.eslintrc.js

module.exports = {
  'parser': 'babel-eslint',

  'extends': ['eslint:recommended'],

  'parserOptions': {
    'ecmaVersion': 6,
    'sourceType': 'module',
    'ecmaFeatures': {
      'impliedStrict': true,
      'jsx': true
    }
  },

  'env': {
    'browser': true,
    'node': true,
    'es6': true,
    'mocha': true,
    'jquery': true
  },

  'plugins': [
    'react'
  ],

  'globals': {
    'define': true,
    'expect': true,
    'it': true,
    'describe': true,
    'API_URL': true
  },

  'rules': {
    // Possible Errors
    'comma-dangle': 'error',
    'no-cond-assign': 'error',
    'no-console': 'warn',
    'no-constant-condition': 'error',
    'no-control-regex': 'error',
    'no-debugger': 'warn',
    'no-dupe-args': 'error',
    'no-dupe-keys': 'error',
    'no-duplicate-case': 'error',
    'no-empty': 'error',
    'no-empty-character-class': 'error',
    'no-ex-assign': 'error',
    'no-extra-boolean-cast': 'error',
    'no-extra-parens': 'off',
    'no-extra-semi': 'error',
    'no-func-assign': 'error',
    'no-inner-declarations': 'error',
    'no-invalid-regexp': 'error',
    'no-irregular-whitespace': ['error', {
      'skipStrings': true,
      'skipTemplates': true
    }],
    'no-negated-in-lhs': 'error',
    'no-obj-calls': 'error',
    'no-regex-spaces': 'error',
    'no-sparse-arrays': 'error',
    'no-unexpected-multiline': 'error',
    'no-unreachable': 'error',
    'no-unsafe-finally': 'error',
    'use-isnan': 'error',
    'valid-jsdoc': 'off',
    'valid-typeof': 'error',

    // Best Practices
    'accessor-pairs': 'error',
    'array-callback-return': 'error',
    'block-scoped-var': 'error',
    'complexity': 'off',
    'consistent-return': 'error',
    'curly': ['error', 'all'],
    'default-case': 'error',
    'dot-location': ['error', 'property'],
    'dot-notation': 'error',
    'eqeqeq': 'error',
    'guard-for-in': 'error',
    'no-alert': 'error',
    'no-caller': 'error',
    'no-case-declarations': 'error',
    'no-div-regex': 'error',
    'no-else-return': 'error',
    'no-empty-function': 'error',
    'no-empty-pattern': 'error',
    'no-eq-null': 'error',
    'no-eval': 'error',
    'no-extend-native': 'error',
    'no-extra-bind': 'error',
    'no-extra-label': 'error',
    'no-fallthrough': 'error',
    'no-floating-decimal': 'error',
    'no-implicit-coercion': 'error',
    'no-implicit-globals': 'error',
    'no-implied-eval': 'error',
    'no-invalid-this': 'off',
    'no-iterator': 'error',
    'no-labels': 'error',
    'no-lone-blocks': 'error',
    'no-loop-func': 'error',
    'no-magic-numbers': ['off', {
      'enforceConst': true,
      'detectObjects': true
    }],
    'no-multi-spaces': 'error',
    'no-multi-str': 'error',
    'no-native-reassign': 'error',
    'no-new': 'error',
    'no-new-func': 'error',
    'no-new-wrappers': 'error',
    'no-octal': 'error',
    'no-octal-escape': 'error',
    'no-param-reassign': 'error',
    'no-proto': 'error',
    'no-redeclare': 'error',
    'no-return-assign': 'error',
    'no-script-url': 'error',
    'no-self-assign': 'error',
    'no-self-compare': 'error',
    'no-sequences': 'error',
    'no-throw-literal': 'off',
    'no-unmodified-loop-condition': 'error',
    'no-unused-expressions': 'error',
    'no-unused-labels': 'error',
    'no-useless-call': 'error',
    'no-useless-concat': 'error',
    'no-useless-escape': 'error',
    'no-void': 'error',
    'no-warning-comments': 'warn',
    'no-with': 'error',
    'radix': 'error',
    'vars-on-top': 'error',
    'wrap-iife': 'error',
    'yoda': ['error', 'never'],

