Upgrade eslint from 8 to 9

.eslintignore

@@ -31,3 +31,4 @@ starters/apps/base
 starters/apps/library
 starters/templates
 vite.config.ts
+packages/eslint-plugin-qwik

eslint.config.mjs

@@ -0,0 +1,52 @@
+import eslint from '@eslint/js';
+import tseslint from 'typescript-eslint';
+import { fileURLToPath } from 'url';
+import { dirname } from 'path';
+import typescript from '@typescript-eslint/eslint-plugin';
+import { includeIgnoreFile } from '@eslint/compat';
+const __dirname = dirname(fileURLToPath(import.meta.url));
+import globals from 'globals';
+const gitignorePath = fileURLToPath(import.meta.resolve('./.eslintignore'));
+const gitignorePathConfig = includeIgnoreFile(gitignorePath);
+export default tseslint.config(
+  gitignorePathConfig,
+  {
+    languageOptions: {
+      parserOptions: {
+        sourceType: 'module',
+        ecmaFeatures: {
+          jsx: true,
+        },
+        globals: {
+          ...globals.node,
+          ...globals.es2021,
+          ...globals.browser,
+        },
+        ecmaVersion: 2021,
+        project: ['./tsconfig.json'],
+        tsconfigRootDir: __dirname,
+      },
+    },
+    plugins: { '@typescript-eslint': typescript },
+    rules: {
+      '@typescript-eslint/no-explicit-any': 'off',
+      '@typescript-eslint/explicit-module-boundary-types': 'off',
+      '@typescript-eslint/no-inferrable-types': 'off',
+      '@typescript-eslint/no-non-null-assertion': 'off',
+      '@typescript-eslint/no-empty-interface': 'off',
+      '@typescript-eslint/no-namespace': 'off',
+      '@typescript-eslint/no-empty-function': 'off',
+      '@typescript-eslint/no-this-alias': 'off',
+      '@typescript-eslint/ban-types': 'off',
+      '@typescript-eslint/ban-ts-comment': 'off',
+      'prefer-spread': 'off',
+      'no-case-declarations': 'off',
+      'no-console': 'off',
+      '@typescript-eslint/no-unused-vars': ['error'],
+      '@typescript-eslint/consistent-type-imports': 'warn',
+      '@typescript-eslint/no-unnecessary-condition': 'warn',
+    },
+  },
+  eslint.configs.recommended,
+  tseslint.configs.recommended
+);

package.json

@@ -115,6 +115,7 @@
     "@changesets/get-github-info": "0.6.0",
     "@changesets/types": "6.0.0",
     "@clack/prompts": "0.7.0",
+    "@eslint/compat": "^1.2.6",
     "@eslint/eslintrc": "3.1.0",
     "@mdx-js/mdx": "3.0.1",
     "@microsoft/api-documenter": "7.24.2",
@@ -127,7 +128,7 @@
     "@types/brotli": "1.3.4",
     "@types/bun": "1.1.6",
     "@types/cross-spawn": "6.0.6",
-    "@types/eslint": "8.56.10",
+    "@types/eslint": "9.6.1",
     "@types/express": "4.17.21",
     "@types/node": "20.14.11",
     "@types/path-browserify": "1.0.2",
@@ -136,8 +137,7 @@
     "@types/semver": "7.5.8",
     "@types/tmp": "0.2.6",
     "@types/which-pm-runs": "1.0.2",
-    "@typescript-eslint/eslint-plugin": "7.16.1",
-    "@typescript-eslint/parser": "7.16.1",
+    "@typescript-eslint/eslint-plugin": "8.23.0",
     "all-contributors-cli": "6.26.1",
     "brotli": "1.3.3",
     "concurrently": "8.2.2",
@@ -146,11 +146,12 @@
     "csstype": "3.1.3",
     "dotenv": "16.4.5",
     "esbuild": "0.20.2",
-    "eslint": "8.57.0",
+    "eslint": "9.16.0",
     "eslint-plugin-no-only-tests": "3.1.0",
     "eslint-plugin-qwik": "workspace:^",
     "execa": "8.0.1",
     "express": "4.20.0",
+    "globals": "15.13.0",
     "install": "0.13.0",
     "memfs": "4.14.0",
     "monaco-editor": "0.45.0",
@@ -172,6 +173,7 @@
     "tree-kill": "1.2.2",
     "tsx": "4.19.1",
     "typescript": "5.4.5",
+    "typescript-eslint": "8.23.0",
     "undici": "*",
     "vfile": "6.0.2",
     "vite": "5.3.5",

