[New] support eslint 9

.github/workflows/node-4+.yml

@@ -36,6 +36,7 @@ jobs:
           - macos-latest
         node-version: ${{ fromJson(needs.matrix.outputs.latest) }}
         eslint:
+          - 9
           - 8
           - 7
           - 6
@@ -63,34 +64,58 @@ jobs:
             env:
               TS_PARSER: 2
         exclude:
+          - node-version: 16
+            eslint: 9
+          - node-version: 15
+            eslint: 9
           - node-version: 15
             eslint: 8
+          - node-version: 14
+            eslint: 9
+          - node-version: 13
+            eslint: 9
           - node-version: 13
             eslint: 8
+          - node-version: 12
+            eslint: 9
+          - node-version: 11
+            eslint: 9
           - node-version: 11
             eslint: 8
+          - node-version: 10
+            eslint: 9
           - node-version: 10
             eslint: 8
+          - node-version: 9
+            eslint: 9
           - node-version: 9
             eslint: 8
           - node-version: 9
             eslint: 7
+          - node-version: 8
+            eslint: 9
           - node-version: 8
             eslint: 8
           - node-version: 8
             eslint: 7
+          - node-version: 7
+            eslint: 9
           - node-version: 7
             eslint: 8
           - node-version: 7
             eslint: 7
           - node-version: 7
             eslint: 6
+          - node-version: 6
+            eslint: 9
           - node-version: 6
             eslint: 8
           - node-version: 6
             eslint: 7
           - node-version: 6
             eslint: 6
+          - node-version: 5
+            eslint: 9
           - node-version: 5
             eslint: 8
           - node-version: 5
@@ -99,6 +124,8 @@ jobs:
             eslint: 6
           - node-version: 5
             eslint: 5
+          - node-version: 4
+            eslint: 9
           - node-version: 4
             eslint: 8
           - node-version: 4

CHANGELOG.md

@@ -7,6 +7,7 @@ This change log adheres to standards from [Keep a CHANGELOG](https://keepachange
 ## [Unreleased]
 
 ### Added
+- support eslint v9 ([#2996], thanks [@G-Rath] [@michaelfaith])
 - [`order`]: allow validating named imports ([#3043], thanks [@manuth])
 
 ### Fixed
@@ -15,6 +16,7 @@ This change log adheres to standards from [Keep a CHANGELOG](https://keepachange
 - [`export`]: False positive for exported overloaded functions in TS ([#3065], thanks [@liuxingbaoyu])
 - `exportMap`: export map cache is tainted by unreliable parse results ([#3062], thanks [@michaelfaith])
 - `exportMap`: improve cacheKey when using flat config ([#3072], thanks [@michaelfaith])
+- adjust "is source type module" checks for flat config ([#2996], thanks [@G-Rath])
 
 ### Changed
 - [Docs] [`no-relative-packages`]: fix typo ([#3066], thanks [@joshuaobrien])
@@ -1165,6 +1167,7 @@ for info on changes for earlier releases.
 [#3011]: https://github.com/import-js/eslint-plugin-import/pull/3011
 [#3004]: https://github.com/import-js/eslint-plugin-import/pull/3004
 [#2998]: https://github.com/import-js/eslint-plugin-import/pull/2998
+[#2996]: https://github.com/import-js/eslint-plugin-import/pull/2996
 [#2993]: https://github.com/import-js/eslint-plugin-import/pull/2993
 [#2991]: https://github.com/import-js/eslint-plugin-import/pull/2991
 [#2989]: https://github.com/import-js/eslint-plugin-import/pull/2989

package.json

@@ -76,7 +76,7 @@
     "chai": "^4.3.10",
     "cross-env": "^4.0.0",
     "escope": "^3.6.0",
-    "eslint": "^2 || ^3 || ^4 || ^5 || ^6 || ^7.2.0 || ^8",
+    "eslint": "^2 || ^3 || ^4 || ^5 || ^6 || ^7.2.0 || ^8 || ^9",
     "eslint-doc-generator": "^1.6.1",
     "eslint-import-resolver-node": "file:./resolvers/node",
     "eslint-import-resolver-typescript": "^1.0.2 || ^1.1.1",
@@ -106,7 +106,7 @@
     "typescript-eslint-parser": "^15 || ^20 || ^22"
   },
   "peerDependencies": {
-    "eslint": "^2 || ^3 || ^4 || ^5 || ^6 || ^7.2.0 || ^8"
+    "eslint": "^2 || ^3 || ^4 || ^5 || ^6 || ^7.2.0 || ^8 || ^9"
   },
   "dependencies": {
     "@rtsao/scc": "^1.1.0",

