.eslintrc.js

'use strict';

const path = require('path');

module.exports = {
  root: true,
  parser: 'babel-eslint',
  parserOptions: {
    ecmaVersion: 2018,
    sourceType: 'module',
    ecmaFeatures: {
      legacyDecorators: true,
    },
  },
  plugins: ['ember'],
  extends: [
    'eslint:recommended',
    'plugin:ember/recommended',
    'plugin:prettier/recommended',
  ],
  env: {
    browser: true,
  },
  rules: {},
  overrides: [
    // node files
    {
      files: [
        '.eslintrc.js',
        '.prettierrc.js',
        '.template-lintrc.js',
        'ember-cli-build.js',
        'index.js',
        'testem.js',
        'blueprints/*/index.js',
        'config/**/*.js',
        'faltest/**/*.js',
        'node-tests/**/*.js',
        'tests/dummy/config/**/*.js',
      ],
      excludedFiles: [
        'addon/**',
        'addon-test-support/**',
        'app/**',
        'tests/dummy/app/**',
      ],
      parserOptions: {
        sourceType: 'script',
      },
      env: {
        browser: false,
        node: true,
      },
      plugins: ['node'],
      extends: ['plugin:node/recommended'],
    },

    // mocha files
    {
      files: ['faltest/**/*-test.js', 'node-tests/**/*-test.js'],
      env: {
        mocha: true,
      },
    },

    // vendor files
    {
      files: ['vendor/**/*.js'],
      parserOptions: {
        ecmaVersion: 5,
        sourceType: 'script',
      },
      env: {
        amd: true,
      },
      globals: {
        Ember: 'readonly',
      },
      rules: Object.keys(
        Object.assign(
          {},
          // eslint-disable-next-line node/no-extraneous-require
          require(path.resolve(
            path.dirname(require.resolve('eslint')),
            '../conf/eslint-recommended'
          )).rules,
          require('eslint-plugin-ember').configs.recommended.rules
        )
      ).reduce((rules, rule) => {
        rules[rule] = 'off';
        return rules;
      }, {}),
    },
  ],
};