chore: precompile with babel

.eslintignore

@@ -1 +1,2 @@
 coverage/
+lib/

.eslintrc.js

@@ -1,6 +1,6 @@
 'use strict';
 
-const { globals } = require('./index').environments.globals;
+const { globals } = require('./').environments.globals;
 
 module.exports = {
   extends: [
@@ -32,6 +32,8 @@ module.exports = {
       },
     ],
     'prettier/prettier': 'error',
+    'node/no-unsupported-features/es-syntax': 'off',
+    'node/no-unsupported-features/es-builtins': 'error',
   },
   overrides: [
     {

.gitignore

@@ -1,2 +1,3 @@
 node_modules/
 coverage/
+lib/

babel.config.js

@@ -0,0 +1,5 @@
+'use strict';
+
+module.exports = {
+  presets: [['@babel/preset-env', { targets: { node: 6 } }]],
+};

package.json

@@ -16,24 +16,31 @@
   },
   "files": [
     "docs/",
-    "rules/",
-    "processors/",
-    "index.js"
+    "src/",
+    "lib/"
   ],
+  "main": "lib/",
   "engines": {
     "node": ">=6"
   },
   "peerDependencies": {
     "eslint": ">=5"
   },
   "scripts": {
+    "postinstall": "yarn build",
     "lint": "eslint . --ignore-pattern '!.eslintrc.js'",
     "prettylint": "prettylint docs/**/*.md README.md package.json",
-    "test": "jest"
+    "prepublishOnly": "yarn build",
+    "test": "jest",
+    "build": "babel src --out-dir lib"
   },
   "devDependencies": {
+    "@babel/cli": "^7.4.4",
+    "@babel/core": "^7.4.4",
+    "@babel/preset-env": "^7.4.4",
     "@commitlint/cli": "^7.0.0",
     "@commitlint/config-conventional": "^7.0.1",
+    "babel-jest": "^24.8.0",
     "eslint": "^5.1.0",
     "eslint-config-prettier": "^4.1.0",
     "eslint-plugin-eslint-plugin": "^2.0.0",
@@ -49,7 +56,7 @@
   "prettier": {
     "proseWrap": "always",
     "singleQuote": true,
-    "trailingComma": "es5"
+    "trailingComma": "all"
   },
   "lint-staged": {
     "*.js": [
@@ -73,13 +80,19 @@
     "projects": [
       {
         "displayName": "test",
-        "testEnvironment": "node"
+        "testEnvironment": "node",
+        "testPathIgnorePatterns": [
+          "<rootDir>/lib/.*"
+        ]
       },
       {
         "displayName": "lint",
         "runner": "jest-runner-eslint",
         "testMatch": [
           "<rootDir>/**/*.js"
+        ],
+        "testPathIgnorePatterns": [
+          "<rootDir>/lib/.*"
         ]
       }
     ]

__tests__/rules.test.js → src/__tests__/rules.test.js

@@ -2,19 +2,19 @@
 
 const fs = require('fs');
 const path = require('path');
-const { rules } = require('../index');
+const { rules } = require('../');
 
 const ruleNames = Object.keys(rules);
 const numberOfRules = 31;
 
 describe('rules', () => {
   it('should have a corresponding doc for each rule', () => {
     ruleNames.forEach(rule => {
-      const docPath = path.resolve(__dirname, '../docs/rules', `${rule}.md`);
+      const docPath = path.resolve(__dirname, '../../docs/rules', `${rule}.md`);
 
       if (!fs.existsSync(docPath)) {
         throw new Error(
-          `Could not find documentation file for rule "${rule}" in path "${docPath}"`
+          `Could not find documentation file for rule "${rule}" in path "${docPath}"`,
         );
       }
     });
@@ -24,7 +24,7 @@ describe('rules', () => {
     const { length } = ruleNames;
     if (length !== numberOfRules) {
       throw new Error(
-        `There should be exactly ${numberOfRules} rules, but there are ${length}. If you've added a new rule, please update this number.`
+        `There should be exactly ${numberOfRules} rules, but there are ${length}. If you've added a new rule, please update this number.`,
       );
     }
   });

index.js → src/index.js

@@ -9,7 +9,7 @@ const rules = fs
   .map(rule => path.basename(rule, '.js'))
   .reduce(
     (acc, curr) => Object.assign(acc, { [curr]: require(`./rules/${curr}`) }),
-    {}
+    {},
   );
 
 const snapshotProcessor = require('./processors/snapshot-processor');

processors/snapshot-processor.js → src/processors/snapshot-processor.js

@@ -6,7 +6,7 @@ const preprocess = source => [source];
 const postprocess = messages =>
   messages[0].filter(
     // snapshot files should only be linted with snapshot specific rules
-    message => message.ruleId === 'jest/no-large-snapshots'
+    message => message.ruleId === 'jest/no-large-snapshots',
   );
 
 module.exports = {

rules/__tests__/consistent-test-it.test.js → src/rules/__tests__/consistent-test-it.test.js

