatement"
             }]
         },
         {
             code: "var sum = 0, i; myLabel: for(i = 0; i < 10; i++){ if(i <= 5) { continue myLabel; } sum += i; }",
             errors: [{
-                message: "Unexpected use of continue statement.",
+                messageId: "unexpected",
                 type: "ContinueStatement"
             }]
         },
         {
             code: "var sum = 0, i = 0; while(i < 10) { if(i <= 5) { i++; continue; } sum += i; i++; }",
             errors: [{
-                message: "Unexpected use of continue statement.",
+                messageId: "unexpected",
                 type: "ContinueStatement"
             }]
         },
         {
             code: "var sum = 0, i = 0; myLabel: while(i < 10) { if(i <= 5) { i++; continue myLabel; } sum += i; i++; }",
             errors: [{
-                message: "Unexpected use of continue statement.",
+                messageId: "unexpected",
                 type: "ContinueStatement"
             }]
         }
diff --git a/tests/lib/rules/no-control-regex.js b/tests/lib/rules/no-control-regex.js
index caa052335db..ebadafc3001 100644
--- a/tests/lib/rules/no-control-regex.js
+++ b/tests/lib/rules/no-control-regex.js
@@ -29,13 +29,13 @@ ruleTester.run("no-control-regex", rule, {
         "new (function foo(){})('\\x1f')"
     ],
     invalid: [
-        { code: `var regex = ${/\x1f/}`, errors: [{ message: "Unexpected control character(s) in regular expression: \\x1f.", type: "Literal" }] }, // eslint-disable-line no-control-regex
-        { code: `var regex = ${/\\\x1f\\x1e/}`, errors: [{ message: "Unexpected control character(s) in regular expression: \\x1f, \\x1e.", type: "Literal" }] }, // eslint-disable-line no-control-regex
-        { code: `var regex = ${/\\\x1fFOO\\x00/}`, errors: [{ message: "Unexpected control character(s) in regular expression: \\x1f, \\x00.", type: "Literal" }] }, // eslint-disable-line no-control-regex
-        { code: `var regex = ${/FOO\\\x1fFOO\\x1f/}`, errors: [{ message: "Unexpected control character(s) in regular expression: \\x1f, \\x1f.", type: "Literal" }] }, // eslint-disable-line no-control-regex
-        { code: "var regex = new RegExp('\\x1f\\x1e')", errors: [{ message: "Unexpected control character(s) in regular expression: \\x1f, \\x1e.", type: "Literal" }] },
-        { code: "var regex = new RegExp('\\x1fFOO\\x00')", errors: [{ message: "Unexpected control character(s) in regular expression: \\x1f, \\x00.", type: "Literal" }] },
-        { code: "var regex = new RegExp('FOO\\x1fFOO\\x1f')", errors: [{ message: "Unexpected control character(s) in regular expression: \\x1f, \\x1f.", type: "Literal" }] },
-        { code: "var regex = RegExp('\\x1f')", errors: [{ message: "Unexpected control character(s) in regular expression: \\x1f.", type: "Literal" }] }
+        { code: `var regex = ${/\x1f/}`, errors: [{ messageId: "unexpected", data: { controlChars: "\\x1f" }, type: "Literal" }] }, // eslint-disable-line no-control-regex
+        { code: `var regex = ${/\\\x1f\\x1e/}`, errors: [{ messageId: "unexpected", data: { controlChars: "\\x1f, \\x1e" }, type: "Literal" }] }, // eslint-disable-line no-control-regex
+        { code: `var regex = ${/\\\x1fFOO\\x00/}`, errors: [{ messageId: "unexpected", data: { controlChars: "\\x1f, \\x00" }, type: "Literal" }] }, // eslint-disable-line no-control-regex
+        { code: `var regex = ${/FOO\\\x1fFOO\\x1f/}`, errors: [{ messageId: "unexpected", data: { controlChars: "\\x1f, \\x1f" }, type: "Literal" }] }, // eslint-disable-line no-control-regex
+        { code: "var regex = new RegExp('\\x1f\\x1e')", errors: [{ messageId: "unexpected", data: { controlChars: "\\x1f, \\x1e" }, type: "Literal" }] },
+        { code: "var regex = new RegExp('\\x1fFOO\\x00')", errors: [{ messageId: "unexpected", data: { controlChars: "\\x1f, \\x00" }, type: "Literal" }] },
+        { code: "var regex = new RegExp('FOO\\x1fFOO\\x1f')", errors: [{ messageId: "unexpected", data: { controlChars: "\\x1f, \\x1f" }, type: "Literal" }] },
+        { code: "var regex = RegExp('\\x1f')", errors: [{ messageId: "unexpected", data: { controlChars: "\\x1f" }, type: "Literal" }] }
     ]
 });
diff --git a/tests/lib/rules/no-debugger.js b/tests/lib/rules/no-debugger.js
index 9edf059c41e..d977505999f 100644
--- a/tests/lib/rules/no-debugger.js
+++ b/tests/lib/rules/no-debugger.js
@@ -26,12 +26,12 @@ ruleTester.run("no-debugger", rule, {
         {
             code: "debugger",
             output: "",
-            errors: [{ message: "Unexpected 'debugger' statement.", type: "DebuggerStatement" }]
+            errors: [{ messageId: "unexpected", type: "DebuggerStatement" }]
         },
         {
             code: "if (foo) debugger",
             output: null,
-            errors: [{ message: "Unexpected 'debugger' statement.", type: "DebuggerStatement" }]
+            errors: [{ messageId: "unexpected", type: "DebuggerStatement" }]
         }
     ]
 });
diff --git a/tests/lib/rules/no-delete-var.js b/tests/lib/rules/no-delete-var.js
index 7e94c7f9ea9..ec284923e33 100644
--- a/tests/lib/rules/no-delete-var.js
+++ b/tests/lib/rules/no-delete-var.js
@@ -23,6 +23,6 @@ ruleTester.run("no-delete-var", rule, {
         "delete x.prop;"
     ],
     invalid: [
-        { code: "delete x", errors: [{ message: "Variables should not be deleted.", type: "UnaryExpression" }] }
+        { code: "delete x", errors: [{ messageId: "unexpected", type: "UnaryExpression" }] }
     ]
 });
diff --git a/tests/lib/rules/no-div-regex.js b/tests/lib/rules/no-div-regex.js
index 46881b363c6..fbad6a61886 100644
--- a/tests/lib/rules/no-div-regex.js
+++ b/tests/lib/rules/no-div-regex.js
@@ -24,6 +24,6 @@ ruleTester.run("no-div-regex", rule, {
         "var f = function() { return /\\=foo/; };"
     ],
     invalid: [
-        { code: "var f = function() { return /=foo/; };", errors: [{ message: "A regular expression literal can be confused with '/='.", type: "Literal" }] }
+        { code: "var f = function() { return /=foo/; };", errors: [{ messageId: "unexpected", type: "Literal" }] }
     ]
 });
diff --git a/tests/lib/rules/no-dupe-args.js b/tests/lib/rules/no-dupe-args.js
index b323fbe6ba0..829a6d81e65 100644
--- a/tests/lib/rules/no-dupe-args.js
+++ b/tests/lib/rules/no-dupe-args.js
@@ -27,13 +27,13 @@ ruleTester.run("no-dupe-args", rule, {
         { code: "function foo([[a, b], [c, d]]) {}", parserOptions: { ecmaVersion: 6 } }
     ],
     invalid: [
-        { code: "function a(a, b, b) {}", errors: [{ message: "Duplicate param 'b'." }] },
-        { code: "function a(a, a, a) {}", errors: [{ message: "Duplicate param 'a'." }] },
-        { code: "function a(a, b, a) {}", errors: [{ message: "Duplicate param 'a'." }] },
-        { code: "function a(a, b, a, b) {}", errors: [{ message: "Duplicate param 'a'." }, { message: "Duplicate param 'b'." }] },
-        { code: "var a = function(a, b, b) {}", errors: [{ message: "Duplicate param 'b'." }] },
-        { code: "var a = function(a, a, a) {}", errors: [{ message: "Duplicate param 'a'." }] },
-        { code: "var a = function(a, b, a) {}", errors: [{ message: "Duplicate param 'a'." }] },
-        { code: "var a = function(a, b, a, b) {}", errors: [{ message: "Duplicate param 'a'." }, { message: "Duplicate param 'b'." }] }
+        { code: "function a(a, b, b) {}", errors: [{ messageId: "unexpected", data: { name: "b" } }] },
+        { code: "function a(a, a, a) {}", errors: [{ messageId: "unexpected", data: { name: "a" } }] },
+        { code: "function a(a, b, a) {}", errors: [{ messageId: "unexpected", data: { name: "a" } }] },
+        { code: "function a(a, b, a, b) {}", errors: [{ messageId: "unexpected", data: { name: "a" } }, { messageId: "unexpected", data: { name: "b" } }] },
+        { code: "var a = function(a, b, b) {}", errors: [{ messageId: "unexpected", data: { name: "b" } }] },
+        { code: "var a = function(a, a, a) {}", errors: [{ messageId: "unexpected", data: { name: "a" } }] },
+        { code: "var a = function(a, b, a) {}", errors: [{ messageId: "unexpected", data: { name: "a" } }] },
+        { code: "var a = function(a, b, a, b) {}", errors: [{ messageId: "unexpected", data: { name: "a" } }, { messageId: "unexpected", data: { name: "b" } }] }
     ]
 });
diff --git a/tests/lib/rules/no-dupe-class-members.js b/tests/lib/rules/no-dupe-class-members.js
index 24eb2e53701..0c79dfb6242 100644
--- a/tests/lib/rules/no-dupe-class-members.js
+++ b/tests/lib/rules/no-dupe-class-members.js
@@ -35,50 +35,50 @@ ruleTester.run("no-dupe-class-members", rule, {
         {
             code: "class A { foo() {} foo() {} }",
             errors: [
-                { type: "MethodDefinition", line: 1, column: 20, message: "Duplicate name 'foo'." }
+                { type: "MethodDefinition", line: 1, column: 20, messageId: "unexpected", data: { name: "foo" } }
             ]
         },
         {
             code: "!class A { foo() {} foo() {} };",
             errors: [
-                { type: "MethodDefinition", line: 1, column: 21, message: "Duplicate name 'foo'." }
+                { type: "MethodDefinition", line: 1, column: 21, messageId: "unexpected", data: { name: "foo" } }
             ]
         },
         {
             code: "class A { 'foo'() {} 'foo'() {} }",
             errors: [
-                { type: "MethodDefinition", line: 1, column: 22, message: "Duplicate name 'foo'." }
+                { type: "MethodDefinition", line: 1, column: 22, messageId: "unexpected", data: { name: "foo" } }