    // Strict Mode
    'strict': ['error', 'never'],

    // Variables
    'init-declarations': ['error', 'always'],
    'no-catch-shadow': 'error',
    'no-delete-var': 'error',
    'no-label-var': 'error',
    'no-restricted-globals': 'error',
    'no-shadow': 'error',
    'no-shadow-restricted-names': 'error',
    'no-undef': 'error',
    'no-undef-init': 'error',
    'no-undefined': 'off',
    'no-unused-vars': 'error',
    'no-use-before-define': 'off',

    // Node.js and CommonJS
    'callback-return': 'error',
    'global-require': 'off',
    'handle-callback-err': 'off',
    'no-mixed-requires': 'off',
    'no-new-require': 'off',
    'no-path-concat': 'off',
    'no-process-env': 'off',
    'no-process-exit': 'error',
    'no-restricted-modules': 'off',
    'no-sync': 'off',

    // Stylistic Issues
    'array-bracket-spacing': ['error', 'always'],
    'block-spacing': ['error', 'always'],
    'brace-style': ['error', '1tbs'],
    'camelcase': ['error', {
      'properties': 'always'
    }],
    'comma-dangle': ['error', 'never'],
    'comma-spacing': ['error', {
      'before': false,
      'after': true
    }],
    'comma-style': ['error', 'last'],
    'computed-property-spacing': ['error', 'never'],
    'consistent-this': ['error', 'this'],
    'eol-last': 'error',
    'func-names': ['error', 'never'],
    'func-style': 'off',
    'id-blacklist': 'off',
    'id-length': ['off', {
      'min': 3,
      'exceptions': ['_', 'id', 'to', 'x', 'y']
    }],
    'id-match': 'off',
    'indent': ['error', 2],
    'jsx-quotes': ['error', 'prefer-double'],
    'key-spacing': ['error', {
      'beforeColon': false,
      'afterColon': true,
      'mode': 'strict'
    }],
    'keyword-spacing': ['error', {
      'before': true,
      'after': true
    }],
    'linebreak-style': ['error', 'unix'],
    'lines-around-comment': 'off',
    'max-depth': ['error', 4],
    'max-len': ['error', 120],
    'max-lines': ['warn', 200],
    'max-nested-callbacks': ['error', 5],
    'max-params': ['error', 4],
    'max-statements': ['warn', 30],
    'max-statements-per-line': ['error', {
      'max': 1
    }],
    'new-cap': ['error', {
      'newIsCap': true,
      'capIsNew': false,
      'properties': true
    }],
    'new-parens': 'error',
    'newline-after-var': 'off',
    'newline-before-return': 'off',
    'newline-per-chained-call': 'off',
    'no-array-constructor': 'error',
    'no-bitwise': 'error',
    'no-continue': 'error',
    'no-inline-comments': 'off',
    'no-lonely-if': 'error',
    'no-mixed-operators': 'off',
    'no-mixed-spaces-and-tabs': 'error',
    'no-multiple-empty-lines': 'error',
    'no-negated-condition': 'error',
    'no-nested-ternary': 'error',
    'no-new-object': 'error',
    'no-plusplus': 'off',
    'no-restricted-syntax': ['error', 'WithStatement'],
    'no-spaced-func': 'error',
    'no-ternary': 'off',
    'no-trailing-spaces': 'error',
    'no-underscore-dangle': ['error', {
      'allow': ['_']
    }],
    'no-unneeded-ternary': 'error',
    'no-whitespace-before-property': 'error',
    'object-curly-newline': 'off',
    'object-curly-spacing': ['error', 'always'],
    'object-property-newline': ['error', {
      'allowMultiplePropertiesPerLine': true
    }],
    'one-var': ['error', 'never'],
    'one-var-declaration-per-line': ['error', 'always'],
    'operator-assignment': ['error', 'always'],
    'operator-linebreak': ['off', 'none', {
      'overrides': {
        '?': 'before',
        ':': 'before'
      }
    }],
    'padded-blocks': ['error', 'never'],
    'quote-props': ['error', 'as-needed'],
    'quotes': ['error', 'single'],
    'require-jsdoc': 'off',
    'semi': ['error', 'always'],
    'semi-spacing': ['error', {
      'before': false,
      'after': true
    }],
    'sort-vars': 'error',
    'space-before-blocks': ['error', 'always'],
    'space-before-function-paren': ['error', 'never'],
    'space-in-parens': ['error', 'never'],
    'space-infix-ops': 'error',
    'space-unary-ops': 'error',
    'spaced-comment': ['error', 'always'],
    'unicode-bom': ['error', 'never'],
    'wrap-regex': 'off',