@@ -285,7 +285,7 @@ ruleTester.run(
         output: 'test("foo")',
       },
     ],
-  }
+  },
 );
 
 ruleTester.run('consistent-test-it with fn=it and withinDescribe=it ', rule, {

rules/__tests__/no-identical-title.test.js → src/rules/__tests__/no-identical-title.test.js

@@ -23,10 +23,10 @@ ruleTester.run('no-identical-title', rule, {
     ['it("it1", function() {});', 'it("it2", function() {});'].join('\n'),
     ['it.only("it1", function() {});', 'it("it2", function() {});'].join('\n'),
     ['it.only("it1", function() {});', 'it.only("it2", function() {});'].join(
-      '\n'
+      '\n',
     ),
     ['describe("title", function() {});', 'it("title", function() {});'].join(
-      '\n'
+      '\n',
     ),
     [
       'describe("describe1", function() {',
@@ -136,7 +136,7 @@ ruleTester.run('no-identical-title', rule, {
     },
     {
       code: ['it("it1", function() {});', 'it("it1", function() {});'].join(
-        '\n'
+        '\n',
       ),
       errors: [
         {
@@ -163,7 +163,7 @@ ruleTester.run('no-identical-title', rule, {
     },
     {
       code: ['fit("it1", function() {});', 'it("it1", function() {});'].join(
-        '\n'
+        '\n',
       ),
       errors: [
         {

rules/__tests__/no-large-snapshots.test.js → src/rules/__tests__/no-large-snapshots.test.js

@@ -15,21 +15,21 @@ ruleTester.run('no-large-snapshots', rule, {
     {
       filename: 'mock.js',
       code: `expect(something).toMatchInlineSnapshot(\`\n${'line\n'.repeat(
-        2
+        2,
       )}\`);`,
     },
     {
       filename: 'mock.js',
       code: `expect(something).toThrowErrorMatchingInlineSnapshot(\`\n${'line\n'.repeat(
-        2
+        2,
       )}\`);`,
     },
   ],
   invalid: [
     {
       filename: 'mock.js',
       code: `expect(something).toMatchInlineSnapshot(\`\n${'line\n'.repeat(
-        50
+        50,
       )}\`);`,
       errors: [
         {
@@ -41,7 +41,7 @@ ruleTester.run('no-large-snapshots', rule, {
     {
       filename: 'mock.js',
       code: `expect(something).toThrowErrorMatchingInlineSnapshot(\`\n${'line\n'.repeat(
-        50
+        50,
       )}\`);`,
       errors: [
         {

rules/consistent-test-it.js → src/rules/consistent-test-it.js

@@ -69,7 +69,7 @@ module.exports = {
           nodeName.indexOf(testKeywordWithinDescribe) === -1
         ) {
           const oppositeTestKeyword = getOppositeTestKeyword(
-            testKeywordWithinDescribe
+            testKeywordWithinDescribe,
           );
 
           context.report({
@@ -85,7 +85,7 @@ module.exports = {
 
               const fixedNodeName = getPreferredNodeName(
                 nodeName,
-                testKeywordWithinDescribe
+                testKeywordWithinDescribe,
               );
               return [fixer.replaceText(nodeToReplace, fixedNodeName)];
             },

rules/expect-expect.js → src/rules/expect-expect.js

@@ -30,7 +30,7 @@ module.exports = {
     const assertFunctionNames = new Set(
       context.options[0] && context.options[0].assertFunctionNames
         ? context.options[0].assertFunctionNames
-        : ['expect']
+        : ['expect'],
     );
 
     return {
@@ -54,7 +54,7 @@ module.exports = {
           context.report({
             message: 'Test has no assertions',
             node,
-          })
+          }),
         );
       },
     };

