.eslintrc.js

const asyncKeywordConstraintMsg =
  'The async keyword adds a `regenerator` dependency in the hls.js ES5 output not allowed in v1 due to bundle size constraints.';
const selfVsWindowGlobalMsg =
  'Use `self` instead of `window` to access the global context everywhere (including workers).';
const arrayFindCompatibilityMsg =
  'Usage of Array find method is restricted for compatibility.';
const arrayFindIndexCompatibilityMsg =
  'Usage of Array findIndex method is restricted for compatibility.';
const arrayEveryCompatibilityMsg =
  'Usage of Array every method is restricted for compatibility. Use a negative Array some check instead.';

module.exports = {
  env: { browser: true, commonjs: true, es6: true },
  globals: {
    // Allowed globals
    console: true,

    // Compile-time defines
    __VERSION__: true,
    __USE_SUBTITLES__: true,
    __USE_ALT_AUDIO__: true,
    __USE_EME_DRM__: true,
    __USE_CMCD__: true,
    __USE_CONTENT_STEERING__: true,
    __USE_VARIABLE_SUBSTITUTION__: true,
    __USE_M2TS_ADVANCED_CODECS__: true,
    __USE_MEDIA_CAPABILITIES__: true,
    __USE_INTERSTITIALS__: true,
    __USE_IFRAMES__: true,
  },
  // see https://github.com/standard/eslint-config-standard
  // 'prettier' (https://github.com/prettier/eslint-config-prettier) must be last
  extends: ['eslint:recommended', 'prettier'],
  parser: '@typescript-eslint/parser',
  parserOptions: { sourceType: 'module', project: './tsconfig.json' },
  plugins: ['@typescript-eslint', 'import', 'no-for-of-loops'],
  rules: {
    'no-restricted-globals': [
      2,
      {
        name: 'window',
        message: selfVsWindowGlobalMsg,
      },
      { name: 'SourceBuffer', message: 'Use `self.SourceBuffer`' },
      { name: 'setTimeout', message: 'Use `self.setTimeout`' },
      { name: 'setInterval', message: 'Use `self.setInterval`' },
    ],

    'import/first': 1,
    'no-var': 1,
    'no-empty': 1,
    'no-unused-vars': 'warn',
    'no-console': [1, { allow: ['assert'] }],
    'no-fallthrough': 1,
    'no-case-declarations': 2,
    'no-self-assign': 1,
    'new-cap': 1,
    'no-undefined': 0,
    'no-global-assign': 2,
    'prefer-const': 2,
    'dot-notation': 2,
    'no-void': 2,
    'no-useless-catch': 2,
    'no-prototype-builtins': 0,
    'no-for-of-loops/no-for-of-loops': 2,
  },
  overrides: [
    {
      parserOptions: { project: ['./tsconfig.json'] },
      files: ['*.ts'],
      rules: {
        'no-unused-vars': 0,
        'no-undef': 0,
        'no-use-before-define': 'off',
        'no-restricted-syntax': [
          'error',
          {
            selector: 'FunctionDeclaration[async=true]',
            message: asyncKeywordConstraintMsg,
          },
          {
            selector: 'ArrowFunctionExpression[async=true]',
            message: asyncKeywordConstraintMsg,
          },
          {
            selector: 'MethodDefinition[value.async=true]',
            message: asyncKeywordConstraintMsg,
          },
          {
            selector:
              'MemberExpression[property.name="find"][object.type="Identifier"]',
            message: arrayFindCompatibilityMsg,
          },
          {
            selector:
              'MemberExpression[property.name="findIndex"][object.type="Identifier"]',
            message: arrayFindIndexCompatibilityMsg,
          },
          {
            selector:
              'MemberExpression[property.name="every"][object.type="Identifier"]',
            message: arrayEveryCompatibilityMsg,
          },
        ],
        'import/order': [
          'warn',
          {
            alphabetize: { order: 'asc' },
            groups: [
              'builtin',
              'external',
              'internal',
              ['sibling', 'index'],
              'parent',
              'type',
            ],
            'newlines-between': 'never',
          },
        ],
        'sort-imports': [
          'error',
          { ignoreCase: true, ignoreDeclarationSort: true },
        ],
        '@typescript-eslint/no-unused-vars': [
          'warn',
          { args: 'none', caughtErrors: 'none' },
        ],
        '@typescript-eslint/prefer-optional-chain': 2,
        '@typescript-eslint/consistent-type-assertions': [
          2,
          { assertionStyle: 'as', objectLiteralTypeAssertions: 'never' },
        ],
        '@typescript-eslint/consistent-type-imports': 'error',
        '@typescript-eslint/no-import-type-side-effects': 'error',
        '@typescript-eslint/no-restricted-imports': 'error',
        '@typescript-eslint/no-floating-promises': 'error',
        '@typescript-eslint/no-misused-promises': 'error',
      },
    },
  ],
};