             ]
         },
         {
             code: "class A { 10() {} 1e1() {} }",
             errors: [
-                { type: "MethodDefinition", line: 1, column: 19, message: "Duplicate name '10'." }
+                { type: "MethodDefinition", line: 1, column: 19, messageId: "unexpected", data: { name: "10" } }
             ]
         },
         {
             code: "class A { foo() {} foo() {} foo() {} }",
             errors: [
-                { type: "MethodDefinition", line: 1, column: 20, message: "Duplicate name 'foo'." },
-                { type: "MethodDefinition", line: 1, column: 29, message: "Duplicate name 'foo'." }
+                { type: "MethodDefinition", line: 1, column: 20, messageId: "unexpected", data: { name: "foo" } },
+                { type: "MethodDefinition", line: 1, column: 29, messageId: "unexpected", data: { name: "foo" } }
             ]
         },
         {
             code: "class A { static foo() {} static foo() {} }",
             errors: [
-                { type: "MethodDefinition", line: 1, column: 27, message: "Duplicate name 'foo'." }
+                { type: "MethodDefinition", line: 1, column: 27, messageId: "unexpected", data: { name: "foo" } }
             ]
         },
         {
             code: "class A { foo() {} get foo() {} }",
             errors: [
-                { type: "MethodDefinition", line: 1, column: 20, message: "Duplicate name 'foo'." }
+                { type: "MethodDefinition", line: 1, column: 20, messageId: "unexpected", data: { name: "foo" } }
             ]
         },
         {
             code: "class A { set foo(value) {} foo() {} }",
             errors: [
-                { type: "MethodDefinition", line: 1, column: 29, message: "Duplicate name 'foo'." }
+                { type: "MethodDefinition", line: 1, column: 29, messageId: "unexpected", data: { name: "foo" } }
             ]
         }
     ]
diff --git a/tests/lib/rules/no-dupe-keys.js b/tests/lib/rules/no-dupe-keys.js
index d06f20c5788..c8ca43b54d4 100644
--- a/tests/lib/rules/no-dupe-keys.js
+++ b/tests/lib/rules/no-dupe-keys.js
@@ -30,13 +30,13 @@ ruleTester.run("no-dupe-keys", rule, {
         { code: "var {a, a} = obj", parserOptions: { ecmaVersion: 6 } }
     ],
     invalid: [
-        { code: "var x = { a: b, ['a']: b };", parserOptions: { ecmaVersion: 6 }, errors: [{ message: "Duplicate key 'a'.", type: "ObjectExpression" }] },
-        { code: "var x = { y: 1, y: 2 };", errors: [{ message: "Duplicate key 'y'.", type: "ObjectExpression" }] },
-        { code: "var foo = { 0x1: 1, 1: 2};", errors: [{ message: "Duplicate key '1'.", type: "ObjectExpression" }] },
-        { code: "var x = { \"z\": 1, z: 2 };", errors: [{ message: "Duplicate key 'z'.", type: "ObjectExpression" }] },
-        { code: "var foo = {\n  bar: 1,\n  bar: 1,\n}", errors: [{ message: "Duplicate key 'bar'.", line: 3, column: 3 }] },
-        { code: "var x = { a: 1, get a() {} };", parserOptions: { ecmaVersion: 6 }, errors: [{ message: "Duplicate key 'a'.", type: "ObjectExpression" }] },
-        { code: "var x = { a: 1, set a(value) {} };", parserOptions: { ecmaVersion: 6 }, errors: [{ message: "Duplicate key 'a'.", type: "ObjectExpression" }] },
-        { code: "var x = { a: 1, b: { a: 2 }, get b() {} };", parserOptions: { ecmaVersion: 6 }, errors: [{ message: "Duplicate key 'b'.", type: "ObjectExpression" }] }
+        { code: "var x = { a: b, ['a']: b };", parserOptions: { ecmaVersion: 6 }, errors: [{ messageId: "unexpected", data: { name: "a" }, type: "ObjectExpression" }] },
+        { code: "var x = { y: 1, y: 2 };", errors: [{ messageId: "unexpected", data: { name: "y" }, type: "ObjectExpression" }] },
+        { code: "var foo = { 0x1: 1, 1: 2};", errors: [{ messageId: "unexpected", data: { name: "1" }, type: "ObjectExpression" }] },
+        { code: "var x = { \"z\": 1, z: 2 };", errors: [{ messageId: "unexpected", data: { name: "z" }, type: "ObjectExpression" }] },
+        { code: "var foo = {\n  bar: 1,\n  bar: 1,\n}", errors: [{ messageId: "unexpected", data: { name: "bar" }, line: 3, column: 3 }] },
+        { code: "var x = { a: 1, get a() {} };", parserOptions: { ecmaVersion: 6 }, errors: [{ messageId: "unexpected", data: { name: "a" }, type: "ObjectExpression" }] },
+        { code: "var x = { a: 1, set a(value) {} };", parserOptions: { ecmaVersion: 6 }, errors: [{ messageId: "unexpected", data: { name: "a" }, type: "ObjectExpression" }] },
+        { code: "var x = { a: 1, b: { a: 2 }, get b() {} };", parserOptions: { ecmaVersion: 6 }, errors: [{ messageId: "unexpected", data: { name: "b" }, type: "ObjectExpression" }] }
     ]
 });
diff --git a/tests/lib/rules/no-duplicate-case.js b/tests/lib/rules/no-duplicate-case.js
index c265dca1030..c01085e0420 100644
--- a/tests/lib/rules/no-duplicate-case.js
+++ b/tests/lib/rules/no-duplicate-case.js
@@ -35,63 +35,63 @@ ruleTester.run("no-duplicate-case", rule, {
         {
             code: "var a = 1; switch (a) {case 1: break; case 1: break; case 2: break; default: break;}",
             errors: [{
-                message: "Duplicate case label.",
+                messageId: "unexpected",
                 type: "SwitchCase"
             }]
         },
         {
             code: "var a = '1'; switch (a) {case '1': break; case '1': break; case '2': break; default: break;}",
             errors: [{
-                message: "Duplicate case label.",
+                messageId: "unexpected",
                 type: "SwitchCase"
             }]
         },
         {
             code: "var a = 1, one = 1; switch (a) {case one: break; case one: break; case 2: break; default: break;}",
             errors: [{
-                message: "Duplicate case label.",
+                messageId: "unexpected",
                 type: "SwitchCase"
             }]
         },
         {
             code: "var a = 1, p = {p: {p1: 1, p2: 1}}; switch (a) {case p.p.p1: break; case p.p.p1: break; default: break;}",
             errors: [{
-                message: "Duplicate case label.",
+                messageId: "unexpected",
                 type: "SwitchCase"
             }]
         },
         {
             code: "var a = 1, f = function(b) { return b ? { p1: 1 } : { p1: 2 }; }; switch (a) {case f(true).p1: break; case f(true).p1: break; default: break;}",
             errors: [{
-                message: "Duplicate case label.",
+                messageId: "unexpected",
                 type: "SwitchCase"
             }]
         },
         {
             code: "var a = 1, f = function(s) { return { p1: s } }; switch (a) {case f(a + 1).p1: break; case f(a + 1).p1: break; default: break;}",
             errors: [{
-                message: "Duplicate case label.",
+                messageId: "unexpected",
                 type: "SwitchCase"
             }]
         },
         {
             code: "var a = 1, f = function(s) { return { p1: s } }; switch (a) {case f(a === 1 ? 2 : 3).p1: break; case f(a === 1 ? 2 : 3).p1: break; default: break;}",
             errors: [{
-                message: "Duplicate case label.",
+                messageId: "unexpected",
                 type: "SwitchCase"
             }]
         },
         {
             code: "var a = 1, f1 = function() { return { p1: 1 } }; switch (a) {case f1().p1: break; case f1().p1: break; default: break;}",
             errors: [{
-                message: "Duplicate case label.",
+                messageId: "unexpected",
                 type: "SwitchCase"
             }]
         },
         {
             code: "var a = [1, 2]; switch(a.toString()){case ([1, 2]).toString():break; case ([1, 2]).toString():break; default:break;}",
             errors: [{
-                message: "Duplicate case label.",
+                messageId: "unexpected",
                 type: "SwitchCase"
             }]
         }
diff --git a/tests/lib/rules/no-else-return.js b/tests/lib/rules/no-else-return.js
index f88407151f2..6111b55da65 100644
--- a/tests/lib/rules/no-else-return.js
+++ b/tests/lib/rules/no-else-return.js
@@ -60,128 +60,128 @@ ruleTester.run("no-else-return", rule, {
         {
             code: "function foo1() { if (true) { return x; } else { return y; } }",
             output: "function foo1() { if (true) { return x; }  return y;  }",
-            errors: [{ message: "Unnecessary 'else' after 'return'.", type: "BlockStatement" }]
+            errors: [{ messageId: "unexpected", type: "BlockStatement" }]
         },
         {
             code: "function foo2() { if (true) { var x = bar; return x; } else { var y = baz; return y; } }",
             output: "function foo2() { if (true) { var x = bar; return x; }  var y = baz; return y;  }",
-            errors: [{ message: "Unnecessary 'else' after 'return'.", type: "BlockStatement" }]
+            errors: [{ messageId: "unexpected", type: "BlockStatement" }]
         },
         {
             code: "function foo3() { if (true) return x; else return y; }",
             output: "function foo3() { if (true) return x; return y; }",
-            errors: [{ message: "Unnecessary 'else' after 'return'.", type: "ReturnStatement" }]
+            errors: [{ messageId: "unexpected", type: "ReturnStatement" }]
         },
         {
             code: "function foo4() { if (true) { if (false) return x; else return y; } else { return z; } }",
             output: "function foo4() { if (true) { if (false) return x; return y; } else { return z; } }", // Other case is fixed in the second pass.
