feat!: remove eslint v8 / eslintrc support and remove flat/ prefix from configs (#528)

* feat!: remove eslint v8 support

This change removes support for legacy rc-based configs, and moves minimum supported version to 9.0.  I've also removed the deprecated `/configs` entry point.

* use test setup file

* docs: update examples

* build: disable n/no-missing-import for md files

* build: disable n/no-missing-import for md files

---------

Co-authored-by: Bryan Mishkin <[email protected]>

Author: michaelfaith

.eslint-doc-generatorrc.js

@@ -9,13 +9,6 @@ const config = {
     'rules-recommended',
     'tests',
     'tests-recommended',
-    'flat/recommended',
-    'flat/all',
-    'flat/all-type-checked',
-    'flat/rules',
-    'flat/rules-recommended',
-    'flat/tests',
-    'flat/tests-recommended',
   ],
   postprocess: async (content, path) =>
     prettier.format(content, {

.github/workflows/main.yml

@@ -34,28 +34,17 @@ jobs:
       - uses: actions/checkout@v4
       - uses: actions/setup-node@v4
         with:
-          node-version: "lts/*"
+          node-version: 'lts/*'
       - run: npm install
       - run: npm run lint
 
-  eslint8:
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v4
-      - uses: actions/setup-node@v4
-        with:
-          node-version: "lts/*"
-      - run: npm install
-      - run: npm install --save-dev eslint@8
-      - run: npm test
-
   test-remote:
     name: eslint-remote-tester
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
       - uses: actions/setup-node@v4
         with:
-          node-version: "lts/*"
+          node-version: 'lts/*'
       - run: npm install
       - run: npm run test:remote

README.md

@@ -6,8 +6,6 @@ An ESLint plugin for linting ESLint plugins. Rules written in CJS, ESM, and Type
 
 - [Installation](#installation)
 - [Usage](#usage)
-  - [**.eslintrc.json**](#eslintrcjson)
-  - [`eslint.config.js` (requires eslint\>=v8.23.0)](#eslintconfigjs-requires-eslintv8230)
 - [Rules](#rules)
   - [Rules](#rules-1)
   - [Tests](#tests)
@@ -42,25 +40,14 @@ Here's an example ESLint configuration that:
 - Enables the `recommended` configuration
 - Enables an optional/non-recommended rule
 
-Note: you might need to set `sourceType` to `script` (most users) (use `module` for ESM/TypeScript).
-
-### <a name='eslintrc'></a>**[.eslintrc.json](https://eslint.org/docs/latest/use/configure/configuration-files)**
-
-```json
-{
-  "extends": ["plugin:eslint-plugin/recommended"],
-  "rules": {
-    "eslint-plugin/require-meta-docs-description": "error"
-  }
-}
-```
-
-### <a name='flat'></a>[`eslint.config.js`](https://eslint.org/docs/latest/use/configure/configuration-files-new) (requires eslint>=v8.23.0)
+Note: you might need to set `sourceType` to `module` or `script` depending on your codebase.
 
 ```js
-const eslintPlugin = require('eslint-plugin-eslint-plugin');
-module.exports = [
-  eslintPlugin.configs['flat/recommended'],
+// eslint.config.js
+import eslintPlugin from 'eslint-plugin-eslint-plugin';
+
+export default [
+  eslintPlugin.configs.recommended,
   {
     rules: {
       'eslint-plugin/require-meta-docs-description': 'error',
@@ -141,54 +128,29 @@ The list of recommended rules will only change in a major release of this plugin
 
 ### <a name='Presetusage'></a>Preset usage
 
-Both flat and eslintrc configs are supported. For example, to enable the `recommended` preset, use:
-
-eslint.config.js
+Example of applying the `recommended` config to all files.
 
 ```js
-const eslintPlugin = require('eslint-plugin-eslint-plugin');
-module.exports = [eslintPlugin.configs['flat/recommended']];
-```
+// eslint.config.js
+import eslintPlugin from 'eslint-plugin-eslint-plugin';
 
-.eslintrc.json
-
-```json
-{
-  "extends": ["plugin:eslint-plugin/recommended"]
-}
+export default [eslintPlugin.configs.recommended];
 ```
 
 Or to apply linting only to the appropriate rule or test files:
 
-eslint.config.js
-
 ```js
-const eslintPlugin = require('eslint-plugin-eslint-plugin');
-module.exports = [
+// eslint.config.js
+import eslintPlugin from 'eslint-plugin-eslint-plugin';
+
+export default [
   {
     files: ['lib/rules/*.{js,ts}'],
-    ...eslintPlugin.configs['flat/rules-recommended'],
+    ...eslintPlugin.configs['rules-recommended'],
   },
   {
     files: ['tests/lib/rules/*.{js,ts}'],
-    ...eslintPlugin.configs['flat/tests-recommended'],
+    ...eslintPlugin.configs['tests-recommended'],
   },
 ];
 ```
-
-.eslintrc.js
-
-```json
-{
-  "overrides": [
-    {
-      "files": ["lib/rules/*.{js,ts}"],
-      "extends": ["plugin:eslint-plugin/rules-recommended"]
-    },
-    {
-      "files": ["tests/lib/rules/*.{js,ts}"],
-      "extends": ["plugin:eslint-plugin/tests-recommended"]
-    }
-  ]
-}
-```

configs/all-type-checked.js

@@ -96,29 +96,54 @@ module.exports = {
 }
 ```
 
+```js
+// eslint.config.js
+import eslintPlugin from 'eslint-plugin-eslint-plugin';
+
+export default [
+  {
+    plugins: { 'eslint-plugin': eslintPlugin },
+    rules: {
+      'eslint-plugin/require-meta-docs-url': [
+        'error',
+        {
+          pattern:
+            'https://github.com/eslint-community/eslint-plugin-eslint-plugin/blob/master/docs/rules/{{name}}.md',
+        },
+      ],
+    },
+  },
+];
+```
+
 If you set the `pattern` option, this rule adds `meta.docs.url` property automatically when you execute `eslint --fix` command.
 