src/core/sourceType.js

@@ -0,0 +1,12 @@
+/**
+ * @param {import('eslint').Rule.RuleContext} context
+ * @returns 'module' | 'script' | 'commonjs' | undefined
+ */
+export default function sourceType(context) {
+  if ('sourceType' in context.parserOptions) {
+    return context.parserOptions.sourceType;
+  }
+  if ('languageOptions' in context && context.languageOptions) {
+    return context.languageOptions.sourceType;
+  }
+}

src/rules/no-default-export.js

@@ -1,6 +1,7 @@
 import { getSourceCode } from 'eslint-module-utils/contextCompat';
 
 import docsUrl from '../docsUrl';
+import sourceType from '../core/sourceType';
 
 module.exports = {
   meta: {
@@ -15,7 +16,7 @@ module.exports = {
 
   create(context) {
     // ignore non-modules
-    if (context.parserOptions.sourceType !== 'module') {
+    if (sourceType(context) !== 'module') {
       return {};
     }
 

src/rules/no-named-export.js

@@ -1,3 +1,4 @@
+import sourceType from '../core/sourceType';
 import docsUrl from '../docsUrl';
 
 module.exports = {
@@ -13,7 +14,7 @@ module.exports = {
 
   create(context) {
     // ignore non-modules
-    if (context.parserOptions.sourceType !== 'module') {
+    if (sourceType(context) !== 'module') {
       return {};
     }
 

src/rules/unambiguous.js

@@ -5,6 +5,7 @@
 
 import { isModule } from 'eslint-module-utils/unambiguous';
 import docsUrl from '../docsUrl';
+import sourceType from '../core/sourceType';
 
 module.exports = {
   meta: {
@@ -19,7 +20,7 @@ module.exports = {
 
   create(context) {
     // ignore non-modules
-    if (context.parserOptions.sourceType !== 'module') {
+    if (sourceType(context) !== 'module') {
       return {};
     }
 

tests/files/issue210.config.flat.js

@@ -0,0 +1,3 @@
+exports.languageOptions = {
+  sourceType: 'module',
+}

tests/files/just-json-files/eslint.config.js

@@ -0,0 +1,28 @@
+var jsonPlugin = require('eslint-plugin-json');
+
+if (!jsonPlugin.processors.json) {
+  jsonPlugin.processors.json = jsonPlugin.processors['.json'];
+}
+
+module.exports = [
+  {
+    files: ['tests/files/just-json-files/*.json'],
+    plugins:{
+      json: jsonPlugin,
+    },
+    processor: 'json/json',
+    rules: Object.assign(
+      {},
+      {
+        'import/no-unused-modules': [
+          'error',
+          {
+            'missingExports': false,
+            'unusedExports': true,
+          },
+        ],
+      },
+      jsonPlugin.configs.recommended.rules
+    )
+  },
+];

tests/src/cli.js

@@ -15,17 +15,29 @@ describe('CLI regression tests', function () {
     let cli;
     before(function () {
       if (ESLint) {
-        eslint = new ESLint({
-          useEslintrc: false,
-          overrideConfigFile: './tests/files/issue210.config.js',
-          rulePaths: ['./src/rules'],
-          overrideConfig: {
-            rules: {
-              named: 2,
+        if (semver.satisfies(eslintPkg.version, '>= 9')) {
+          eslint = new ESLint({
+            overrideConfigFile: './tests/files/issue210.config.flat.js',
+            overrideConfig: {
+              rules: {
+                'import/named': 2,
+              },
             },
-          },
-          plugins: { 'eslint-plugin-import': importPlugin },
-        });
+            plugins: { 'eslint-plugin-import': importPlugin },
+          });
+        } else {
+          eslint = new ESLint({
+            useEslintrc: false,
+            overrideConfigFile: './tests/files/issue210.config.js',
+            rulePaths: ['./src/rules'],
+            overrideConfig: {
+              rules: {
+                named: 2,
+              },
+            },
+            plugins: { 'eslint-plugin-import': importPlugin },
+          });
+        }
       } else {
         cli = new CLIEngine({
           useEslintrc: false,
@@ -56,13 +68,20 @@ describe('CLI regression tests', function () {
         this.skip();
       } else {
         if (ESLint) {
-          eslint = new ESLint({
-            useEslintrc: false,
-            overrideConfigFile: './tests/files/just-json-files/.eslintrc.json',
-            rulePaths: ['./src/rules'],
-            ignore: false,
-            plugins: { 'eslint-plugin-import': importPlugin },
-          });
+          if (semver.satisfies(eslintPkg.version, '>= 9')) {
+            eslint = new ESLint({
+              overrideConfigFile: './tests/files/just-json-files/eslint.config.js',
+              plugins: { 'eslint-plugin-import': importPlugin },
+            });
+          } else {
+            eslint = new ESLint({
+              useEslintrc: false,
+              overrideConfigFile: './tests/files/just-json-files/.eslintrc.json',
+              rulePaths: ['./src/rules'],
+              ignore: false,
+              plugins: { 'eslint-plugin-import': importPlugin },
+            });
+          }
         } else {
           cli = new CLIEngine({
             useEslintrc: false,