-            errors: [{ message: "Unnecessary 'else' after 'return'.", type: "ReturnStatement" }, { message: "Unnecessary 'else' after 'return'.", type: "BlockStatement" }]
+            errors: [{ messageId: "unexpected", type: "ReturnStatement" }, { messageId: "unexpected", type: "BlockStatement" }]
         },
         {
             code: "function foo5() { if (true) { if (false) { if (true) return x; else { w = y; } } else { w = x; } } else { return z; } }",
             output: "function foo5() { if (true) { if (false) { if (true) return x;  w = y;  } else { w = x; } } else { return z; } }",
-            errors: [{ message: "Unnecessary 'else' after 'return'.", type: "BlockStatement" }]
+            errors: [{ messageId: "unexpected", type: "BlockStatement" }]
         },
         {
             code: "function foo6() { if (true) { if (false) { if (true) return x; else return y; } } else { return z; } }",
             output: "function foo6() { if (true) { if (false) { if (true) return x; return y; } } else { return z; } }",
-            errors: [{ message: "Unnecessary 'else' after 'return'.", type: "ReturnStatement" }]
+            errors: [{ messageId: "unexpected", type: "ReturnStatement" }]
         },
         {
             code: "function foo7() { if (true) { if (false) { if (true) return x; else return y; } return w; } else { return z; } }",
             output: "function foo7() { if (true) { if (false) { if (true) return x; return y; } return w; } else { return z; } }", // Other case is fixed in the second pass.
             errors: [
-                { message: "Unnecessary 'else' after 'return'.", type: "ReturnStatement" },
-                { message: "Unnecessary 'else' after 'return'.", type: "BlockStatement" }
+                { messageId: "unexpected", type: "ReturnStatement" },
+                { messageId: "unexpected", type: "BlockStatement" }
             ]
         },
         {
             code: "function foo8() { if (true) { if (false) { if (true) return x; else return y; } else { w = x; } } else { return z; } }",
             output: "function foo8() { if (true) { if (false) { if (true) return x; return y; } else { w = x; } } else { return z; } }", // Other case is fixed in the second pass.
             errors: [
-                { message: "Unnecessary 'else' after 'return'.", type: "ReturnStatement" },
-                { message: "Unnecessary 'else' after 'return'.", type: "BlockStatement" }
+                { messageId: "unexpected", type: "ReturnStatement" },
+                { messageId: "unexpected", type: "BlockStatement" }
             ]
         },
         {
             code: "function foo9() {if (x) { return true; } else if (y) { return true; } else { notAReturn(); } }",
             output: "function foo9() {if (x) { return true; } else if (y) { return true; }  notAReturn();  }",
-            errors: [{ message: "Unnecessary 'else' after 'return'.", type: "BlockStatement" }]
+            errors: [{ messageId: "unexpected", type: "BlockStatement" }]
         },
         {
             code: "function foo9a() {if (x) { return true; } else if (y) { return true; } else { notAReturn(); } }",
             output: "function foo9a() {if (x) { return true; } if (y) { return true; } else { notAReturn(); } }",
             options: [{ allowElseIf: false }],
-            errors: [{ message: "Unnecessary 'else' after 'return'.", type: "IfStatement" }]
+            errors: [{ messageId: "unexpected", type: "IfStatement" }]
         },
         {
             code: "function foo9b() {if (x) { return true; } if (y) { return true; } else { notAReturn(); } }",
             output: "function foo9b() {if (x) { return true; } if (y) { return true; }  notAReturn();  }",
             options: [{ allowElseIf: false }],
-            errors: [{ message: "Unnecessary 'else' after 'return'.", type: "BlockStatement" }]
+            errors: [{ messageId: "unexpected", type: "BlockStatement" }]
         },
         {
             code: "function foo10() { if (foo) return bar; else (foo).bar(); }",
             output: "function foo10() { if (foo) return bar; (foo).bar(); }",
-            errors: [{ message: "Unnecessary 'else' after 'return'.", type: "ExpressionStatement" }]
+            errors: [{ messageId: "unexpected", type: "ExpressionStatement" }]
         },
         {
             code: "function foo11() { if (foo) return bar \nelse { [1, 2, 3].map(foo) } }",
             output: null,
-            errors: [{ message: "Unnecessary 'else' after 'return'.", type: "BlockStatement" }]
+            errors: [{ messageId: "unexpected", type: "BlockStatement" }]
         },
         {
             code: "function foo12() { if (foo) return bar \nelse { baz() } \n[1, 2, 3].map(foo) }",
             output: null,
-            errors: [{ message: "Unnecessary 'else' after 'return'.", type: "BlockStatement" }]
+            errors: [{ messageId: "unexpected", type: "BlockStatement" }]
         },
         {
             code: "function foo13() { if (foo) return bar; \nelse { [1, 2, 3].map(foo) } }",
             output: "function foo13() { if (foo) return bar; \n [1, 2, 3].map(foo)  }",
-            errors: [{ message: "Unnecessary 'else' after 'return'.", type: "BlockStatement" }]
+            errors: [{ messageId: "unexpected", type: "BlockStatement" }]
         },
         {
             code: "function foo14() { if (foo) return bar \nelse { baz(); } \n[1, 2, 3].map(foo) }",
             output: "function foo14() { if (foo) return bar \n baz();  \n[1, 2, 3].map(foo) }",
-            errors: [{ message: "Unnecessary 'else' after 'return'.", type: "BlockStatement" }]
+            errors: [{ messageId: "unexpected", type: "BlockStatement" }]
         },
         {
             code: "function foo15() { if (foo) return bar; else { baz() } qaz() }",
             output: null,
-            errors: [{ message: "Unnecessary 'else' after 'return'.", type: "BlockStatement" }]
+            errors: [{ messageId: "unexpected", type: "BlockStatement" }]
         },
         {
             code: "function foo16() { if (foo) return bar \nelse { baz() } qaz() }",
             output: null,
-            errors: [{ message: "Unnecessary 'else' after 'return'.", type: "BlockStatement" }]
+            errors: [{ messageId: "unexpected", type: "BlockStatement" }]
         },
         {
             code: "function foo17() { if (foo) return bar \nelse { baz() } \nqaz() }",
             output: "function foo17() { if (foo) return bar \n baz()  \nqaz() }",
-            errors: [{ message: "Unnecessary 'else' after 'return'.", type: "BlockStatement" }]
+            errors: [{ messageId: "unexpected", type: "BlockStatement" }]
         },
         {
             code: "function foo18() { if (foo) return function() {} \nelse [1, 2, 3].map(bar) }",
             output: null,
-            errors: [{ message: "Unnecessary 'else' after 'return'.", type: "ExpressionStatement" }]
+            errors: [{ messageId: "unexpected", type: "ExpressionStatement" }]
         },
         {
             code: "function foo19() { if (true) { return x; } else if (false) { return y; } }",
             output: "function foo19() { if (true) { return x; } if (false) { return y; } }",
             options: [{ allowElseIf: false }],
-            errors: [{ message: "Unnecessary 'else' after 'return'.", type: "IfStatement" }]
+            errors: [{ messageId: "unexpected", type: "IfStatement" }]
         },
         {
             code: "function foo20() {if (x) { return true; } else if (y) { notAReturn() } else { notAReturn(); } }",
             output: "function foo20() {if (x) { return true; } if (y) { notAReturn() } else { notAReturn(); } }",
             options: [{ allowElseIf: false }],
-            errors: [{ message: "Unnecessary 'else' after 'return'.", type: "IfStatement" }]
+            errors: [{ messageId: "unexpected", type: "IfStatement" }]
         },
         {
             code: "function foo21() { var x = true; if (x) { return x; } else if (x === false) { return false; } }",
             output: "function foo21() { var x = true; if (x) { return x; } if (x === false) { return false; } }",
             options: [{ allowElseIf: false }],
-            errors: [{ message: "Unnecessary 'else' after 'return'.", type: "IfStatement" }]
+            errors: [{ messageId: "unexpected", type: "IfStatement" }]
         }
     ]
 });
diff --git a/tests/lib/rules/no-empty-character-class.js b/tests/lib/rules/no-empty-character-class.js
index d72eb3ca661..ce81e5488e6 100644
--- a/tests/lib/rules/no-empty-character-class.js
+++ b/tests/lib/rules/no-empty-character-class.js
@@ -33,12 +33,12 @@ ruleTester.run("no-empty-character-class", rule, {
         { code: "var foo = /[\\]]/uy;", parserOptions: { ecmaVersion: 6 } }
     ],
     invalid: [
-        { code: "var foo = /^abc[]/;", errors: [{ message: "Empty class.", type: "Literal" }] },
-        { code: "var foo = /foo[]bar/;", errors: [{ message: "Empty class.", type: "Literal" }] },
-        { code: "if (foo.match(/^abc[]/)) {}", errors: [{ message: "Empty class.", type: "Literal" }] },
-        { code: "if (/^abc[]/.test(foo)) {}", errors: [{ message: "Empty class.", type: "Literal" }] },
-        { code: "var foo = /[]]/;", errors: [{ message: "Empty class.", type: "Literal" }] },
-        { code: "var foo = /\\[[]/;", errors: [{ message: "Empty class.", type: "Literal" }] },
-        { code: "var foo = /\\[\\[\\]a-z[]/;", errors: [{ message: "Empty class.", type: "Literal" }] }
+        { code: "var foo = /^abc[]/;", errors: [{ messageId: "unexpected", type: "Literal" }] },
+        { code: "var foo = /foo[]bar/;", errors: [{ messageId: "unexpected", type: "Literal" }] },
+        { code: "if (foo.match(/^abc[]/)) {}", errors: [{ messageId: "unexpected", type: "Literal" }] },
+        { code: "if (/^abc[]/.test(foo)) {}", errors: [{ messageId: "unexpected", type: "Literal" }] },
+        { code: "var foo = /[]]/;", errors: [{ messageId: "unexpected", type: "Literal" }] },
+        { code: "var foo = /\\[[]/;", errors: [{ messageId: "unexpected", type: "Literal" }] },
+        { code: "var foo = /\\[\\[\\]a-z[]/;", errors: [{ messageId: "unexpected", type: "Literal" }] }
     ]
 });
diff --git a/tests/lib/rules/no-empty-function.js b/tests/lib/rules/no-empty-function.js
index 5f65f992fbd..416a47da687 100644
--- a/tests/lib/rules/no-empty-function.js
+++ b/tests/lib/rules/no-empty-function.js
@@ -58,10 +58,12 @@ function toValidInvalid(patterns, item) {
         }
     );
 
+    const error = item.message || { messageId: item.messageId, data: item.data };
+
     // Invalid Patterns.
