eslint.config.base.mjs

/**
 * Shareable ESLint config for Playwright TypeScript projects.
 * Single source of truth: used by this repo (via eslint.config.mjs) and by consumers (vasu-playwright-utils/eslint).
 *
 * @example
 * // eslint.config.mjs (in your project)
 * import playwrightLibConfig from 'vasu-playwright-utils/eslint';
 * export default [
 *   ...playwrightLibConfig,
 *   { rules: { 'playwright/no-focused-test': 'warn' } },
 * ];
 */

import typescript from '@typescript-eslint/eslint-plugin';
import typescriptParser from '@typescript-eslint/parser';
import prettier from 'eslint-plugin-prettier';
import importPlugin from 'eslint-plugin-import';
import jsdoc from 'eslint-plugin-jsdoc';
import playwright from 'eslint-plugin-playwright';
import js from '@eslint/js';
import process from 'node:process';

// Works in this repo and when imported from other projects (consumer's cwd)
const projectRoot = process.cwd();

export default [
  {
    ignores: [
      'node_modules/**',
      'dist/**',
      'build/**',
      'coverage/**',
      '.husky/**',
      '**/*.js',
      'package-lock.json',
    ],
  },
  js.configs.recommended,
  {
    files: ['**/*.ts'],
    languageOptions: {
      parser: typescriptParser,
      parserOptions: {
        project: './tsconfig.json',
        tsconfigRootDir: projectRoot,
      },
      globals: {
        console: 'readonly',
        process: 'readonly',
        Buffer: 'readonly',
        __dirname: 'readonly',
        __filename: 'readonly',
        global: 'readonly',
        module: 'readonly',
        require: 'readonly',
        exports: 'readonly',
      },
    },
    plugins: {
      '@typescript-eslint': typescript,
      prettier,
      import: importPlugin,
      jsdoc,
      playwright,
    },
    settings: { 'import/resolver': { typescript: { alwaysTryTypes: true } } },
    rules: {
      // Prettier Rules
      'prettier/prettier': 'error',
      'no-trailing-spaces': 'error',
      'no-multiple-empty-lines': ['error', { max: 1, maxEOF: 0 }],
      'eol-last': ['error', 'always'],

      // TypeScript Rules - Base
      ...typescript.configs['eslint-recommended'].overrides[0].rules,
      ...typescript.configs.recommended.rules,
      '@typescript-eslint/no-unsafe-assignment': 'warn',
      '@typescript-eslint/no-unsafe-member-access': 'warn',
      '@typescript-eslint/no-unsafe-return': 'warn',
      '@typescript-eslint/no-unsafe-call': 'warn',
      '@typescript-eslint/no-floating-promises': 'error',
      '@typescript-eslint/no-unnecessary-type-assertion': 'error',
      '@typescript-eslint/no-explicit-any': 'warn',
      '@typescript-eslint/explicit-module-boundary-types': 'off',

      // TypeScript Rules - Additional Strict Rules
      '@typescript-eslint/no-unused-vars': [
        'error',
        { argsIgnorePattern: '^_', varsIgnorePattern: '^_' },
      ],
      '@typescript-eslint/no-unused-expressions': 'error',
      '@typescript-eslint/no-empty-function': 'warn',
      '@typescript-eslint/prefer-nullish-coalescing': 'error',
      '@typescript-eslint/prefer-optional-chain': 'error',
      '@typescript-eslint/prefer-as-const': 'error',
      '@typescript-eslint/no-non-null-assertion': 'warn',
      '@typescript-eslint/no-duplicate-enum-values': 'error',
      '@typescript-eslint/no-inferrable-types': [
        'error',
        { ignoreParameters: false, ignoreProperties: false },
      ],

      // Import Rules
      'import/no-unresolved': 'error',
      'import/named': 'error',
      'import/default': 'error',
      'import/no-absolute-path': 'error',
      'import/no-self-import': 'error',
      'import/first': 'error',
      'import/no-mutable-exports': 'error',
      // Declaration order: builtin → external → internal → parent → sibling → index (auto-fix via import/order)
      'import/order': [
        'error',
        {
          groups: ['builtin', 'external', 'internal', 'parent', 'sibling', 'index', 'type'],
          'newlines-between': 'never',
          alphabetize: { order: 'asc', caseInsensitive: true },
          pathGroups: [
            { pattern: '@/**', group: 'internal', position: 'before' },
          ],
          pathGroupsExcludedImportTypes: ['builtin'],
        },
      ],
      // Member order within named imports only (e.g. { b, a } → { a, b }); declaration order handled by import/order
      'sort-imports': ['error', { ignoreDeclarationSort: true }],

      // General Rules - Best Practices
      'require-await': 'off',
      '@typescript-eslint/require-await': 'error',
      '@typescript-eslint/await-thenable': 'error',
      '@typescript-eslint/no-misused-promises': 'error',
      complexity: ['warn', { max: 11 }],
      'no-console': ['warn', { allow: ['warn', 'error', 'info'] }],
      'no-debugger': 'error',
      'no-var': 'error',
      'prefer-const': 'error',
      'prefer-template': 'error',
      'object-shorthand': 'error',
      'no-lonely-if': 'error',
      'no-useless-return': 'error',
      'no-nested-ternary': 'warn',
      eqeqeq: ['error', 'always', { null: 'ignore' }],
      'no-throw-literal': 'error',

      // JSDoc Rules
      'jsdoc/check-alignment': 'off',
      'jsdoc/check-indentation': 'off',

      // Playwright recommended rules
      ...playwright.configs['playwright-test'].rules,

      // Playwright Rules
      'playwright/missing-playwright-await': 'error',
      'playwright/no-focused-test': 'error',
      'playwright/valid-expect': 'error',
      'playwright/prefer-web-first-assertions': 'error',
      'playwright/no-useless-await': 'error',
      'playwright/no-page-pause': 'error',
      'playwright/no-element-handle': 'error',
      'playwright/no-eval': 'error',
      'playwright/prefer-to-be': 'error',
      'playwright/prefer-to-contain': 'error',
      'playwright/prefer-to-have-length': 'error',
      'playwright/no-wait-for-timeout': 'warn',
      'playwright/no-useless-not': 'warn',
      'playwright/require-top-level-describe': 'off',
      'playwright/expect-expect': 'off',
      'playwright/no-conditional-in-test': 'off',
      'playwright/no-skipped-test': 'off',
      'playwright/consistent-spacing-between-blocks': 'off',
    },
  },
];