feat: add restrictDefaultExports option to no-restricted-exports rule

docs/src/rules/no-restricted-exports.md

@@ -17,8 +17,16 @@ By default, this rule doesn't disallow any names. Only the names you specify in
 This rule has an object option:
 
 * `"restrictedNamedExports"` is an array of strings, where each string is a name to be restricted.
+* `"restrictDefaultExports"` is an object option with boolean properties to restrict certain default export declarations. The option works only if the `restrictedNamedExports` option does not contain the `"default"` value. The following properties are allowed:
+    * `direct`: restricts `export default` declarations.
+    * `named`: restricts `export { foo as default };` declarations.
+    * `defaultFrom`: restricts `export { default } from 'foo';` declarations.
+    * `namedFrom`: restricts `export { foo as default } from 'foo';` declarations.
+    * `namespaceFrom`: restricts `export * as default from 'foo';` declarations.
 
-Examples of **incorrect** code for this rule:
+### restrictedNamedExports
+
+Examples of **incorrect** code for the `"restrictedNamedExports"` option:
 
 ::: incorrect
 
@@ -50,7 +58,7 @@ export { "👍" } from "some_module";
 
 :::
 
-Examples of **correct** code for this rule:
+Examples of **correct** code for the `"restrictedNamedExports"` option:
 
 ::: correct
 
@@ -82,11 +90,11 @@ export { "👍" as thumbsUp } from "some_module";
 
 :::
 
-### Default exports
+#### Default exports
 
-By design, this rule doesn't disallow `export default` declarations. If you configure `"default"` as a restricted name, that restriction will apply only to named export declarations.
+By design, the `"restrictedNamedExports"` option doesn't disallow `export default` declarations. If you configure `"default"` as a restricted name, that restriction will apply only to named export declarations.
 
-Examples of additional **incorrect** code for this rule:
+Examples of additional **incorrect** code for the `"restrictedNamedExports": ["default"]` option:
 
 ::: incorrect
 
@@ -110,7 +118,7 @@ export { default } from "some_module";
 
 :::
 
-Examples of additional **correct** code for this rule:
+Examples of additional **correct** code for the `"restrictedNamedExports": ["default"]` option:
 
 ::: correct
 
@@ -122,6 +130,85 @@ export default function foo() {}
 
 :::
 
+### restrictDefaultExports
+
+This option allows you to restrict certain `default` declarations. The option works only if the `restrictedNamedExports` option does not contain the `"default"` value. This option accepts the following properties:
+
+#### direct
+
+Examples of **incorrect** code for the `"restrictDefaultExports": { "direct": true }` option:
+
+::: incorrect
+
+```js
+/*eslint no-restricted-exports: ["error", { "restrictDefaultExports": { "direct": true } }]*/
+
+export default foo;
+export default 42;
+export default function foo() {};
+```
+
+:::
+
+#### named
+
+Examples of **incorrect** code for the `"restrictDefaultExports": { "named": true }` option:
+
+::: incorrect
+
+```js
+/*eslint no-restricted-exports: ["error", { "restrictDefaultExports": { "named": true } }]*/
+
+const foo = 123;
+
+export { foo as default };
+```
+
+:::
+
+#### defaultFrom
+
+Examples of **incorrect** code for the `"restrictDefaultExports": { "defaultFrom": true }` option:
+
+::: incorrect
+
+```js
+/*eslint no-restricted-exports: ["error", { "restrictDefaultExports": { "defaultFrom": true } }]*/
+
+export { default } from 'foo';
+export { default as default } from 'foo';
+```
+
+:::
+
+#### namedFrom
+
+Examples of **incorrect** code for the `"restrictDefaultExports": { "namedFrom": true }` option:
+
+::: incorrect
+
+```js
+/*eslint no-restricted-exports: ["error", { "restrictDefaultExports": { "namedFrom": true } }]*/
+
+export { foo as default } from 'foo';
+```
+
+:::
+
+#### namespaceFrom
+
+Examples of **incorrect** code for the `"restrictDefaultExports": { "namespaceFrom": true }` option:
+
+::: incorrect
+
+```js
+/*eslint no-restricted-exports: ["error", { "restrictDefaultExports": { "namespaceFrom": true } }]*/
+
+export * as default from 'foo';
+```
+
+:::
+
 ## Known Limitations
 
 This rule doesn't inspect the content of source modules in re-export declarations. In particular, if you are re-exporting everything from another module's export, that export may include a restricted name. This rule cannot detect such cases.