     patterns.invalid.push({
         code: item.code,
-        errors: [item.message],
+        errors: [error],
         parserOptions: { ecmaVersion: 6 }
     });
     ALLOW_OPTIONS
@@ -71,7 +73,7 @@ function toValidInvalid(patterns, item) {
             // non related "allow" option has no effect.
             patterns.invalid.push({
                 code: `${item.code} // allow: ${allow}`,
-                errors: [item.message],
+                errors: [error],
                 options: [{ allow: [allow] }],
                 parserOptions: { ecmaVersion: 6 }
             });
@@ -89,147 +91,176 @@ const ruleTester = new RuleTester();
 ruleTester.run("no-empty-function", rule, [
     {
         code: "function foo() {}",
-        message: "Unexpected empty function 'foo'.",
+        messageId: "unexpected",
+        data: { name: "function 'foo'" },
         allow: "functions"
     },
     {
         code: "var foo = function() {};",
-        message: "Unexpected empty function.",
+        messageId: "unexpected",
+        data: { name: "function" },
         allow: "functions"
     },
     {
         code: "var obj = {foo: function() {}};",
-        message: "Unexpected empty method 'foo'.",
+        messageId: "unexpected",
+        data: { name: "method 'foo'" },
         allow: "functions"
     },
     {
         code: "var foo = () => {};",
-        message: "Unexpected empty arrow function.",
+        messageId: "unexpected",
+        data: { name: "arrow function" },
         allow: "arrowFunctions"
     },
     {
         code: "function* foo() {}",
-        message: "Unexpected empty generator function 'foo'.",
+        messageId: "unexpected",
+        data: { name: "generator function 'foo'" },
         allow: "generatorFunctions"
     },
     {
         code: "var foo = function*() {};",
-        message: "Unexpected empty generator function.",
+        messageId: "unexpected",
+        data: { name: "generator function" },
         allow: "generatorFunctions"
     },
     {
         code: "var obj = {foo: function*() {}};",
-        message: "Unexpected empty generator method 'foo'.",
+        messageId: "unexpected",
+        data: { name: "generator method 'foo'" },
         allow: "generatorFunctions"
     },
     {
         code: "var obj = {foo() {}};",
-        message: "Unexpected empty method 'foo'.",
+        messageId: "unexpected",
+        data: { name: "method 'foo'" },
         allow: "methods"
     },
     {
         code: "class A {foo() {}}",
-        message: "Unexpected empty method 'foo'.",
+        messageId: "unexpected",
+        data: { name: "method 'foo'" },
         allow: "methods"
     },
     {
         code: "class A {static foo() {}}",
-        message: "Unexpected empty static method 'foo'.",
+        messageId: "unexpected",
+        data: { name: "static method 'foo'" },
         allow: "methods"
     },
     {
         code: "var A = class {foo() {}};",
-        message: "Unexpected empty method 'foo'.",
+        messageId: "unexpected",
+        data: { name: "method 'foo'" },
         allow: "methods"
     },
     {
         code: "var A = class {static foo() {}};",
-        message: "Unexpected empty static method 'foo'.",
+        messageId: "unexpected",
+        data: { name: "static method 'foo'" },
         allow: "methods"
     },
     {
         code: "var obj = {*foo() {}};",
-        message: "Unexpected empty generator method 'foo'.",
+        messageId: "unexpected",
+        data: { name: "generator method 'foo'" },
         allow: "generatorMethods"
     },
     {
         code: "class A {*foo() {}}",
-        message: "Unexpected empty generator method 'foo'.",
+        messageId: "unexpected",
+        data: { name: "generator method 'foo'" },
         allow: "generatorMethods"
     },
     {
         code: "class A {static *foo() {}}",
-        message: "Unexpected empty static generator method 'foo'.",
+        messageId: "unexpected",
+        data: { name: "static generator method 'foo'" },
         allow: "generatorMethods"
     },
     {
         code: "var A = class {*foo() {}};",
-        message: "Unexpected empty generator method 'foo'.",
+        messageId: "unexpected",
+        data: { name: "generator method 'foo'" },
         allow: "generatorMethods"
     },
     {
         code: "var A = class {static *foo() {}};",
-        message: "Unexpected empty static generator method 'foo'.",
+        messageId: "unexpected",
+        data: { name: "static generator method 'foo'" },
         allow: "generatorMethods"
     },
     {
         code: "var obj = {get foo() {}};",
-        message: "Unexpected empty getter 'foo'.",
+        messageId: "unexpected",
+        data: { name: "getter 'foo'" },
         allow: "getters"
     },
     {
         code: "class A {get foo() {}}",
-        message: "Unexpected empty getter 'foo'.",
+        messageId: "unexpected",
+        data: { name: "getter 'foo'" },
         allow: "getters"
     },
     {
         code: "class A {static get foo() {}}",
-        message: "Unexpected empty static getter 'foo'.",
+        messageId: "unexpected",
+        data: { name: "static getter 'foo'" },
         allow: "getters"
     },
     {
         code: "var A = class {get foo() {}};",
-        message: "Unexpected empty getter 'foo'.",
+        messageId: "unexpected",
+        data: { name: "getter 'foo'" },
         allow: "getters"
     },
     {
         code: "var A = class {static get foo() {}};",
-        message: "Unexpected empty static getter 'foo'.",
+        messageId: "unexpected",
+        data: { name: "static getter 'foo'" },
         allow: "getters"
     },
     {
         code: "var obj = {set foo(value) {}};",
-        message: "Unexpected empty setter 'foo'.",
+        messageId: "unexpected",
+        data: { name: "setter 'foo'" },
         allow: "setters"
     },
     {
         code: "class A {set foo(value) {}}",
-        message: "Unexpected empty setter 'foo'.",
+        messageId: "unexpected",
+        data: { name: "setter 'foo'" },
         allow: "setters"
     },
     {
         code: "class A {static set foo(value) {}}",
-        message: "Unexpected empty static setter 'foo'.",
+        messageId: "unexpected",
+        data: { name: "static setter 'foo'" },
         allow: "setters"
     },
     {
         code: "var A = class {set foo(value) {}};",
-        message: "Unexpected empty setter 'foo'.",
+        messageId: "unexpected",
+        data: { name: "setter 'foo'" },
         allow: "setters"
     },
     {
         code: "var A = class {static set foo(value) {}};",
-        message: "Unexpected empty static setter 'foo'.",
+        messageId: "unexpected",
+        data: { name: "static setter 'foo'" },
         allow: "setters"
     },
     {
         code: "class A {constructor() {}}",
-        message: "Unexpected empty constructor.",
+        messageId: "unexpected",
+        data: { name: "constructor" },
         allow: "constructors"
     },
     {
         code: "var A = class {constructor() {}};",
-        message: "Unexpected empty constructor.",
+        messageId: "unexpected",
+        data: { name: "constructor" },
         allow: "constructors"
     }
 ].reduce(toValidInvalid, {
diff --git a/tests/lib/rules/no-empty-pattern.js b/tests/lib/rules/no-empty-pattern.js
index c3762e55e12..64b32977a6e 100644
--- a/tests/lib/rules/no-empty-pattern.js
+++ b/tests/lib/rules/no-empty-pattern.js
@@ -35,7 +35,8 @@ ruleTester.run("no-empty-pattern", rule, {
             code: "var {} = foo",
             parserOptions: { ecmaVersion: 6 },
             errors: [{
-                message: "Unexpected empty object pattern.",
+                messageId: "unexpected",
+                data: { type: "object" },
                 type: "ObjectPattern"
             }]
         },
@@ -43,7 +44,8 @@ ruleTester.run("no-empty-pattern", rule, {
             code: "var [] = foo",
             parserOptions: { ecmaVersion: 6 },
             errors: [{
-                message: "Unexpected empty array pattern.",
+                messageId: "unexpected",
+                data: { type: "array" },
                 type: "ArrayPattern"
             }]
         },
@@ -51,7 +53,8 @@ ruleTester.run("no-empty-pattern", rule, {
             code: "var {a: {}} = foo",
             parserOptions: { ecmaVersion: 6 },
             errors: [{
-                message: "Unexpected empty object pattern.",
+                messageId: "unexpected",
+                data: { type: "object" },
                 type: "ObjectPattern"
             }]
         },
@@ -59,7 +62,8 @@ ruleTester.run("no-empty-pattern", rule, {
             code: "var {a, b: {}} = foo",
             parserOptions: { ecmaVersion: 6 },
             errors: [{
-                message: "Unexpected empty object pattern.",
+                messageId: "unexpected",
+                data: { type: "object" },
                 type: "ObjectPattern"
             }]
         },
@@ -67,7 +71,8 @@ ruleTester.run("no-empty-pattern", rule, {
             code: "var {a: []} = foo",
             parserOptions: { ecmaVersion: 6 },
             errors: [{
-                message: "Unexpected empty array pattern.",
+                messageId: "unexpected",
+                data: { type: "array" },
                 type: "ArrayPattern"
             }]
         },
@@ -75,7 +80,8 @@ ruleTester.run("no-empty-pattern", rule, {
             code: "function foo({}) {}",
             parserOptions: { ecmaVersion: 6 },
             errors: [{
-                message: "Unexpected empty object pattern.",
+                messageId: "unexpected",
+                data: { type: "object" },
                 type: "ObjectPattern"
             }]
         },
@@ -83,7 +89,8 @@ ruleTester.run("no-empty-pattern", rule, {