rules/no-alias-methods.js → src/rules/no-alias-methods.js

@@ -47,7 +47,7 @@ module.exports = {
 
         // Check if the method used matches any of ours
         const methodItem = methodNames.find(
-          item => item[1] === targetNode.name
+          item => item[1] === targetNode.name,
         );
 
         if (methodItem) {

rules/no-identical-title.js → src/rules/no-identical-title.js

@@ -75,7 +75,7 @@ module.exports = {
           context,
           currentLayer.describeTitles,
           node,
-          title
+          title,
         );
       },
       'CallExpression:exit'(node) {

rules/no-jasmine-globals.js → src/rules/no-jasmine-globals.js

@@ -127,7 +127,7 @@ module.exports = {
                   return [
                     fixer.replaceText(
                       node.parent,
-                      `jest.setTimeout(${node.parent.right.value})`
+                      `jest.setTimeout(${node.parent.right.value})`,
                     ),
                   ];
                 },

rules/prefer-inline-snapshots.js → src/rules/prefer-inline-snapshots.js

@@ -19,7 +19,7 @@ module.exports = {
               return [
                 fixer.replaceText(
                   node.callee.property,
-                  'toMatchInlineSnapshot'
+                  'toMatchInlineSnapshot',
                 ),
               ];
             },
@@ -32,7 +32,7 @@ module.exports = {
               return [
                 fixer.replaceText(
                   node.callee.property,
-                  'toThrowErrorMatchingInlineSnapshot'
+                  'toThrowErrorMatchingInlineSnapshot',
                 ),
               ];
             },

rules/prefer-spy-on.js → src/rules/prefer-spy-on.js

@@ -54,11 +54,11 @@ module.exports = {
               fixer.insertTextBefore(node.left, `jest.spyOn(`),
               fixer.replaceTextRange(
                 [node.left.object.range[1], node.left.property.range[0]],
-                `, ${leftPropQuote}`
+                `, ${leftPropQuote}`,
               ),
               fixer.replaceTextRange(
                 [node.left.property.range[1], jestFnCall.range[1]],
-                `${leftPropQuote})${mockImplementation}`
+                `${leftPropQuote})${mockImplementation}`,
               ),
             ];
           },

rules/prefer-to-contain.js → src/rules/prefer-to-contain.js

@@ -39,7 +39,7 @@ const getNegationFixes = (node, sourceCode, fixer) => {
   const negationPropertyDot = sourceCode.getFirstTokenBetween(
     node.parent.object,
     node.parent.property,
-    token => token.value === '.'
+    token => token.value === '.',
   );
   const toContainFunc =
     isEqualityNegation(node) && argument(node.parent).value
@@ -63,7 +63,7 @@ const getCommonFixes = (node, sourceCode, fixer) => {
   const propertyDot = sourceCode.getFirstTokenBetween(
     includesCaller.object,
     includesCaller.property,
-    token => token.value === '.'
+    token => token.value === '.',
   );
 
   const closingParenthesis = sourceCode.getTokenAfter(containArg);
@@ -114,8 +114,8 @@ module.exports = {
               fixArr.push(
                 fixer.replaceText(
                   argument(node),
-                  sourceCode.getText(containArg)
-                )
+                  sourceCode.getText(containArg),
+                ),
               );
               return fixArr;
             },

rules/prefer-to-have-length.js → src/rules/prefer-to-have-length.js

@@ -35,7 +35,7 @@ module.exports = {
             .getFirstTokenBetween(
               node.arguments[0].object,
               node.arguments[0].property,
-              token => token.value === '.'
+              token => token.value === '.',
             );
           context.report({
             fix(fixer) {

rules/util.js → src/rules/util.js

@@ -1,7 +1,7 @@
 'use strict';
 
 const path = require('path');
-const { version } = require('../package.json');
+const { version } = require('../../package.json');
 
 const REPO_URL = 'https://github.com/jest-community/eslint-plugin-jest';
 

rules/valid-expect-in-promise.js → src/rules/valid-expect-in-promise.js

@@ -98,7 +98,7 @@ const verifyExpectWithReturn = (
   promiseCallbacks,
   node,
   context,
-  testFunctionBody
+  testFunctionBody,
 ) => {
   promiseCallbacks.some(promiseCallback => {
     if (promiseCallback && isFunction(promiseCallback)) {
@@ -156,7 +156,7 @@ module.exports = {
               [fulfillmentCallback, rejectionCallback],
               node,
               context,
-              testFunctionBody
+              testFunctionBody,
             );
           }
         }