.eslintrc.js

module.exports = {
  root: true,
  parser: '@typescript-eslint/parser',
  parserOptions: {
    project: true,
    tsconfigRootDir: __dirname,
  },
  env: {
    node: true,
  },
  extends: [
    'airbnb-base',
    'airbnb-typescript/base',
    'plugin:@typescript-eslint/recommended-type-checked',
    'plugin:@typescript-eslint/stylistic-type-checked',
    'prettier',
  ],
  rules: {
    'import/prefer-default-export': 'off',
    '@typescript-eslint/no-unused-vars': 'error',

    // Allow for-of loops, other rules are copied from airbnb-base: https://github.com/airbnb/javascript/blob/11ab37144b7f846f04f64a29b5beb6e00d74e84b/packages/eslint-config-airbnb-base/rules/style.js#L340-L358
    'no-restricted-syntax': [
      'error',
      {
        selector: 'ForInStatement',
        message:
          'for..in loops iterate over the entire prototype chain, which is virtually never what you want. Use Object.{keys,values,entries}, and iterate over the resulting array.',
      },
      {
        selector: 'LabeledStatement',
        message:
          'Labels are a form of GOTO; using them makes code confusing and hard to maintain and understand.',
      },
      {
        selector: 'WithStatement',
        message:
          '`with` is disallowed in strict mode because it makes code impossible to predict and optimize.',
      },
    ],
  },
  overrides: [
    {
      files: ['*.spec.*'],
      env: {
        jest: true,
      },
      extends: ['plugin:jest/recommended', 'plugin:jest/style'],
    },
  ],
};