             code: "function foo([]) {}",
             parserOptions: { ecmaVersion: 6 },
             errors: [{
-                message: "Unexpected empty array pattern.",
+                messageId: "unexpected",
+                data: { type: "array" },
                 type: "ArrayPattern"
             }]
         },
@@ -91,7 +98,8 @@ ruleTester.run("no-empty-pattern", rule, {
             code: "function foo({a: {}}) {}",
             parserOptions: { ecmaVersion: 6 },
             errors: [{
-                message: "Unexpected empty object pattern.",
+                messageId: "unexpected",
+                data: { type: "object" },
                 type: "ObjectPattern"
             }]
         },
@@ -99,7 +107,8 @@ ruleTester.run("no-empty-pattern", rule, {
             code: "function foo({a: []}) {}",
             parserOptions: { ecmaVersion: 6 },
             errors: [{
-                message: "Unexpected empty array pattern.",
+                messageId: "unexpected",
+                data: { type: "array" },
                 type: "ArrayPattern"
             }]
         }
diff --git a/tests/lib/rules/no-empty.js b/tests/lib/rules/no-empty.js
index 61741f007bd..8706b276f95 100644
--- a/tests/lib/rules/no-empty.js
+++ b/tests/lib/rules/no-empty.js
@@ -44,36 +44,36 @@ ruleTester.run("no-empty", rule, {
         { code: "try { foo(); } catch (ex) {} finally { bar(); }", options: [{ allowEmptyCatch: true }] }
     ],
     invalid: [
-        { code: "try {} catch (ex) {throw ex}", errors: [{ message: "Empty block statement.", type: "BlockStatement" }] },
-        { code: "try { foo() } catch (ex) {}", errors: [{ message: "Empty block statement.", type: "BlockStatement" }] },
-        { code: "try { foo() } catch (ex) {throw ex} finally {}", errors: [{ message: "Empty block statement.", type: "BlockStatement" }] },
-        { code: "if (foo) {}", errors: [{ message: "Empty block statement.", type: "BlockStatement" }] },
-        { code: "while (foo) {}", errors: [{ message: "Empty block statement.", type: "BlockStatement" }] },
-        { code: "for (;foo;) {}", errors: [{ message: "Empty block statement.", type: "BlockStatement" }] },
-        { code: "switch(foo) {}", errors: [{ message: "Empty switch statement.", type: "SwitchStatement" }] },
+        { code: "try {} catch (ex) {throw ex}", errors: [{ messageId: "unexpected", data: { type: "block" }, type: "BlockStatement" }] },
+        { code: "try { foo() } catch (ex) {}", errors: [{ messageId: "unexpected", data: { type: "block" }, type: "BlockStatement" }] },
+        { code: "try { foo() } catch (ex) {throw ex} finally {}", errors: [{ messageId: "unexpected", data: { type: "block" }, type: "BlockStatement" }] },
+        { code: "if (foo) {}", errors: [{ messageId: "unexpected", data: { type: "block" }, type: "BlockStatement" }] },
+        { code: "while (foo) {}", errors: [{ messageId: "unexpected", data: { type: "block" }, type: "BlockStatement" }] },
+        { code: "for (;foo;) {}", errors: [{ messageId: "unexpected", data: { type: "block" }, type: "BlockStatement" }] },
+        { code: "switch(foo) {}", errors: [{ messageId: "unexpected", data: { type: "switch" }, type: "SwitchStatement" }] },
         {
             code: "try {} catch (ex) {}",
             options: [{ allowEmptyCatch: true }],
-            errors: [{ message: "Empty block statement.", type: "BlockStatement" }]
+            errors: [{ messageId: "unexpected", data: { type: "block" }, type: "BlockStatement" }]
         },
         {
             code: "try { foo(); } catch (ex) {} finally {}",
             options: [{ allowEmptyCatch: true }],
-            errors: [{ message: "Empty block statement.", type: "BlockStatement" }]
+            errors: [{ messageId: "unexpected", data: { type: "block" }, type: "BlockStatement" }]
         },
         {
             code: "try {} catch (ex) {} finally {}",
             options: [{ allowEmptyCatch: true }],
             errors: [
-                { message: "Empty block statement.", type: "BlockStatement" },
-                { message: "Empty block statement.", type: "BlockStatement" }
+                { messageId: "unexpected", data: { type: "block" }, type: "BlockStatement" },
+                { messageId: "unexpected", data: { type: "block" }, type: "BlockStatement" }
             ]
         },
         {
             code: "try { foo(); } catch (ex) {} finally {}",
             errors: [
-                { message: "Empty block statement.", type: "BlockStatement" },
-                { message: "Empty block statement.", type: "BlockStatement" }
+                { messageId: "unexpected", data: { type: "block" }, type: "BlockStatement" },
+                { messageId: "unexpected", data: { type: "block" }, type: "BlockStatement" }
             ]
         }
     ]
diff --git a/tests/lib/rules/no-eq-null.js b/tests/lib/rules/no-eq-null.js
index 23d992dc58f..709913c4230 100644
--- a/tests/lib/rules/no-eq-null.js
+++ b/tests/lib/rules/no-eq-null.js
@@ -18,16 +18,14 @@ const rule = require("../../../lib/rules/no-eq-null"),
 
 const ruleTester = new RuleTester();
 
-const MESSAGE = "Use '===' to compare with null.";
-
 ruleTester.run("no-eq-null", rule, {
     valid: [
         "if (x === null) { }",
         "if (null === f()) { }"
     ],
     invalid: [
-        { code: "if (x == null) { }", errors: [{ message: MESSAGE, type: "BinaryExpression" }] },
-        { code: "if (x != null) { }", errors: [{ message: MESSAGE, type: "BinaryExpression" }] },
-        { code: "do {} while (null == x)", errors: [{ message: MESSAGE, type: "BinaryExpression" }] }
+        { code: "if (x == null) { }", errors: [{ messageId: "unexpected", type: "BinaryExpression" }] },
+        { code: "if (x != null) { }", errors: [{ messageId: "unexpected", type: "BinaryExpression" }] },
+        { code: "do {} while (null == x)", errors: [{ messageId: "unexpected", type: "BinaryExpression" }] }
     ]
 });
diff --git a/tests/lib/rules/no-eval.js b/tests/lib/rules/no-eval.js
index 4ad32137cdf..d31c726b946 100644
--- a/tests/lib/rules/no-eval.js
+++ b/tests/lib/rules/no-eval.js
@@ -63,27 +63,27 @@ ruleTester.run("no-eval", rule, {
     invalid: [
 
         // Direct eval
-        { code: "eval(foo)", errors: [{ message: "eval can be harmful.", type: "CallExpression" }] },
-        { code: "eval('foo')", errors: [{ message: "eval can be harmful.", type: "CallExpression" }] },
-        { code: "function foo(eval) { eval('foo') }", errors: [{ message: "eval can be harmful.", type: "CallExpression" }] },
-        { code: "eval(foo)", options: [{ allowIndirect: true }], errors: [{ message: "eval can be harmful.", type: "CallExpression" }] },
-        { code: "eval('foo')", options: [{ allowIndirect: true }], errors: [{ message: "eval can be harmful.", type: "CallExpression" }] },
-        { code: "function foo(eval) { eval('foo') }", options: [{ allowIndirect: true }], errors: [{ message: "eval can be harmful.", type: "CallExpression" }] },
+        { code: "eval(foo)", errors: [{ messageId: "unexpected", type: "CallExpression" }] },
+        { code: "eval('foo')", errors: [{ messageId: "unexpected", type: "CallExpression" }] },
+        { code: "function foo(eval) { eval('foo') }", errors: [{ messageId: "unexpected", type: "CallExpression" }] },
+        { code: "eval(foo)", options: [{ allowIndirect: true }], errors: [{ messageId: "unexpected", type: "CallExpression" }] },
+        { code: "eval('foo')", options: [{ allowIndirect: true }], errors: [{ messageId: "unexpected", type: "CallExpression" }] },
+        { code: "function foo(eval) { eval('foo') }", options: [{ allowIndirect: true }], errors: [{ messageId: "unexpected", type: "CallExpression" }] },
 
         // Indirect eval
-        { code: "(0, eval)('foo')", errors: [{ message: "eval can be harmful.", type: "Identifier" }] },
-        { code: "(0, window.eval)('foo')", errors: [{ message: "eval can be harmful.", type: "MemberExpression" }], env: { browser: true } },
-        { code: "(0, window['eval'])('foo')", errors: [{ message: "eval can be harmful.", type: "MemberExpression" }], env: { browser: true } },
-        { code: "var EVAL = eval; EVAL('foo')", errors: [{ message: "eval can be harmful.", type: "Identifier" }] },
-        { code: "var EVAL = this.eval; EVAL('foo')", errors: [{ message: "eval can be harmful.", type: "MemberExpression" }] },
-        { code: "(function(exe){ exe('foo') })(eval);", errors: [{ message: "eval can be harmful.", type: "Identifier" }] },
-        { code: "window.eval('foo')", errors: [{ message: "eval can be harmful.", type: "CallExpression" }], env: { browser: true } },
-        { code: "window.window.eval('foo')", errors: [{ message: "eval can be harmful.", type: "CallExpression" }], env: { browser: true } },
-        { code: "window.window['eval']('foo')", errors: [{ message: "eval can be harmful.", type: "CallExpression" }], env: { browser: true } },
-        { code: "global.eval('foo')", errors: [{ message: "eval can be harmful.", type: "CallExpression" }], env: { node: true } },
-        { code: "global.global.eval('foo')", errors: [{ message: "eval can be harmful.", type: "CallExpression" }], env: { node: true } },
-        { code: "global.global[`eval`]('foo')", parserOptions: { ecmaVersion: 6 }, errors: [{ message: "eval can be harmful.", type: "CallExpression" }], env: { node: true } },
-        { code: "this.eval('foo')", errors: [{ message: "eval can be harmful.", type: "CallExpression" }] },
-        { code: "function foo() { this.eval('foo') }", errors: [{ message: "eval can be harmful.", type: "CallExpression" }] }
+        { code: "(0, eval)('foo')", errors: [{ messageId: "unexpected", type: "Identifier" }] },
