@atlaskit/eslint-config-base/.eslintrc.js

The eslint configuration for AtlasKit components

module.exports = {
  name: '@atlaskit/eslint-config-base',
  extends: 'airbnb',
  parser: 'babel-eslint',
  env: {
    browser: true,
  },
  plugins: ['react', 'prefer-object-spread', 'compat'],
  rules: {
    // http://eslint.org/docs/rules/arrow-parens
    // Relaxed from airbnb because it conflicts with prettier
    'arrow-parens': 'off',

    // http://eslint.org/docs/rules/comma-dangle
    // Custom rules for when trailing comma's are required
    'comma-dangle': [
      'error',
      {
        arrays: 'always-multiline',
        objects: 'always-multiline',
        imports: 'always-multiline',
        exports: 'always-multiline',
        functions: 'ignore',
      },
    ],

    // https://github.com/benmosher/eslint-plugin-import/blob/master/docs/rules/extensions.md
    // When importing files you do not need to add file extensions for the following extensions
    'import/extensions': [
      'error',
      'always',
      {
        js: 'never',
        jsx: 'never',
        ts: 'never',
        tsx: 'never',
      },
    ],

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

    // http://eslint.org/docs/rules/no-plusplus
    // Allowing ++ on numbers
    'no-plusplus': 'off',

    // http://eslint.org/docs/rules/no-param-reassign
    // Cannot reassign function parameters but allowing modification
    'no-param-reassign': ['error', { props: false }],

    // https://github.com/yannickcr/eslint-plugin-react/blob/master/docs/rules/jsx-filename-extension.md
    // Allowing jsx in files with any file extension (old components have jsx but not the extension)
    'react/jsx-filename-extension': 'off',

    // https://github.com/yannickcr/eslint-plugin-react/blob/master/docs/rules/jsx-sort-props.md
    // JSX props must be in alphabetical order
    // Disabled as this is creating too much noise in logs and is not being actively addressed
    'react/jsx-sort-props': 'off',

    // https://github.com/yannickcr/eslint-plugin-react/blob/master/docs/rules/no-unknown-property.md
    // This was turned off for wc - but should be re-enabled eventually
    'react/no-unknown-property': ['off'],

    // http://eslint.org/docs/rules/no-multiple-empty-lines
    // Disallow more than 1 empty lines
    'no-multiple-empty-lines': ['error', { max: 1 }],

    // http://eslint.org/docs/rules/padded-blocks
    // Enforce no padding within blocks
    'padded-blocks': ['error', 'never'],

    // https://github.com/yannickcr/eslint-plugin-react/blob/master/docs/rules/no-unused-prop-types.md
    // Adding 'skipShapeProps' as the rule has issues with correctly handling PropTypes.shape
    'react/no-unused-prop-types': ['error', { skipShapeProps: true }],

    // https://github.com/yannickcr/eslint-plugin-react/blob/master/docs/rules/prefer-stateless-function.md
    // Opt out of preferring stateless functions
    // Rationale: https://extranet.atlassian.com/display/AtlasKit/React+component+conventions
    'react/prefer-stateless-function': 'off',

    // https://github.com/bryanrsmith/eslint-plugin-prefer-object-spread
    // Prefer spread {...} over Object.assign except for object modifications
    'prefer-object-spread/prefer-object-spread': 'error',

    // http://eslint.org/docs/rules/no-restricted-properties
    'no-restricted-properties': [
      'error',
      {
        // Disabling the use of React.Component
        // Rationale: https://extranet.atlassian.com/display/AtlasKit/React+component+conventions
        object: 'React',
        property: 'Component',
        message: 'Please use PureComponent instead.',
      },
    ],

    // https://github.com/amilajack/eslint-plugin-compat
    // Error when violating browser compatibility
    'compat/compat': 'error',

    // Disallowing the use of variables starting with `_` unless it called on `this`.
    // Allowed: `this._secret = Symbol()`
    // Not allowed: `const _secret = Symbol()`
    'no-underscore-dangle': ['error', { allowAfterThis: true }],
  },
};