module.exports = {
  env: {
    es6: true
  },
  parserOptions: {
    ecmaVersion: 6,
    sourceType: 'module'
  },
  plugins: [
    'import'
  ],

  settings: {
    'import/resolver': {
      node: {
        extensions: ['.js', '.json']
      }
    },
    'import/extensions': [
      '.js',
      '.jsx',
    ],
    'import/core-modules': [
    ],
    'import/ignore': [
      'node_modules',
      '\\.(coffee|scss|css|less|hbs|svg|json)$',
    ],
  },

  rules: {
    // Static analysis:

    // ensure imports point to files/modules that can be resolved
    // https://github.com/benmosher/eslint-plugin-import/blob/master/docs/rules/no-unresolved.md
    'import/no-unresolved': ['error', { commonjs: true, caseSensitive: true }],

    // ensure named imports coupled with named exports
    // https://github.com/benmosher/eslint-plugin-import/blob/master/docs/rules/named.md#when-not-to-use-it
    'import/named': 'off',

    // ensure default import coupled with default export
    // https://github.com/benmosher/eslint-plugin-import/blob/master/docs/rules/default.md#when-not-to-use-it
    'import/default': 'off',

    // https://github.com/benmosher/eslint-plugin-import/blob/master/docs/rules/namespace.md
    'import/namespace': 'off',

    // Helpful warnings:

    // disallow invalid exports, e.g. multiple defaults
    // https://github.com/benmosher/eslint-plugin-import/blob/master/docs/rules/export.md
    'import/export': 'error',

    // do not allow a default import name to match a named export
    // https://github.com/benmosher/eslint-plugin-import/blob/master/docs/rules/no-named-as-default.md
    'import/no-named-as-default': 'error',

    // warn on accessing default export property names that are also named exports
    // https://github.com/benmosher/eslint-plugin-import/blob/master/docs/rules/no-named-as-default-member.md
    'import/no-named-as-default-member': 'error',

    // disallow use of jsdoc-marked-deprecated imports
    // https://github.com/benmosher/eslint-plugin-import/blob/master/docs/rules/no-deprecated.md
    'import/no-deprecated': 'off',

    // Forbid the use of extraneous packages
    // https://github.com/benmosher/eslint-plugin-import/blob/master/docs/rules/no-extraneous-dependencies.md
    // paths are treated both as absolute paths, and relative to process.cwd()
    'import/no-extraneous-dependencies': ['error', {
      devDependencies: [
        'test/**', // tape, common npm pattern
        'tests/**', // also common npm pattern
        'spec/**', // mocha, rspec-like pattern
        '**/__tests__/**', // jest pattern
        'test.js', // repos with a single test file
        'test-*.js', // repos with multiple top-level test files
        '**/*.test.js', // tests where the extension denotes that it is a test
        '**/*.spec.js', // tests where the extension denotes that it is a test
        '**/webpack.config.js', // webpack config
        '**/webpack.config.*.js', // webpack config
        '**/rollup.config.js', // rollup config
        '**/gulpfile.js', // gulp config
        '**/gulpfile.*.js', // gulp config
        '**/Gruntfile', // grunt config
      ],
      optionalDependencies: false,
    }],

    // Forbid mutable exports
    // https://github.com/benmosher/eslint-plugin-import/blob/master/docs/rules/no-mutable-exports.md
    'import/no-mutable-exports': 'error',

    // Module systems:

    // disallow require()
    // https://github.com/benmosher/eslint-plugin-import/blob/master/docs/rules/no-commonjs.md
    'import/no-commonjs': 'off',

    // disallow AMD require/define
    // https://github.com/benmosher/eslint-plugin-import/blob/master/docs/rules/no-amd.md
    'import/no-amd': 'error',

    // No Node.js builtin modules
    // https://github.com/benmosher/eslint-plugin-import/blob/master/docs/rules/no-nodejs-modules.md
    // TODO: enable?
    'import/no-nodejs-modules': 'off',