packages/docs/src/routes/demo/eslint.config.mjs

@@ -0,0 +1,51 @@
+import eslint from '@eslint/js';
+import tseslint from 'typescript-eslint';
+import { fileURLToPath } from 'url';
+import { dirname } from 'path';
+import typescript from '@typescript-eslint/eslint-plugin';
+const __dirname = dirname(fileURLToPath(import.meta.url));
+import globals from 'globals';
+
+export default tseslint.config(
+  eslint.configs.recommended,
+  tseslint.configs.recommended,
+  {
+    languageOptions: {
+      parserOptions: {
+        sourceType: 'module',
+        ecmaFeatures: {
+          jsx: true,
+        },
+        globals: {
+          ...globals.node,
+          ...globals.es2021,
+          ...globals.browser,
+        },
+        ecmaVersion: 2021,
+        project: ['./tsconfig.json'],
+        tsconfigRootDir: __dirname,
+      },
+    },
+    plugins: {
+      '@typescript-eslint': typescript,
+    },
+    rules: {
+      '@typescript-eslint/no-explicit-any': 'off',
+      '@typescript-eslint/explicit-module-boundary-types': 'off',
+      '@typescript-eslint/no-inferrable-types': 'off',
+      '@typescript-eslint/no-non-null-assertion': 'off',
+      '@typescript-eslint/no-empty-interface': 'off',
+      '@typescript-eslint/no-namespace': 'off',
+      '@typescript-eslint/no-empty-function': 'off',
+      '@typescript-eslint/no-this-alias': 'off',
+      '@typescript-eslint/ban-types': 'off',
+      '@typescript-eslint/ban-ts-comment': 'off',
+      'prefer-spread': 'off',
+      'no-case-declarations': 'off',
+      'no-console': 'off',
+      '@typescript-eslint/no-unused-vars': ['error'],
+      '@typescript-eslint/consistent-type-imports': 'warn',
+      'qwik/no-react-props': 'off',
+    },
+  }
+);

packages/docs/src/routes/demo/state/no-serialize/eslint.config.mjs

@@ -0,0 +1,54 @@
+import eslint from '@eslint/js';
+import tseslint from 'typescript-eslint';
+import { fileURLToPath } from 'url';
+import { dirname } from 'path';
+import typescript from '@typescript-eslint/eslint-plugin';
+import qwik from 'eslint-plugin-qwik';
+const __dirname = dirname(fileURLToPath(import.meta.url));
+import globals from 'globals';
+
+export default tseslint.config(
+  eslint.configs.recommended,
+  tseslint.configs.recommended,
+  qwik.configs.recommended,
+  {
+    languageOptions: {
+      parserOptions: {
+        sourceType: 'module',
+        ecmaFeatures: {
+          jsx: true,
+        },
+        globals: {
+          ...globals.node,
+          ...globals.es2021,
+          ...globals.browser,
+        },
+        ecmaVersion: 2021,
+        project: ['../../tsconfig.json'],
+        tsconfigRootDir: __dirname,
+      },
+    },
+    plugins: {
+      '@typescript-eslint': typescript,
+    },
+    rules: {
+      '@typescript-eslint/no-explicit-any': 'off',
+      '@typescript-eslint/explicit-module-boundary-types': 'off',
+      '@typescript-eslint/no-inferrable-types': 'off',
+      '@typescript-eslint/no-non-null-assertion': 'off',
+      '@typescript-eslint/no-empty-interface': 'off',
+      '@typescript-eslint/no-namespace': 'off',
+      '@typescript-eslint/no-empty-function': 'off',
+      '@typescript-eslint/no-this-alias': 'off',
+      '@typescript-eslint/ban-types': 'off',
+      '@typescript-eslint/ban-ts-comment': 'off',
+      'prefer-spread': 'off',
+      'no-case-declarations': 'off',
+      'no-console': 'off',
+      '@typescript-eslint/no-unused-vars': ['error'],
+      '@typescript-eslint/consistent-type-imports': 'warn',
+      'qwik/no-react-props': 'off',
+      'qwik/valid-lexical-scope': 'off',
+    },
+  }
+);

packages/eslint-plugin-qwik/package.json

@@ -14,7 +14,8 @@
     "@types/estree": "1.0.5",
     "@typescript-eslint/rule-tester": "8.14.0",
     "redent": "4.0.0",
-    "@types/eslint": "9.6.1"
+    "@types/eslint": "9.6.1",
+    "@types/jsx-ast-utils": "3.3.1"
   },
   "engines": {
     "node": ">=16.8.0 <18.0.0 || >=18.11"

packages/eslint-plugin-qwik/src/jsxAtag.ts

@@ -1,6 +1,12 @@
 import { ESLintUtils, TSESTree } from '@typescript-eslint/utils';
 
-const createRule = ESLintUtils.RuleCreator(() => 'https://qwik.dev/docs/advanced/dollar/');
+interface RuleOptions {
+  recommended: string;
+}
+
+const createRule = ESLintUtils.RuleCreator<RuleOptions>(
+  () => 'https://qwik.dev/docs/advanced/dollar/'
+);
 
 export const jsxAtag = createRule({
   defaultOptions: [],

packages/eslint-plugin-qwik/src/jsxImg.ts

@@ -1,7 +1,10 @@
 import { ESLintUtils, TSESTree } from '@typescript-eslint/utils';
-import { QwikEslintExamples } from '../examples';
+import type { QwikEslintExamples } from '../examples';
+interface RuleOptions {
+  recommended: string;
+}
 
-const createRule = ESLintUtils.RuleCreator(
+const createRule = ESLintUtils.RuleCreator<RuleOptions>(
   (name) => `https://qwik.dev/docs/advanced/eslint/#${name}`
 );
 
@@ -148,7 +151,7 @@ function imgImportName(value: string) {
   return `Img${toPascalCase(value)}`;
 }
 
-function toPascalCase(string) {
+function toPascalCase(string: string) {
   return `${string}`
     .toLowerCase()
     .replace(new RegExp(/[-_]+/, 'g'), ' ')