 ## Version specific URL
 
-If you want to enforce version-specific URLs, it's feasible easily with `.eslintrc.js` and `npm version <type>` script.
+If you want to enforce version-specific URLs, it's feasible easily with `eslint.config.js` and `npm version <type>` script.
 For example:
 
-**.eslintrc.js**:
+**eslint.config.js**:
 
 ```js
-// const version = require("./package.json").version;
-
-module.exports = {
-  plugins: ['eslint-plugin'],
-  rules: {
-    'eslint-plugin/require-meta-docs-url': [
-      'error',
-      {
-        pattern: `path/to/v${version}/docs/rules/{{name}}.md`,
-      },
-    ],
+import eslintPlugin from 'eslint-plugin-eslint-plugin';
+import packageMetadata from './package.json' with { type: 'json' };
+
+const { version } = packageMetadata;
+
+export default [
+  {
+    plugins: { 'eslint-plugin': eslintPlugin },
+    rules: {
+      'eslint-plugin/require-meta-docs-url': [
+        'error',
+        {
+          pattern: `path/to/v${version}/docs/rules/{{name}}.md`,
+        },
+      ],
+    },
   },
-};
+];
 ```
 
 **package.json**:

configs/all.js

@@ -4,7 +4,7 @@ import js from '@eslint/js';
 import { FlatCompat } from '@eslint/eslintrc';
 import markdown from 'eslint-plugin-markdown';
 import pluginN from 'eslint-plugin-n';
-import eslintPluginConfig from 'eslint-plugin-eslint-plugin/configs/all';
+import eslintPlugin from './lib/index.js';
 
 const dirname = path.dirname(fileURLToPath(import.meta.url));
 const compat = new FlatCompat({
@@ -46,9 +46,9 @@ export default [
   {
     // Apply eslint-plugin rules to our own rules/tests (but not docs).
     files: ['lib/**/*.js', 'tests/**/*.js'],
-    plugins: eslintPluginConfig.plugins,
+    plugins: { 'eslint-plugin': eslintPlugin },
     rules: {
-      ...eslintPluginConfig.rules,
+      ...eslintPlugin.configs.all.rules,
       'eslint-plugin/no-meta-schema-default': 'off', // TODO: enable once https://github.com/bmish/eslint-doc-generator/issues/513 is fixed and released
       'eslint-plugin/report-message-format': ['error', '^[^a-z].*.$'],
       'eslint-plugin/require-meta-docs-url': [
@@ -77,6 +77,8 @@ export default [
 
       '@eslint-community/eslint-comments/require-description': 'off',
 
+      'n/no-missing-import': 'off',
+
       'unicorn/filename-case': 'off',
     },
   },

configs/recommended.js

@@ -105,31 +105,14 @@ const plugin = {
   configs: {}, // assigned later
 };
 
-// eslintrc configs
+// configs
 Object.assign(
   plugin.configs,
   Object.keys(configFilters).reduce((configs, configName) => {
     return Object.assign(configs, {
       [configName]: {
-        plugins: ['eslint-plugin'],
-        rules: Object.fromEntries(
-          Object.keys(allRules)
-            .filter((ruleName) => configFilters[configName](allRules[ruleName]))
-            .map((ruleName) => [`${PLUGIN_NAME}/${ruleName}`, 'error']),
-        ),
-      },
-    });
-  }, {}),
-);
-
-// flat configs
-Object.assign(
-  plugin.configs,
-  Object.keys(configFilters).reduce((configs, configName) => {
-    return Object.assign(configs, {
-      [`flat/${configName}`]: {
-        name: `eslint-plugin/flat/${configName}`,
-        plugins: { 'eslint-plugin': plugin },
+        name: `${PLUGIN_NAME}/${configName}`,
+        plugins: { [PLUGIN_NAME]: plugin },
         rules: Object.fromEntries(
           Object.keys(allRules)
             .filter((ruleName) => configFilters[configName](allRules[ruleName]))

configs/rules-recommended.js

@@ -7,7 +7,6 @@
   "type": "module",
   "exports": {
     ".": "./lib/index.js",
-    "./configs/*": "./configs/*.js",
     "./package.json": "./package.json"
   },
   "license": "MIT",
@@ -24,8 +23,8 @@
     "update:eslint-docs": "eslint-doc-generator"
   },
   "files": [
-    "lib/",
-    "configs/"
+    "CHANGELOG.md",
+    "lib/"
   ],
   "keywords": [
     "eslint",
@@ -79,7 +78,7 @@
     "vitest": "^3.2.4"
   },
   "peerDependencies": {
-    "eslint": ">=8.23.0"
+    "eslint": ">=9.0.0"
   },
   "engines": {
     "node": "^18.18.0 || ^20.9.0 || >=21.1.0"