+        { code: "(0, window.eval)('foo')", errors: [{ messageId: "unexpected", type: "MemberExpression" }], env: { browser: true } },
+        { code: "(0, window['eval'])('foo')", errors: [{ messageId: "unexpected", type: "MemberExpression" }], env: { browser: true } },
+        { code: "var EVAL = eval; EVAL('foo')", errors: [{ messageId: "unexpected", type: "Identifier" }] },
+        { code: "var EVAL = this.eval; EVAL('foo')", errors: [{ messageId: "unexpected", type: "MemberExpression" }] },
+        { code: "(function(exe){ exe('foo') })(eval);", errors: [{ messageId: "unexpected", type: "Identifier" }] },
+        { code: "window.eval('foo')", errors: [{ messageId: "unexpected", type: "CallExpression" }], env: { browser: true } },
+        { code: "window.window.eval('foo')", errors: [{ messageId: "unexpected", type: "CallExpression" }], env: { browser: true } },
+        { code: "window.window['eval']('foo')", errors: [{ messageId: "unexpected", type: "CallExpression" }], env: { browser: true } },
+        { code: "global.eval('foo')", errors: [{ messageId: "unexpected", type: "CallExpression" }], env: { node: true } },
+        { code: "global.global.eval('foo')", errors: [{ messageId: "unexpected", type: "CallExpression" }], env: { node: true } },
+        { code: "global.global[`eval`]('foo')", parserOptions: { ecmaVersion: 6 }, errors: [{ messageId: "unexpected", type: "CallExpression" }], env: { node: true } },
+        { code: "this.eval('foo')", errors: [{ messageId: "unexpected", type: "CallExpression" }] },
+        { code: "function foo() { this.eval('foo') }", errors: [{ messageId: "unexpected", type: "CallExpression" }] }
     ]
 });
diff --git a/tests/lib/rules/no-ex-assign.js b/tests/lib/rules/no-ex-assign.js
index ba753ea9ab7..76ff6fb015d 100644
--- a/tests/lib/rules/no-ex-assign.js
+++ b/tests/lib/rules/no-ex-assign.js
@@ -25,10 +25,10 @@ ruleTester.run("no-ex-assign", rule, {
         "function foo() { try { } catch (e) { return false; } }"
     ],
     invalid: [
-        { code: "try { } catch (e) { e = 10; }", errors: [{ message: "Do not assign to the exception parameter.", type: "Identifier" }] },
-        { code: "try { } catch (ex) { ex = 10; }", errors: [{ message: "Do not assign to the exception parameter.", type: "Identifier" }] },
-        { code: "try { } catch (ex) { [ex] = []; }", parserOptions: { ecmaVersion: 6 }, errors: [{ message: "Do not assign to the exception parameter.", type: "Identifier" }] },
-        { code: "try { } catch (ex) { ({x: ex = 0} = {}); }", parserOptions: { ecmaVersion: 6 }, errors: [{ message: "Do not assign to the exception parameter.", type: "Identifier" }] },
-        { code: "try { } catch ({message}) { message = 10; }", parserOptions: { ecmaVersion: 6 }, errors: [{ message: "Do not assign to the exception parameter.", type: "Identifier" }] }
+        { code: "try { } catch (e) { e = 10; }", errors: [{ messageId: "unexpected", type: "Identifier" }] },
+        { code: "try { } catch (ex) { ex = 10; }", errors: [{ messageId: "unexpected", type: "Identifier" }] },
+        { code: "try { } catch (ex) { [ex] = []; }", parserOptions: { ecmaVersion: 6 }, errors: [{ messageId: "unexpected", type: "Identifier" }] },
+        { code: "try { } catch (ex) { ({x: ex = 0} = {}); }", parserOptions: { ecmaVersion: 6 }, errors: [{ messageId: "unexpected", type: "Identifier" }] },
+        { code: "try { } catch ({message}) { message = 10; }", parserOptions: { ecmaVersion: 6 }, errors: [{ messageId: "unexpected", type: "Identifier" }] }
     ]
 });
diff --git a/tests/lib/rules/no-extend-native.js b/tests/lib/rules/no-extend-native.js
index ec5449a87e3..05923d6b2c4 100644
--- a/tests/lib/rules/no-extend-native.js
+++ b/tests/lib/rules/no-extend-native.js
@@ -52,43 +52,50 @@ ruleTester.run("no-extend-native", rule, {
     invalid: [{
         code: "Object.prototype.p = 0",
         errors: [{
-            message: "Object prototype is read only, properties should not be added.",
+            messageId: "unexpected",
+            data: { builtin: "Object" },
             type: "AssignmentExpression"
         }]
     }, {
         code: "Function.prototype['p'] = 0",
         errors: [{
-            message: "Function prototype is read only, properties should not be added.",
+            messageId: "unexpected",
+            data: { builtin: "Function" },
             type: "AssignmentExpression"
         }]
     }, {
         code: "String['prototype'].p = 0",
         errors: [{
-            message: "String prototype is read only, properties should not be added.",
+            messageId: "unexpected",
+            data: { builtin: "String" },
             type: "AssignmentExpression"
         }]
     }, {
         code: "Number['prototype']['p'] = 0",
         errors: [{
-            message: "Number prototype is read only, properties should not be added.",
+            messageId: "unexpected",
+            data: { builtin: "Number" },
             type: "AssignmentExpression"
         }]
     }, {
         code: "Object.defineProperty(Array.prototype, 'p', {value: 0})",
         errors: [{
-            message: "Array prototype is read only, properties should not be added.",
+            messageId: "unexpected",
+            data: { builtin: "Array" },
             type: "CallExpression"
         }]
     }, {
         code: "Object.defineProperties(Array.prototype, {p: {value: 0}})",
         errors: [{
-            message: "Array prototype is read only, properties should not be added.",
+            messageId: "unexpected",
+            data: { builtin: "Array" },
             type: "CallExpression"
         }]
     }, {
         code: "Object.defineProperties(Array.prototype, {p: {value: 0}, q: {value: 0}})",
         errors: [{
-            message: "Array prototype is read only, properties should not be added.",
+            messageId: "unexpected",
+            data: { builtin: "Array" },
             type: "CallExpression"
         }]
     },
@@ -96,18 +103,21 @@ ruleTester.run("no-extend-native", rule, {
         code: "Number['prototype']['p'] = 0",
         options: [{ exceptions: ["Object"] }],
         errors: [{
-            message: "Number prototype is read only, properties should not be added.",
+            messageId: "unexpected",
+            data: { builtin: "Number" },
             type: "AssignmentExpression"
         }]
     },
     {
         code: "Object.prototype.p = 0; Object.prototype.q = 0",
         errors: [{
-            message: "Object prototype is read only, properties should not be added.",
+            messageId: "unexpected",
+            data: { builtin: "Object" },
             type: "AssignmentExpression",
             column: 1
         }, {
-            message: "Object prototype is read only, properties should not be added.",
+            messageId: "unexpected",
+            data: { builtin: "Object" },
             type: "AssignmentExpression",
             column: 25
         }]
@@ -115,7 +125,8 @@ ruleTester.run("no-extend-native", rule, {
     {
         code: "function foo() { Object.prototype.p = 0 }",
         errors: [{
-            message: "Object prototype is read only, properties should not be added.",
+            messageId: "unexpected",
+            data: { builtin: "Object" },
             type: "AssignmentExpression"
         }]
     }]
diff --git a/tests/lib/rules/no-extra-bind.js b/tests/lib/rules/no-extra-bind.js
index 1aced94560d..4dfec87ac6c 100644
--- a/tests/lib/rules/no-extra-bind.js
+++ b/tests/lib/rules/no-extra-bind.js
@@ -16,7 +16,7 @@ const rule = require("../../../lib/rules/no-extra-bind"),
 //------------------------------------------------------------------------------
 
 const ruleTester = new RuleTester();
-const errors = [{ message: "The function binding is unnecessary.", type: "CallExpression" }];
+const errors = [{ messageId: "unexpected", type: "CallExpression" }];
 
 ruleTester.run("no-extra-bind", rule, {
     valid: [
@@ -73,7 +73,7 @@ ruleTester.run("no-extra-bind", rule, {
         {
             code: "var a = function() { (function(){ (function(){ this.d }.bind(c)) }) }.bind(b)",
             output: "var a = function() { (function(){ (function(){ this.d }.bind(c)) }) }",
-            errors: [{ message: "The function binding is unnecessary.", type: "CallExpression", column: 71 }]
+            errors: [{ messageId: "unexpected", type: "CallExpression", column: 71 }]
         }
     ]
 });
diff --git a/tests/lib/rules/no-extra-boolean-cast.js b/tests/lib/rules/no-extra-boolean-cast.js
index c929167d617..1db0cfb6f7a 100644
--- a/tests/lib/rules/no-extra-boolean-cast.js
+++ b/tests/lib/rules/no-extra-boolean-cast.js
@@ -39,7 +39,7 @@ ruleTester.run("no-extra-boolean-cast", rule, {
             code: "if (!!foo) {}",
             output: "if (foo) {}",
             errors: [{
-                message: "Redundant double negation.",
+                messageId: "unexpectedNegation",
                 type: "UnaryExpression"
             }]
         },
@@ -47,7 +47,7 @@ ruleTester.run("no-extra-boolean-cast", rule, {
             code: "do {} while (!!foo)",
             output: "do {} while (foo)",
             errors: [{
-                message: "Redundant double negation.",
+                messageId: "unexpectedNegation",
                 type: "UnaryExpression"
             }]
         },
@@ -55,7 +55,7 @@ ruleTester.run("no-extra-boolean-cast", rule, {
             code: "while (!!foo) {}",
             output: "while (foo) {}",
             errors: [{
-                message: "Redundant double negation.",
+                messageId: "unexpectedNegation",
                 type: "UnaryExpression"
             }]
         },
@@ -63,7 +63,7 @@ ruleTester.run("no-extra-boolean-cast", rule, {
             code: "!!foo ? bar : baz",
             output: "foo ? bar : baz",
             errors: [{
