feat: support eslint v9

.gitattributes

@@ -0,0 +1 @@
+* text=auto eol=lf

.github/workflows/ci.yml

@@ -13,7 +13,7 @@ jobs:
 
     strategy:
       matrix:
-        node-version: [16.x, 18.x, 20.x]
+        node-version: [18.x, 20.x]
 
     steps:
       - uses: actions/checkout@v3
@@ -22,5 +22,8 @@ jobs:
         with:
           node-version: ${{ matrix.node-version }}
 
-      - run: npm install
-      - run: npm run ci
+      - name: Install pnpm
+        uses: pnpm/action-setup@v2
+
+      - run: pnpm install
+      - run: pnpm run ci

eslint.config.js

@@ -0,0 +1,72 @@
+import js from '@eslint/js';
+import pluginImport from 'eslint-plugin-import-x';
+import pluginNode from 'eslint-plugin-n';
+import configPrettier from 'eslint-config-prettier';
+
+export default [
+  {
+    ignores: ['packages/eslint-plugin-ecmascript-compat-example/*'],
+  },
+  pluginNode.configs['flat/recommended-module'],
+  {
+    languageOptions: {
+      parserOptions: {
+        ecmaVersion: 2022,
+        sourceType: 'module',
+      },
+      sourceType: 'module',
+    },
+    plugins: {
+      'import-x': pluginImport,
+    },
+    rules: {
+      ...js.configs.all.rules,
+      ...configPrettier.rules,
+      'capitalized-comments': 'off',
+      'global-require': 'off',
+      'init-declarations': 'off',
+      'line-comment-position': 'off',
+      'multiline-comment-style': 'off',
+      'no-eq-null': 'off',
+      'no-inline-comments': 'off',
+      'no-magic-numbers': 'off',
+      'no-plusplus': 'off',
+      'no-ternary': 'off',
+      'no-undefined': 'off',
+      'one-var': 'off',
+      'sort-imports': 'off', // using import/order instead
+      'sort-keys': 'off',
+      strict: 'off',
+
+      // eslint:all - Modify default options
+      eqeqeq: ['error', 'always', { null: 'never' }],
+      'func-names': ['error', 'as-needed'],
+      'func-style': ['error', 'declaration'],
+      'id-length': ['error', { exceptions: ['_', 'a', 'b', 'i'] }],
+      'no-unused-vars': ['error', { ignoreRestSiblings: true }],
+      'no-use-before-define': ['error', 'nofunc'],
+      'spaced-comment': ['error', 'always', { block: { balanced: true } }],
+
+      // eslint:all & prettier - Re-enable some of the rules
+      // that are compatible when certain options are used
+      //   (https://github.com/prettier/eslint-config-prettier#special-rules)
+      curly: 'error',
+      'max-len': ['error', { code: 1000, comments: 90, ignoreUrls: true }],
+      quotes: ['error', 'single', { avoidEscape: true, allowTemplateLiterals: false }],
+
+      // eslint:all - Rules whose default options do nothing.
+      // Options need to be compatible with Prettier.
+      'padding-line-between-statements': [
+        'error',
+        { blankLine: 'always', prev: '*', next: ['cjs-export'] },
+
+        { blankLine: 'always', prev: '*', next: 'block-like' },
+        { blankLine: 'always', prev: 'block-like', next: '*' },
+      ],
+
+      'import-x/newline-after-import': 'error',
+      'import-x/no-extraneous-dependencies': 'error',
+      'import-x/order': ['error', { 'newlines-between': 'never' }],
+    },
+  },
+];

lerna.json

@@ -1,6 +1,4 @@
 {
-  "packages": [
-    "packages/*"
-  ],
+  "npmClient": "pnpm",
   "version": "3.2.1"
 }