[New] support eslint 8.x

Co-authored-by: Michaël De Boey <[email protected]>
Co-authored-by: Jordan Harband <[email protected]>

Author: MichaelDeBoey

.github/workflows/node-4+.yml

@@ -26,6 +26,7 @@ jobs:
       matrix:
         node-version: ${{ fromJson(needs.matrix.outputs.latest) }}
         eslint:
+          - 8
           - 7
           - 6
           - 5
@@ -45,24 +46,46 @@ jobs:
             babel-eslint: 10
           - node-version: 4
             babel-eslint: 9
+          - node-version: 15
+            eslint: 8
+          - node-version: 13
+            eslint: 8
+          - node-version: 11
+            eslint: 8
+          - node-version: 11
+            eslint: 7
+          - node-version: 10
+            eslint: 8
+          - node-version: 9
+            eslint: 8
           - node-version: 9
             eslint: 7
+          - node-version: 8
+            eslint: 8
           - node-version: 8
             eslint: 7
+          - node-version: 7
+            eslint: 8
           - node-version: 7
             eslint: 7
           - node-version: 7
             eslint: 6
+          - node-version: 6
+            eslint: 8
           - node-version: 6
             eslint: 7
           - node-version: 6
             eslint: 6
+          - node-version: 5
+            eslint: 8
           - node-version: 5
             eslint: 7
           - node-version: 5
             eslint: 6
           - node-version: 5
             eslint: 5
+          - node-version: 4
+            eslint: 8
           - node-version: 4
             eslint: 7
           - node-version: 4

package.json

@@ -56,7 +56,7 @@
     "@typescript-eslint/parser": "^2.34.0 || ^3.10.1 || ^4.0.0 || ^5.0.0",
     "aud": "^1.1.5",
     "babel-eslint": "^8 || ^9 || ^10.1.0",
-    "eslint": "^3 || ^4 || ^5 || ^6 || ^7",
+    "eslint": "^3 || ^4 || ^5 || ^6 || ^7 || ^8",
     "eslint-config-airbnb-base": "^14.2.1",
     "eslint-plugin-eslint-plugin": "^2.3.0 || ^3.5.3 || ^4.0.1",
     "eslint-plugin-import": "^2.25.2",
@@ -72,7 +72,7 @@
     "typescript-eslint-parser": "^20.1.1"
   },
   "peerDependencies": {
-    "eslint": "^3 || ^4 || ^5 || ^6 || ^7"
+    "eslint": "^3 || ^4 || ^5 || ^6 || ^7 || ^8"
   },
   "engines": {
     "node": ">=4"

tests/helpers/getESLintCoreRule.js

@@ -0,0 +1,11 @@
+'use strict';
+
+const version = require('eslint/package.json').version;
+const semver = require('semver');
+
+const isESLintV8 = semver.major(version) >= 8;
+
+// eslint-disable-next-line global-require, import/no-dynamic-require, import/no-unresolved
+const getESLintCoreRule = (ruleId) => (isESLintV8 ? require('eslint/use-at-your-own-risk').builtinRules.get(ruleId) : require(`eslint/lib/rules/${ruleId}`));
+
+module.exports = getESLintCoreRule;

tests/helpers/parsers.js

@@ -56,7 +56,7 @@ const parsers = {
       const es = test.parserOptions && test.parserOptions.ecmaVersion;
 
       function addComment(testObject, parser) {
-        const extraComment = `\n// features: [${Array.from(features).join(',')}], parser: ${parser}, parserOptions: ${testObject.parserOptions}`;
+        const extraComment = `\n// features: [${Array.from(features).join(',')}], parser: ${parser}, parserOptions: ${JSON.stringify(testObject.parserOptions)}`;
         return Object.assign(
           {},
           testObject,
@@ -94,7 +94,14 @@ const parsers = {
       const tsNew = !skipTS && !features.has('no-ts-new');
 
       return [].concat(
-        skipBase ? [] : addComment(test, 'default'),
+        skipBase ? [] : addComment(
+          Object.assign({}, test, features.has('class fields') && {
+            parserOptions: Object.assign({}, test.parserOptions, {
+              ecmaVersion: Math.max((test.parserOptions && test.parserOptions.ecmaVersion) || 0, 2022),
+            }),
+          }),
+          'default'
+        ),
         skipOldBabel ? [] : addComment(Object.assign({}, test, { parser: parsers.BABEL_ESLINT }), 'babel-eslint'),
         skipNewBabel ? [] : addComment(Object.assign({}, test, {
           parser: parsers['@BABEL_ESLINT'],