lib/rules/no-restricted-exports.js

@@ -27,27 +27,78 @@ module.exports = {
         },
 
         schema: [{
-            type: "object",
-            properties: {
-                restrictedNamedExports: {
-                    type: "array",
-                    items: {
-                        type: "string"
+            anyOf: [
+                {
+                    type: "object",
+                    properties: {
+                        restrictedNamedExports: {
+                            type: "array",
+                            items: {
+                                type: "string"
+                            },
+                            uniqueItems: true
+                        }
                     },
-                    uniqueItems: true
+                    additionalProperties: false
+                },
+                {
+                    type: "object",
+                    properties: {
+                        restrictedNamedExports: {
+                            type: "array",
+                            items: {
+                                type: "string",
+                                pattern: "^(?!default$)"
+                            },
+                            uniqueItems: true
+                        },
+                        restrictDefaultExports: {
+                            type: "object",
+                            properties: {
+
+                                // Allow/Disallow `export default foo; export default 42; export default function foo() {}` format
+                                direct: {
+                                    type: "boolean"
+                                },
+
+                                // Allow/Disallow `export { foo as default };` declarations
+                                named: {
+                                    type: "boolean"
+                                },
+
+                                //  Allow/Disallow `export { default } from "mod"; export { default as default } from "mod";` declarations
+                                defaultFrom: {
+                                    type: "boolean"
+                                },
+
+                                //  Allow/Disallow `export { foo as default } from "mod";` declarations
+                                namedFrom: {
+                                    type: "boolean"
+                                },
+
+                                //  Allow/Disallow `export * as default from "mod"`; declarations
+                                namespaceFrom: {
+                                    type: "boolean"
+                                }
+                            },
+                            additionalProperties: false
+                        }
+                    },
+                    additionalProperties: false
                 }
-            },
-            additionalProperties: false
+            ]
         }],
 
         messages: {
-            restrictedNamed: "'{{name}}' is restricted from being used as an exported name."
+            restrictedNamed: "'{{name}}' is restricted from being used as an exported name.",
+            restrictedDefault: "Exporting the 'default' value is restricted."
         }
     },
 
     create(context) {
 
         const restrictedNames = new Set(context.options[0] && context.options[0].restrictedNamedExports);
+        const restrictDefaultExports = context.options[0] && context.options[0].restrictDefaultExports;
 
         /**
          * Checks and reports given exported name.
@@ -63,6 +114,42 @@ module.exports = {
                     messageId: "restrictedNamed",
                     data: { name }
                 });
+                return;
+            }
+
+            if (name === "default") {
+                if (node.parent.type === "ExportAllDeclaration") {
+                    if (restrictDefaultExports && restrictDefaultExports.namespaceFrom) {
+                        context.report({
+                            node,
+                            messageId: "restrictedDefault"
+                        });
+                    }
+
+                } else { // ExportSpecifier
+                    const isSourceSpecified = !!node.parent.parent.source;
+                    const specifierLocalName = astUtils.getModuleExportName(node.parent.local);
+
+                    if (!isSourceSpecified && restrictDefaultExports && restrictDefaultExports.named) {
+                        context.report({
+                            node,
+                            messageId: "restrictedDefault"
+                        });
+                        return;
+                    }
+
+                    if (isSourceSpecified && restrictDefaultExports) {
+                        if (
+                            (specifierLocalName === "default" && restrictDefaultExports.defaultFrom) ||
+                            (specifierLocalName !== "default" && restrictDefaultExports.namedFrom)
+                        ) {
+                            context.report({
+                                node,
+                                messageId: "restrictedDefault"
+                            });
+                        }
+                    }
+                }
             }
         }
 
@@ -73,6 +160,15 @@ module.exports = {
                 }
             },
 
+            ExportDefaultDeclaration(node) {
+                if (restrictDefaultExports && restrictDefaultExports.direct) {
+                    context.report({
+                        node,
+                        messageId: "restrictedDefault"
+                    });
+                }
+            },
+
             ExportNamedDeclaration(node) {
                 const declaration = node.declaration;
 

tests/lib/rules/no-restricted-exports.js

@@ -107,7 +107,31 @@ ruleTester.run("no-restricted-exports", rule, {
         { code: "export default 1;", options: [{ restrictedNamedExports: ["default"] }] },
 