-                message: "Redundant double negation.",
+                messageId: "unexpectedNegation",
                 type: "UnaryExpression"
             }]
         },
@@ -71,7 +71,7 @@ ruleTester.run("no-extra-boolean-cast", rule, {
             code: "for (; !!foo;) {}",
             output: "for (; foo;) {}",
             errors: [{
-                message: "Redundant double negation.",
+                messageId: "unexpectedNegation",
                 type: "UnaryExpression"
             }]
         },
@@ -79,7 +79,7 @@ ruleTester.run("no-extra-boolean-cast", rule, {
             code: "!!!foo",
             output: "!foo",
             errors: [{
-                message: "Redundant double negation.",
+                messageId: "unexpectedNegation",
                 type: "UnaryExpression"
             }]
         },
@@ -87,7 +87,7 @@ ruleTester.run("no-extra-boolean-cast", rule, {
             code: "Boolean(!!foo)",
             output: "Boolean(foo)",
             errors: [{
-                message: "Redundant double negation.",
+                messageId: "unexpectedNegation",
                 type: "UnaryExpression"
             }]
         },
@@ -95,7 +95,7 @@ ruleTester.run("no-extra-boolean-cast", rule, {
             code: "new Boolean(!!foo)",
             output: "new Boolean(foo)",
             errors: [{
-                message: "Redundant double negation.",
+                messageId: "unexpectedNegation",
                 type: "UnaryExpression"
             }]
         },
@@ -103,7 +103,7 @@ ruleTester.run("no-extra-boolean-cast", rule, {
             code: "if (Boolean(foo)) {}",
             output: "if (foo) {}",
             errors: [{
-                message: "Redundant Boolean call.",
+                messageId: "unexpectedCall",
                 type: "CallExpression"
             }]
         },
@@ -111,7 +111,7 @@ ruleTester.run("no-extra-boolean-cast", rule, {
             code: "do {} while (Boolean(foo))",
             output: "do {} while (foo)",
             errors: [{
-                message: "Redundant Boolean call.",
+                messageId: "unexpectedCall",
                 type: "CallExpression"
             }]
         },
@@ -119,7 +119,7 @@ ruleTester.run("no-extra-boolean-cast", rule, {
             code: "while (Boolean(foo)) {}",
             output: "while (foo) {}",
             errors: [{
-                message: "Redundant Boolean call.",
+                messageId: "unexpectedCall",
                 type: "CallExpression"
             }]
         },
@@ -127,7 +127,7 @@ ruleTester.run("no-extra-boolean-cast", rule, {
             code: "Boolean(foo) ? bar : baz",
             output: "foo ? bar : baz",
             errors: [{
-                message: "Redundant Boolean call.",
+                messageId: "unexpectedCall",
                 type: "CallExpression"
             }]
         },
@@ -135,7 +135,7 @@ ruleTester.run("no-extra-boolean-cast", rule, {
             code: "for (; Boolean(foo);) {}",
             output: "for (; foo;) {}",
             errors: [{
-                message: "Redundant Boolean call.",
+                messageId: "unexpectedCall",
                 type: "CallExpression"
             }]
         },
@@ -143,7 +143,7 @@ ruleTester.run("no-extra-boolean-cast", rule, {
             code: "!Boolean(foo)",
             output: "!foo",
             errors: [{
-                message: "Redundant Boolean call.",
+                messageId: "unexpectedCall",
                 type: "CallExpression"
             }]
         },
@@ -151,7 +151,7 @@ ruleTester.run("no-extra-boolean-cast", rule, {
             code: "!Boolean(foo && bar)",
             output: "!(foo && bar)",
             errors: [{
-                message: "Redundant Boolean call.",
+                messageId: "unexpectedCall",
                 type: "CallExpression"
             }]
         },
@@ -159,7 +159,7 @@ ruleTester.run("no-extra-boolean-cast", rule, {
             code: "!Boolean(foo + bar)",
             output: "!(foo + bar)",
             errors: [{
-                message: "Redundant Boolean call.",
+                messageId: "unexpectedCall",
                 type: "CallExpression"
             }]
         },
@@ -167,7 +167,7 @@ ruleTester.run("no-extra-boolean-cast", rule, {
             code: "!Boolean(+foo)",
             output: "!+foo",
             errors: [{
-                message: "Redundant Boolean call.",
+                messageId: "unexpectedCall",
                 type: "CallExpression"
             }]
         },
@@ -175,7 +175,7 @@ ruleTester.run("no-extra-boolean-cast", rule, {
             code: "!Boolean(foo())",
             output: "!foo()",
             errors: [{
-                message: "Redundant Boolean call.",
+                messageId: "unexpectedCall",
                 type: "CallExpression"
             }]
         },
@@ -183,7 +183,7 @@ ruleTester.run("no-extra-boolean-cast", rule, {
             code: "!Boolean(foo = bar)",
             output: "!(foo = bar)",
             errors: [{
-                message: "Redundant Boolean call.",
+                messageId: "unexpectedCall",
                 type: "CallExpression"
             }]
         },
@@ -192,7 +192,7 @@ ruleTester.run("no-extra-boolean-cast", rule, {
             output: null,
             parserOptions: { ecmaVersion: 2015 },
             errors: [{
-                message: "Redundant Boolean call.",
+                messageId: "unexpectedCall",
                 type: "CallExpression"
             }]
         },
@@ -200,7 +200,7 @@ ruleTester.run("no-extra-boolean-cast", rule, {
             code: "!Boolean(foo, bar());",
             output: null,
             errors: [{
-                message: "Redundant Boolean call.",
+                messageId: "unexpectedCall",
                 type: "CallExpression"
             }]
         },
@@ -208,7 +208,7 @@ ruleTester.run("no-extra-boolean-cast", rule, {
             code: "!Boolean((foo, bar()));",
             output: "!(foo, bar());",
             errors: [{
-                message: "Redundant Boolean call.",
+                messageId: "unexpectedCall",
                 type: "CallExpression"
             }]
         },
@@ -216,7 +216,7 @@ ruleTester.run("no-extra-boolean-cast", rule, {
             code: "!Boolean();",
             output: "true;",
             errors: [{
-                message: "Redundant Boolean call.",
+                messageId: "unexpectedCall",
                 type: "CallExpression"
             }]
         },
@@ -224,7 +224,7 @@ ruleTester.run("no-extra-boolean-cast", rule, {
             code: "!(Boolean());",
             output: "true;",
             errors: [{
-                message: "Redundant Boolean call.",
+                messageId: "unexpectedCall",
                 type: "CallExpression"
             }]
         }
diff --git a/tests/lib/rules/no-extra-label.js b/tests/lib/rules/no-extra-label.js
index 87a28344709..14cc57b9944 100644
--- a/tests/lib/rules/no-extra-label.js
+++ b/tests/lib/rules/no-extra-label.js
@@ -40,53 +40,53 @@ ruleTester.run("no-extra-label", rule, {
         {
             code: "A: while (a) break A;",
             output: "A: while (a) break;",
-            errors: ["This label 'A' is unnecessary."]
+            errors: [{ messageId: "unexpected", data: { name: "A" } }]
         },
         {
             code: "A: while (a) { B: { continue A; } }",
             output: "A: while (a) { B: { continue; } }",
-            errors: ["This label 'A' is unnecessary."]
+            errors: [{ messageId: "unexpected", data: { name: "A" } }]
         },
         {
             code: "X: while (x) { A: while (a) { B: { break A; break B; continue X; } } }",
             output: "X: while (x) { A: while (a) { B: { break; break B; continue X; } } }",
-            errors: ["This label 'A' is unnecessary."]
+            errors: [{ messageId: "unexpected", data: { name: "A" } }]
         },
         {
             code: "A: do { break A; } while (a);",
             output: "A: do { break; } while (a);",
-            errors: ["This label 'A' is unnecessary."]
+            errors: [{ messageId: "unexpected", data: { name: "A" } }]
         },
         {
             code: "A: for (;;) { break A; }",
             output: "A: for (;;) { break; }",
-            errors: ["This label 'A' is unnecessary."]
+            errors: [{ messageId: "unexpected", data: { name: "A" } }]
         },
         {
             code: "A: for (a in obj) { break A; }",
             output: "A: for (a in obj) { break; }",
-            errors: ["This label 'A' is unnecessary."]
+            errors: [{ messageId: "unexpected", data: { name: "A" } }]
         },
         {
             code: "A: for (a of ary) { break A; }",
             output: "A: for (a of ary) { break; }",
             parserOptions: { ecmaVersion: 6 },
-            errors: ["This label 'A' is unnecessary."]
+            errors: [{ messageId: "unexpected", data: { name: "A" } }]
         },
         {
             code: "A: switch (a) { case 0: break A; }",
             output: "A: switch (a) { case 0: break; }",
-            errors: ["This label 'A' is unnecessary."]
+            errors: [{ messageId: "unexpected", data: { name: "A" } }]
         },
         {
             code: "X: while (x) { A: switch (a) { case 0: break A; } }",
             output: "X: while (x) { A: switch (a) { case 0: break; } }",
-            errors: ["This label 'A' is unnecessary."]
+            errors: [{ messageId: "unexpected", data: { name: "A" } }]
         },
         {
             code: "X: switch (a) { case 0: A: while (b) break A; }",
             output: "X: switch (a) { case 0: A: while (b) break; }",
-            errors: ["This label 'A' is unnecessary."]