tests/lib/rules/destructuring-assignment.js

@@ -596,7 +596,6 @@ ruleTester.run('destructuring-assignment', rule, {
           );
         };
       `,
-      parser: parsers.BABEL_ESLINT,
       errors: [
         {
           messageId: 'useDestructAssignment',

tests/lib/rules/jsx-no-undef.js

@@ -29,8 +29,8 @@ const parserOptions = {
 // -----------------------------------------------------------------------------
 
 const ruleTester = new RuleTester({ parserOptions });
-const linter = ruleTester.linter || eslint.linter;
-linter.defineRule('no-undef', require('eslint/lib/rules/no-undef'));
+const linter = ruleTester.linter || eslint.linter || eslint.Linter;
+linter.defineRule('no-undef', require('../../helpers/getESLintCoreRule')('no-undef'));
 
 ruleTester.run('jsx-no-undef', rule, {
   valid: parsers.all([

tests/lib/rules/jsx-no-useless-fragment.js

@@ -8,12 +8,10 @@
 // Requirements
 // -----------------------------------------------------------------------------
 
-const eslint = require('eslint');
+const RuleTester = require('eslint').RuleTester;
 const rule = require('../../../lib/rules/jsx-no-useless-fragment');
 const parsers = require('../../helpers/parsers');
 
-const RuleTester = eslint.RuleTester;
-
 const parserOptions = {
   ecmaVersion: 2018,
   ecmaFeatures: {

tests/lib/rules/jsx-uses-react.js

@@ -10,7 +10,7 @@
 // -----------------------------------------------------------------------------
 
 const eslint = require('eslint');
-const rule = require('eslint/lib/rules/no-unused-vars');
+const rule = require('../../helpers/getESLintCoreRule')('no-unused-vars');
 
 const RuleTester = eslint.RuleTester;
 
@@ -35,7 +35,7 @@ const settings = {
 // -----------------------------------------------------------------------------
 
 const ruleTester = new RuleTester({ parserOptions });
-const linter = ruleTester.linter || eslint.linter;
+const linter = ruleTester.linter || eslint.linter || eslint.Linter;
 linter.defineRule('jsx-uses-react', require('../../../lib/rules/jsx-uses-react'));
 
 ruleTester.run('no-unused-vars', rule, {

tests/lib/rules/jsx-uses-vars.js

@@ -10,8 +10,8 @@
 // -----------------------------------------------------------------------------
 
 const eslint = require('eslint');
-const ruleNoUnusedVars = require('eslint/lib/rules/no-unused-vars');
-const rulePreferConst = require('eslint/lib/rules/prefer-const');
+const ruleNoUnusedVars = require('../../helpers/getESLintCoreRule')('no-unused-vars');
+const rulePreferConst = require('../../helpers/getESLintCoreRule')('prefer-const');
 
 const RuleTester = eslint.RuleTester;
 
@@ -30,7 +30,7 @@ const parserOptions = {
 // -----------------------------------------------------------------------------
 
 const ruleTester = new RuleTester({ parserOptions });
-const linter = ruleTester.linter || eslint.linter;
+const linter = ruleTester.linter || eslint.linter || eslint.Linter;
 linter.defineRule('jsx-uses-vars', require('../../../lib/rules/jsx-uses-vars'));
 
 ruleTester.run('no-unused-vars', ruleNoUnusedVars, {

tests/lib/rules/no-unused-prop-types.js

@@ -234,9 +234,6 @@ ruleTester.run('no-unused-prop-types', rule, {
         }
       `,
       features: ['class fields', 'optional chaining'],
-      parserOptions: {
-        ecmaVersion: 2020,
-      },
     },
     {
       code: `
@@ -775,9 +772,6 @@ ruleTester.run('no-unused-prop-types', rule, {
         }
       `,
       features: ['class fields', 'optional chaining'],
-      parserOptions: {
-        ecmaVersion: 2020,
-      },
     },
     {
       code: `