.eslintrc.js

module.exports = {
  parser: '@typescript-eslint/parser',
  parserOptions: {
    project: ['./tsconfig.json', './test/tsconfig.json'],
  },
  plugins: [
    '@typescript-eslint',
    'jest'
  ],
  extends: [
    'airbnb-base',
    'plugin:@typescript-eslint/recommended',
    'plugin:prettier/recommended',
    'prettier/@typescript-eslint',
    'plugin:jest/recommended'
  ],
  settings: {
    'import/resolver': {
      node: {
        extensions: ['.js', '.ts'],
      },
    },
  },
  rules: {
    'import/extensions': 0,
    'import/prefer-default-export': 0,
    'class-methods-use-this': 0,
    '@typescript-eslint/no-unused-vars': 2,
    '@typescript-eslint/no-inferrable-types': 0,
    '@typescript-eslint/explicit-member-accessibility': [
      'warn',
      { accessibility: 'no-public' },
    ],
  },
  // rules specific to testing files
  overrides: [
    {
      files: ['**/test/**/*.test.[jt]s?(x)'],
      rules: {
        '@typescript-eslint/explicit-function-return-type': 0,
        '@typescript-eslint/no-object-literal-type-assertion': 0,
        'import/no-extraneous-dependencies': [
          'error',
          { devDependencies: true },
        ],
      },
    },
  ],
};