    // Style guide:

    // disallow non-import statements appearing before import statements
    // https://github.com/benmosher/eslint-plugin-import/blob/master/docs/rules/first.md
    'import/first': ['error', 'absolute-first'],

    // disallow non-import statements appearing before import statements
    // https://github.com/benmosher/eslint-plugin-import/blob/master/docs/rules/imports-first.md
    // deprecated: use `import/first`
    'import/imports-first': 'off',

    // disallow duplicate imports
    // https://github.com/benmosher/eslint-plugin-import/blob/master/docs/rules/no-duplicates.md
    'import/no-duplicates': 'error',

    // disallow namespace imports
    // TODO: enable?
    // https://github.com/benmosher/eslint-plugin-import/blob/master/docs/rules/no-namespace.md
    'import/no-namespace': 'off',

    // Ensure consistent use of file extension within the import path
    // https://github.com/benmosher/eslint-plugin-import/blob/master/docs/rules/extensions.md
    'import/extensions': ['error', 'always', {
      js: 'never',
      jsx: 'never',
    }],

    // Enforce a convention in module import order
    // https://github.com/benmosher/eslint-plugin-import/blob/master/docs/rules/order.md
    // TODO: enable?
    'import/order': ['off', {
      groups: ['builtin', 'external', 'internal', 'parent', 'sibling', 'index'],
      'newlines-between': 'never',
    }],

    // Require a newline after the last import/require in a group
    // https://github.com/benmosher/eslint-plugin-import/blob/master/docs/rules/newline-after-import.md
    'import/newline-after-import': 'error',

    // Require modules with a single export to use a default export
    // https://github.com/benmosher/eslint-plugin-import/blob/master/docs/rules/prefer-default-export.md
    'import/prefer-default-export': 'error',

    // Restrict which files can be imported in a given folder
    // https://github.com/benmosher/eslint-plugin-import/blob/master/docs/rules/no-restricted-paths.md
    'import/no-restricted-paths': 'off',

    // Forbid modules to have too many dependencies
    // https://github.com/benmosher/eslint-plugin-import/blob/master/docs/rules/max-dependencies.md
    'import/max-dependencies': ['off', { max: 10 }],

    // Forbid import of modules using absolute paths
    // https://github.com/benmosher/eslint-plugin-import/blob/master/docs/rules/no-absolute-path.md
    'import/no-absolute-path': 'error',

    // Forbid require() calls with expressions
    // https://github.com/benmosher/eslint-plugin-import/blob/master/docs/rules/no-dynamic-require.md
    'import/no-dynamic-require': 'error',

    // prevent importing the submodules of other modules
    // https://github.com/benmosher/eslint-plugin-import/blob/master/docs/rules/no-internal-modules.md
    'import/no-internal-modules': ['off', {
      allow: [],
    }],

    // Warn if a module could be mistakenly parsed as a script by a consumer
    // leveraging Unambiguous JavaScript Grammar
    // https://github.com/benmosher/eslint-plugin-import/blob/master/docs/rules/unambiguous.md
    // this should not be enabled until this proposal has at least been *presented* to TC39.
    // At the moment, it's not a thing.
    'import/unambiguous': 'off',

    // Forbid Webpack loader syntax in imports
    // https://github.com/benmosher/eslint-plugin-import/blob/master/docs/rules/no-webpack-loader-syntax.md
    'import/no-webpack-loader-syntax': 'error',

    // Prevent unassigned imports
    // https://github.com/benmosher/eslint-plugin-import/blob/master/docs/rules/no-unassigned-import.md
    // importing for side effects is perfectly acceptable, if you need side effects.
    'import/no-unassigned-import': 'off',

    // Prevent importing the default as if it were named
    // https://github.com/benmosher/eslint-plugin-import/blob/master/docs/rules/no-named-default.md
    'import/no-named-default': 'error',
  },
};