+            errors: [{ messageId: "unexpected", data: { name: "A" } }]
         },
         {
             code: `\
@@ -105,7 +105,7 @@ ruleTester.run("no-extra-label", rule, {
                     }
                 }
             `,
-            errors: [{ message: "This label 'A' is unnecessary.", type: "Identifier", line: 2 }]
+            errors: [{ messageId: "unexpected", data: { name: "A" }, type: "Identifier", line: 2 }]
         }
     ]
 });
diff --git a/tests/lib/rules/no-extra-parens.js b/tests/lib/rules/no-extra-parens.js
index cab241a0a3e..3df00d516b4 100644
--- a/tests/lib/rules/no-extra-parens.js
+++ b/tests/lib/rules/no-extra-parens.js
@@ -31,7 +31,7 @@ function invalid(code, output, type, line, config) {
         parserOptions: config.parserOptions || {},
         errors: [
             {
-                message: "Gratuitous parentheses around expression.",
+                messageId: "unexpected",
                 type
             }
         ],
@@ -709,7 +709,7 @@ ruleTester.run("no-extra-parens", rule, {
             options: ["all", { returnAssign: false }],
             errors: [
                 {
-                    message: "Gratuitous parentheses around expression.",
+                    messgeId: "unexpected",
                     type: "LogicalExpression"
                 }
             ]
@@ -719,7 +719,7 @@ ruleTester.run("no-extra-parens", rule, {
             output: "function a(b) { return (b = c) || (d = e); }",
             errors: [
                 {
-                    message: "Gratuitous parentheses around expression.",
+                    messgeId: "unexpected",
                     type: "LogicalExpression"
                 }
             ]
@@ -729,7 +729,7 @@ ruleTester.run("no-extra-parens", rule, {
             output: "function a(b) { return b = 1; }",
             errors: [
                 {
-                    message: "Gratuitous parentheses around expression.",
+                    messgeId: "unexpected",
                     type: "AssignmentExpression"
                 }
             ]
@@ -739,11 +739,11 @@ ruleTester.run("no-extra-parens", rule, {
             output: "function a(b) { return c ? d = b : e = b; }",
             errors: [
                 {
-                    message: "Gratuitous parentheses around expression.",
+                    messgeId: "unexpected",
                     type: "AssignmentExpression"
                 },
                 {
-                    message: "Gratuitous parentheses around expression.",
+                    messgeId: "unexpected",
                     type: "AssignmentExpression"
                 }
             ]
@@ -755,7 +755,7 @@ ruleTester.run("no-extra-parens", rule, {
 
             errors: [
                 {
-                    message: "Gratuitous parentheses around expression.",
+                    messgeId: "unexpected",
                     type: "LogicalExpression"
                 }
             ]
@@ -765,7 +765,7 @@ ruleTester.run("no-extra-parens", rule, {
             output: "b => (b = c) || (d = e);",
             errors: [
                 {
-                    message: "Gratuitous parentheses around expression.",
+                    messgeId: "unexpected",
                     type: "LogicalExpression"
                 }
             ]
@@ -775,7 +775,7 @@ ruleTester.run("no-extra-parens", rule, {
             output: "b => b = 1;",
             errors: [
                 {
-                    message: "Gratuitous parentheses around expression.",
+                    messgeId: "unexpected",
                     type: "AssignmentExpression"
                 }
             ]
@@ -785,11 +785,11 @@ ruleTester.run("no-extra-parens", rule, {
             output: "b => c ? d = b : e = b;",
             errors: [
                 {
-                    message: "Gratuitous parentheses around expression.",
+                    messgeId: "unexpected",
                     type: "AssignmentExpression"
                 },
                 {
-                    message: "Gratuitous parentheses around expression.",
+                    messgeId: "unexpected",
                     type: "AssignmentExpression"
                 }
             ]
@@ -800,7 +800,7 @@ ruleTester.run("no-extra-parens", rule, {
             options: ["all", { returnAssign: false }],
             errors: [
                 {
-                    message: "Gratuitous parentheses around expression.",
+                    messgeId: "unexpected",
                     type: "LogicalExpression"
                 }
             ]
@@ -810,7 +810,7 @@ ruleTester.run("no-extra-parens", rule, {
             output: "b => { return (b = c) || (d = e) };",
             errors: [
                 {
-                    message: "Gratuitous parentheses around expression.",
+                    messgeId: "unexpected",
                     type: "LogicalExpression"
                 }
             ]
@@ -820,7 +820,7 @@ ruleTester.run("no-extra-parens", rule, {
             output: "b => { return b = 1 };",
             errors: [
                 {
-                    message: "Gratuitous parentheses around expression.",
+                    messgeId: "unexpected",
                     type: "AssignmentExpression"
                 }
             ]
@@ -830,11 +830,11 @@ ruleTester.run("no-extra-parens", rule, {
             output: "b => { return c ? d = b : e = b; }",
             errors: [
                 {
-                    message: "Gratuitous parentheses around expression.",
+                    messgeId: "unexpected",
                     type: "AssignmentExpression"
                 },
                 {
-                    message: "Gratuitous parentheses around expression.",
+                    messgeId: "unexpected",
                     type: "AssignmentExpression"
                 }
             ]
@@ -846,11 +846,11 @@ ruleTester.run("no-extra-parens", rule, {
             output: "async function a() { await a + await b; }",
             errors: [
                 {
-                    message: "Gratuitous parentheses around expression.",
+                    messgeId: "unexpected",
                     type: "AwaitExpression"
                 },
                 {
-                    message: "Gratuitous parentheses around expression.",
+                    messgeId: "unexpected",
                     type: "AwaitExpression"
                 }
             ]
@@ -924,7 +924,7 @@ ruleTester.run("no-extra-parens", rule, {
             options: ["all", { enforceForArrowConditionals: true }],
             errors: [
                 {
-                    message: "Gratuitous parentheses around expression."
+                    messgeId: "unexpected"
                 }
             ]
         },
@@ -936,7 +936,7 @@ ruleTester.run("no-extra-parens", rule, {
             options: ["all", { enforceForArrowConditionals: false }],
             errors: [
                 {
-                    message: "Gratuitous parentheses around expression."
+                    messgeId: "unexpected"
                 }
             ]
         },
diff --git a/tests/lib/rules/no-extra-semi.js b/tests/lib/rules/no-extra-semi.js
index 036cb1f4b2c..dc465253448 100644
--- a/tests/lib/rules/no-extra-semi.js
+++ b/tests/lib/rules/no-extra-semi.js
@@ -47,68 +47,68 @@ ruleTester.run("no-extra-semi", rule, {
         {
             code: "var x = 5;;",
             output: "var x = 5;",
-            errors: [{ message: "Unnecessary semicolon.", type: "EmptyStatement" }]
+            errors: [{ messgeId: "unexpected", type: "EmptyStatement" }]
         },
         {
             code: "function foo(){};",
             output: "function foo(){}",
-            errors: [{ message: "Unnecessary semicolon.", type: "EmptyStatement" }]
+            errors: [{ messgeId: "unexpected", type: "EmptyStatement" }]
         },
         {
             code: "for(;;);;",
             output: "for(;;);",
-            errors: [{ message: "Unnecessary semicolon.", type: "EmptyStatement" }]
+            errors: [{ messgeId: "unexpected", type: "EmptyStatement" }]
         },
         {
             code: "while(0);;",
             output: "while(0);",
-            errors: [{ message: "Unnecessary semicolon.", type: "EmptyStatement" }]
+            errors: [{ messgeId: "unexpected", type: "EmptyStatement" }]
         },
         {
             code: "do;while(0);;",
             output: "do;while(0);",
-            errors: [{ message: "Unnecessary semicolon.", type: "EmptyStatement" }]
+            errors: [{ messgeId: "unexpected", type: "EmptyStatement" }]
         },
         {
             code: "for(a in b);;",
             output: "for(a in b);",
-            errors: [{ message: "Unnecessary semicolon.", type: "EmptyStatement" }]
+            errors: [{ messgeId: "unexpected", type: "EmptyStatement" }]
         },
         {
             code: "for(a of b);;",
             output: "for(a of b);",
             parserOptions: { ecmaVersion: 6 },
-            errors: [{ message: "Unnecessary semicolon.", type: "EmptyStatement" }]
+            errors: [{ messgeId: "unexpected", type: "EmptyStatement" }]
         },
         {
             code: "if(true);;",
             output: "if(true);",
-            errors: [{ message: "Unnecessary semicolon.", type: "EmptyStatement" }]
+            errors: [{ messgeId: "unexpected", type: "EmptyStatement" }]
         },
         {
             code: "if(true){} else;;",
             output: "if(true){} else;",
-            errors: [{ message: "Unnecessary semicolon.", type: "EmptyStatement" }]
+            errors: [{ messgeId: "unexpected", type: "EmptyStatement" }]
         },
         {
             code: "if(true){;} else {;}",
             output: "if(true){} else {}",
-            errors: [{ message: "Unnecessary semicolon.", type: "EmptyStatement" }, { message: "Unnecessary semicolon.", type: "EmptyStatement" }]
+            errors: [{ messgeId: "unexpected", type: "EmptyStatement" }, { messgeId: "unexpected", type: "EmptyStatement" }]
         },
         {
             code: "foo:;;",
             output: "foo:;",
-            errors: [{ message: "Unnecessary semicolon.", type: "EmptyStatement" }]
+            errors: [{ messgeId: "unexpected", type: "EmptyStatement" }]
         },
         {
             code: "with(foo);;",
             output: "with(foo);",
-            errors: [{ message: "Unnecessary semicolon.", type: "EmptyStatement" }]
+            errors: [{ messgeId: "unexpected", type: "EmptyStatement" }]
         },
         {
             code: "with(foo){;}",
             output: "with(foo){}",
-            errors: [{ message: "Unnecessary semicolon.", type: "EmptyStatement" }]
+            errors: [{ messgeId: "unexpected", type: "EmptyStatement" }]
         },
 
         // Class body.
@@ -116,47 +116,47 @@ ruleTester.run("no-extra-semi", rule, {
             code: "class A { ; }",
             output: "class A {  }",
             parserOptions: { ecmaVersion: 6 },
-            errors: [{ message: "Unnecessary semicolon.", type: "Punctuator", column: 11 }]
+            errors: [{ messgeId: "unexpected", type: "Punctuator", column: 11 }]
         },
         {
             code: "class A { /*a*/; }",
             output: "class A { /*a*/ }",
             parserOptions: { ecmaVersion: 6 },
-            errors: [{ message: "Unnecessary semicolon.", type: "Punctuator", column: 16 }]
+            errors: [{ messgeId: "unexpected", type: "Punctuator", column: 16 }]
         },
         {
             code: "class A { ; a() {} }",
             output: "class A {  a() {} }",
             parserOptions: { ecmaVersion: 6 },
-            errors: [{ message: "Unnecessary semicolon.", type: "Punctuator", column: 11 }]
+            errors: [{ messgeId: "unexpected", type: "Punctuator", column: 11 }]
         },
         {
             code: "class A { a() {}; }",
             output: "class A { a() {} }",
             parserOptions: { ecmaVersion: 6 },
-            errors: [{ message: "Unnecessary semicolon.", type: "Punctuator", column: 17 }]
+            errors: [{ messgeId: "unexpected", type: "Punctuator", column: 17 }]
         },
         {
             code: "class A { a() {}; b() {} }",
             output: "class A { a() {} b() {} }",
             parserOptions: { ecmaVersion: 6 },
-            errors: [{ message: "Unnecessary semicolon.", type: "Punctuator", column: 17 }]
+            errors: [{ messgeId: "unexpected", type: "Punctuator", column: 17 }]
         },
         {
             code: "class A {; a() {}; b() {}; }",
             output: "class A { a() {} b() {} }",
             parserOptions: { ecmaVersion: 6 },
             errors: [
-                { message: "Unnecessary semicolon.", type: "Punctuator", column: 10 },
-                { message: "Unnecessary semicolon.", type: "Punctuator", column: 18 },
-                { message: "Unnecessary semicolon.", type: "Punctuator", column: 26 }
+                { messgeId: "unexpected", type: "Punctuator", column: 10 },
+                { messgeId: "unexpected", type: "Punctuator", column: 18 },
+                { messgeId: "unexpected", type: "Punctuator", column: 26 }
             ]
         },
         {
             code: "class A { a() {}; get b() {} }",
             output: "class A { a() {} get b() {} }",
             parserOptions: { ecmaVersion: 6 },
-            errors: [{ message: "Unnecessary semicolon.", type: "Punctuator", column: 17 }]
+            errors: [{ messgeId: "unexpected", type: "Punctuator", column: 17 }]
         }
     ]
 });