tests/src/rule-tester.js

@@ -1,5 +1,47 @@
+import { RuleTester } from 'eslint';
+import { version as eslintVersion } from 'eslint/package.json';
+import semver from 'semver';
+
+export const usingFlatConfig = semver.major(eslintVersion) >= 9;
+
 export function withoutAutofixOutput(test) {
-  return { ...test, output: test.code };
+  return { ...test, ...usingFlatConfig || { output: test.code } };
+}
+
+class FlatCompatRuleTester {
+  constructor(testerConfig = { parserOptions: { sourceType: 'script' } }) {
+    this._tester = new RuleTester(FlatCompatRuleTester._flatCompat(testerConfig));
+  }
+
+  run(ruleName, rule, tests) {
+    this._tester.run(ruleName, rule, {
+      valid: tests.valid.map((t) => FlatCompatRuleTester._flatCompat(t)),
+      invalid: tests.invalid.map((t) => FlatCompatRuleTester._flatCompat(t)),
+    });
+  }
+
+  static _flatCompat(config) {
+    if (!config || !usingFlatConfig || typeof config !== 'object') {
+      return config;
+    }
+
+    const { parser, parserOptions = {}, languageOptions = {}, ...remainingConfig  } = config;
+    const { ecmaVersion, sourceType, ...remainingParserOptions } = parserOptions;
+    const parserObj = typeof parser === 'string' ? require(parser) : parser;
+
+    return {
+      ...remainingConfig,
+      languageOptions: {
+        ...languageOptions,
+        ...parserObj ? { parser: parserObj } : {},
+        ...ecmaVersion ? { ecmaVersion } : {},
+        ...sourceType ? { sourceType } : {},
+        parserOptions: {
+          ...remainingParserOptions,
+        },
+      },
+    };
+  }
 }
 
-export { RuleTester } from 'eslint';
+export { FlatCompatRuleTester as RuleTester };

tests/src/rules/named.js

@@ -1,5 +1,5 @@
 import { test, SYNTAX_CASES, getTSParsers, testFilePath, testVersion, parsers } from '../utils';
-import { RuleTester } from '../rule-tester';
+import { RuleTester, usingFlatConfig } from '../rule-tester';
 import path from 'path';
 
 import { CASE_SENSITIVE_FS } from 'eslint-module-utils/resolve';
@@ -32,7 +32,7 @@ ruleTester.run('named', rule, {
       settings: { 'import/resolve': { extensions: ['.js', '.jsx'] } } }),
 
     // validate that eslint-disable-line silences this properly
-    test({ code: 'import {a, b, d} from "./common"; // eslint-disable-line named' }),
+    test({ code: `import {a, b, d} from "./common"; // eslint-disable-line ${usingFlatConfig ? 'rule-to-test/' : ''}named` }),
 
     test({ code: 'import { foo, bar } from "./re-export-names"' }),
 

tests/src/rules/namespace.js

@@ -2,7 +2,7 @@ import { test, SYNTAX_CASES, getTSParsers, testVersion, testFilePath, parsers }
 import { RuleTester } from '../rule-tester';
 import flatMap from 'array.prototype.flatmap';
 
-const ruleTester = new RuleTester({ env: { es6: true } });
+const ruleTester = new RuleTester({ parserOptions: { ecmaVersion: 6 } });
 const rule = require('rules/namespace');
 
 function error(name, namespace) {

tests/src/rules/no-unused-modules.js

@@ -288,8 +288,8 @@ describe('dynamic imports', function () {
 
   // test for unused exports with `import()`
   ruleTester.run('no-unused-modules', rule, {
-    valid: [
-      test({
+    valid: [].concat(
+      testVersion('< 9', () => ({
         options: unusedExportsOptions,
         code: `
             export const a = 10
@@ -300,10 +300,10 @@ describe('dynamic imports', function () {
             `,
         parser: parsers.BABEL_OLD,
         filename: testFilePath('./no-unused-modules/exports-for-dynamic-js.js'),
-      }),
-    ],
-    invalid: [
-      test({
+      })),
+    ),
+    invalid: [].concat(
+      testVersion('< 9', () => ({
         options: unusedExportsOptions,
         code: `
         export const a = 10
@@ -319,8 +319,8 @@ describe('dynamic imports', function () {
           error(`exported declaration 'b' not used within other modules`),
           error(`exported declaration 'c' not used within other modules`),
           error(`exported declaration 'default' not used within other modules`),
-        ] }),
-    ],
+        ] })),
+    ),
   });
   typescriptRuleTester.run('no-unused-modules', rule, {
     valid: [