         // "default" does not disallow re-exporting a renamed default export from another module
-        { code: "export { default as a } from 'foo';", options: [{ restrictedNamedExports: ["default"] }] }
+        { code: "export { default as a } from 'foo';", options: [{ restrictedNamedExports: ["default"] }] },
+
+        // restrictDefaultExports.direct option
+        { code: "export default foo;", options: [{ restrictDefaultExports: { direct: false } }] },
+        { code: "export default 42;", options: [{ restrictDefaultExports: { direct: false } }] },
+        { code: "export default function foo() {}", options: [{ restrictDefaultExports: { direct: false } }] },
+
+        // restrictDefaultExports.named option
+        { code: "const foo = 123;\nexport { foo as default };", options: [{ restrictDefaultExports: { named: false } }] },
+
+        // restrictDefaultExports.defaultFrom option
+        { code: "export { default } from 'mod';", options: [{ restrictDefaultExports: { defaultFrom: false } }] },
+        { code: "export { default as default } from 'mod';", options: [{ restrictDefaultExports: { defaultFrom: false } }] },
+        { code: "export { foo as default } from 'mod';", options: [{ restrictDefaultExports: { defaultFrom: true } }] },
+        { code: "export { default } from 'mod';", options: [{ restrictDefaultExports: { named: true, defaultFrom: false } }] },
+        { code: "export { 'default' } from 'mod'; ", options: [{ restrictDefaultExports: { defaultFrom: false } }] },
+
+        // restrictDefaultExports.namedFrom option
+        { code: "export { foo as default } from 'mod';", options: [{ restrictDefaultExports: { namedFrom: false } }] },
+        { code: "export { default as default } from 'mod';", options: [{ restrictDefaultExports: { namedFrom: true } }] },
+        { code: "export { default as default } from 'mod';", options: [{ restrictDefaultExports: { namedFrom: false } }] },
+        { code: "export { 'default' } from 'mod'; ", options: [{ restrictDefaultExports: { defaultFrom: false, namedFrom: true } }] },
+
+        // restrictDefaultExports.namespaceFrom option
+        { code: "export * as default from 'mod';", options: [{ restrictDefaultExports: { namespaceFrom: false } }] }
     ],
 
     invalid: [
@@ -519,6 +543,66 @@ ruleTester.run("no-restricted-exports", rule, {
             code: "export { default } from 'foo';",
             options: [{ restrictedNamedExports: ["default"] }],
             errors: [{ messageId: "restrictedNamed", data: { name: "default" }, type: "Identifier", column: 10 }]
+        },
+
+        // restrictDefaultExports.direct option
+        {
+            code: "export default foo;",
+            options: [{ restrictDefaultExports: { direct: true } }],
+            errors: [{ messageId: "restrictedDefault", type: "ExportDefaultDeclaration", column: 1 }]
+        },
+        {
+            code: "export default 42;",
+            options: [{ restrictDefaultExports: { direct: true } }],
+            errors: [{ messageId: "restrictedDefault", type: "ExportDefaultDeclaration", column: 1 }]
+        },
+        {
+            code: "export default function foo() {};",
+            options: [{ restrictDefaultExports: { direct: true } }],
+            errors: [{ messageId: "restrictedDefault", type: "ExportDefaultDeclaration", column: 1 }]
+        },
+        {
+            code: "export default foo;",
+            options: [{ restrictedNamedExports: ["bar"], restrictDefaultExports: { direct: true } }],
+            errors: [{ messageId: "restrictedDefault", type: "ExportDefaultDeclaration", column: 1 }]
+        },
+
+        // restrictDefaultExports.named option
+        {
+            code: "const foo = 123;\nexport { foo as default };",
+            options: [{ restrictDefaultExports: { named: true } }],
+            errors: [{ messageId: "restrictedDefault", type: "Identifier", line: 2, column: 17 }]
+        },
+
+        // restrictDefaultExports.defaultFrom option
+        {
+            code: "export { default } from 'mod';",
+            options: [{ restrictDefaultExports: { defaultFrom: true } }],
+            errors: [{ messageId: "restrictedDefault", type: "Identifier", line: 1, column: 10 }]
+        },
+        {
+            code: "export { default as default } from 'mod';",
+            options: [{ restrictDefaultExports: { defaultFrom: true } }],
+            errors: [{ messageId: "restrictedDefault", type: "Identifier", line: 1, column: 21 }]
+        },
+        {
+            code: "export { 'default' } from 'mod';",
+            options: [{ restrictDefaultExports: { defaultFrom: true } }],
+            errors: [{ messageId: "restrictedDefault", type: "Literal", line: 1, column: 10 }]
+        },
+
+        // restrictDefaultExports.namedFrom option
+        {
+            code: "export { foo as default } from 'mod';",
+            options: [{ restrictDefaultExports: { namedFrom: true } }],
+            errors: [{ messageId: "restrictedDefault", type: "Identifier", line: 1, column: 17 }]
+        },
+
+        // restrictDefaultExports.namespaceFrom option
+        {
+            code: "export * as default from 'mod';",
+            options: [{ restrictDefaultExports: { namespaceFrom: true } }],
+            errors: [{ messageId: "restrictedDefault", type: "Identifier", line: 1, column: 13 }]
         }
     ]
 });