upgrade to eslint v9

Author: kylehoehns

.eslintignore

@@ -0,0 +1,120 @@
+import js from '@eslint/js';
+import tseslint from 'typescript-eslint';
+import onlyWarn from 'eslint-plugin-only-warn';
+
+export default tseslint.config(
+  {
+    ignores: ['.husky/**', 'dist/**'],
+  },
+  {
+    plugins: {
+      onlyWarn,
+    },
+  },
+  js.configs.recommended,
+  {
+    files: ['**/*.js'],
+    languageOptions: {
+      ecmaVersion: 'latest',
+      sourceType: 'module',
+      globals: {
+        process: 'readonly',
+        console: 'readonly',
+        __dirname: 'readonly',
+        __filename: 'readonly',
+        Buffer: 'readonly',
+        module: 'readonly',
+        require: 'readonly',
+        exports: 'readonly',
+      },
+    },
+    rules: {
+      'no-unused-vars': [
+        'warn',
+        {
+          argsIgnorePattern: '_.*',
+          varsIgnorePattern: '_.*',
+        },
+      ],
+    },
+  },
+  {
+    files: ['**/*.ts'],
+    ignores: ['**/*.d.ts', '**/*.test.ts'],
+    extends: [...tseslint.configs.recommended],
+    languageOptions: {
+      ecmaVersion: 'latest',
+      sourceType: 'module',
+      parser: tseslint.parser,
+      parserOptions: {
+        project: true,
+      },
+      globals: {
+        process: 'readonly',
+        console: 'readonly',
+        __dirname: 'readonly',
+        __filename: 'readonly',
+        Buffer: 'readonly',
+        module: 'readonly',
+        require: 'readonly',
+        exports: 'readonly',
+      },
+    },
+    rules: {
+      '@typescript-eslint/no-unused-vars': [
+        'warn',
+        {
+          argsIgnorePattern: '_.*',
+          varsIgnorePattern: '_.*',
+        },
+      ],
+    },
+  },
+  {
+    files: ['**/*.d.ts'],
+    extends: [...tseslint.configs.recommended],
+    languageOptions: {
+      ecmaVersion: 'latest',
+      sourceType: 'module',
+      parser: tseslint.parser,
+    },
+    rules: {
+      '@typescript-eslint/no-unused-vars': 'off',
+    },
+  },
+  {
+    files: ['**/*.test.ts'],
+    extends: [...tseslint.configs.recommended],
+    languageOptions: {
+      ecmaVersion: 'latest',
+      sourceType: 'module',
+      parser: tseslint.parser,
+      parserOptions: {
+        project: true,
+      },
+      globals: {
+        process: 'readonly',
+        console: 'readonly',
+        __dirname: 'readonly',
+        __filename: 'readonly',
+        Buffer: 'readonly',
+        module: 'readonly',
+        require: 'readonly',
+        exports: 'readonly',
+        describe: 'readonly',
+        it: 'readonly',
+        test: 'readonly',
+        expect: 'readonly',
+        beforeEach: 'readonly',
+        afterEach: 'readonly',
+        beforeAll: 'readonly',
+        afterAll: 'readonly',
+        jest: 'readonly',
+      },
+    },
+    rules: {
+      '@typescript-eslint/no-explicit-any': 'off',
+      '@typescript-eslint/no-non-null-assertion': 'off',
+    },
+  },
+);

.eslintrc.yml

@@ -16,7 +16,7 @@
     "build": "tsup src/index.ts --target node22 --sourcemap",
     "build:docker": "docker build -t sai/hacker-rank-queue -f docker/Dockerfile .",
     "lint": "pnpm lint:no-fix --fix",
-    "lint:no-fix": "eslint . --ext .js,.ts --max-warnings 0",
+    "lint:no-fix": "eslint .",
     "format": "prettier --write .",
     "format:check": "prettier --check .",
     "test": "TZ=America/Chicago jest",
@@ -27,25 +27,27 @@
     "preinstall": "npx only-allow pnpm"
   },
   "devDependencies": {
+    "@eslint/js": "^9.37.0",
     "@slack/types": "2.18.0",
     "@types/chance": "1.1.7",
     "@types/express": "^5.0.3",
     "@types/google-spreadsheet": "3.3.2",
     "@types/jest": "30.0.0",
     "@types/node": "22.18.12",
     "@types/node-cron": "3.0.11",
-    "@typescript-eslint/eslint-plugin": "6.21.0",
-    "@typescript-eslint/parser": "6.21.0",
+    "@typescript-eslint/eslint-plugin": "8.45.0",
+    "@typescript-eslint/parser": "8.45.0",
     "chance": "1.1.13",
-    "eslint": "8.57.1",
+    "eslint": "9.37.0",
     "eslint-plugin-only-warn": "1.1.0",
     "husky": "9.1.7",
     "jest": "30.2.0",
     "prettier": "3.6.2",
     "ts-jest": "29.4.5",
     "ts-node": "10.9.2",
     "tslib": "2.8.1",
-    "typescript": "5.9.3"
+    "typescript": "5.9.3",
+    "typescript-eslint": "^8.45.0"
   },
   "dependencies": {
     "@slack/bolt": "4.5.0",