.eslintrc.js

'use strict';

module.exports = {
  root: true,
  parser: 'babel-eslint',
  parserOptions: {
    ecmaVersion: 2018,
    sourceType: 'module',
    ecmaFeatures: {
      legacyDecorators: true
    }
  },
  plugins: [
    'ember'
  ],
  extends: [
    'eslint:recommended',
    'plugin:ember/recommended'
  ],
  env: {
    browser: true
  },
  rules: {
    'ember/classic-decorator-hooks': 'error',
    'ember/classic-decorator-no-classic-methods': 'error',
    'no-unused-vars': [
      'error',
      { vars: 'all', args: 'after-used', ignoreRestSiblings: true },
    ],
    'arrow-body-style': 'off',
    'prefer-arrow-callback': 'off',
    'eol-last': ['error', 'always'],
    'no-else-return': 'warn',
    'no-lonely-if': 'warn',
    'no-unneeded-ternary': 'warn',
    'prefer-const': [
      'error',
      {
        destructuring: 'any',
        ignoreReadBeforeAssign: false,
      },
    ],
  },
  overrides: [
    // node files
    {
      files: [
        '.eslintrc.js',
        '.template-lintrc.js',
        'ember-cli-build.js',
        'index.js',
        'testem.js',
        'blueprints/*/index.js',
        'config/**/*.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']
    }
  ]
};