    // ECMAScript 6
    'arrow-body-style': ['error', 'as-needed'],
    'arrow-parens': ['error', 'always'],
    'arrow-spacing': ['error', {
      'before': true,
      'after': true
    }],
    'constructor-super': 'error',
    'generator-star-spacing': ['error', {
      'before': false,
      'after': true
    }],
    'no-class-assign': 'error',
    'no-confusing-arrow': 'off',
    'no-const-assign': 'error',
    'no-dupe-class-members': 'error',
    'no-duplicate-imports': 'error',
    'no-new-symbol': 'error',
    'no-restricted-imports': 'off',
    'no-this-before-super': 'error',
    'no-useless-computed-key': 'error',
    'no-useless-constructor': 'error',
    'no-useless-rename': 'error',
    'no-var': 'error',
    'object-shorthand': ['error', 'always', {
      'avoidQuotes': true
    }],
    'prefer-arrow-callback': 'error',
    'prefer-const': 'error',
    'prefer-reflect': 'error',
    'prefer-rest-params': 'error',
    'prefer-spread': 'error',
    'prefer-template': 'error',
    'require-yield': 'error',
    'rest-spread-spacing': ['error', 'never'],
    'sort-imports': 'off',
    'template-curly-spacing': ['error', 'never'],
    'yield-star-spacing': ['error', {
      'before': false,
      'after': true
    }],

    // React
    'react/display-name': 'off',
    'react/forbid-prop-types': ['off', {
      'forbid': ['any']
    }],
    'react/jsx-no-comment-textnodes': 'error',
    'react/no-danger': 'error',
    'react/no-deprecated': 'error',
    'react/no-did-mount-set-state': 'error',
    'react/no-did-update-set-state': 'error',
    'react/no-direct-mutation-state': 'error',
    'react/no-is-mounted': 'error',
    'react/no-multi-comp': ['error', {
      'ignoreStateless': true
    }],
    'react/no-render-return-value': 'error',
    // 'react/no-set-state': 'error',
    'react/no-string-refs': 'error',
    'react/no-unknown-property': 'error',
    'react/prefer-es6-class': 'error',
    // 'react/prefer-stateless-function': 'error',
    'react/prop-types': 'error',
    'react/react-in-jsx-scope': 'error',
    // 'react/require-optimization': 'error',
    'react/require-render-return': 'error',
    'react/self-closing-comp': 'error',
    'react/sort-comp': ['error', {
      'order': [
        'static-methods',
        'lifecycle',
        '/^on.+$/',
        'everything-else',
        'render',
        '/^render.+/'
      ]
    }],
    'react/sort-prop-types': ['error', {
      'ignoreCase': true,
      'callbacksLast': true
    }],
    'react/no-unused-prop-types': 'error',
    'react/jsx-wrap-multilines': 'error',

    // JSX-specific rules
    'react/jsx-boolean-value': ['error', 'always'],
    'react/jsx-closing-bracket-location': ['error', {
      'nonEmpty': 'after-props',
      'selfClosing': 'after-props'
    }],
    'react/jsx-curly-spacing': ['error', 'never'],
    'react/jsx-equals-spacing': ['error', 'never'],
    'react/jsx-filename-extension': ['error', {
      'extensions': ['.js']
    }],
    'react/jsx-first-prop-new-line': ['error', 'multiline'],
    'react/jsx-handler-names': ['error', {
      'eventHandlerPrefix': 'on',
      'eventHandlerPropPrefix': 'on'
    }],
    'react/jsx-indent': ['error', 2],
    'react/jsx-indent-props': ['error', 2],
    'react/jsx-key': 'error',
    'react/jsx-max-props-per-line': 'off',
    'react/jsx-no-bind': 'off',
    'react/jsx-no-duplicate-props': 'error',
    'react/jsx-no-literals': 'off',
    'react/jsx-no-target-blank': 'error',
    'react/jsx-no-undef': 'error',
    'react/jsx-pascal-case': 'error',
    'react/jsx-sort-props': 'off',
    'react/jsx-space-before-closing': ['error', 'always'],
    'react/jsx-uses-react': 'error',
    'react/jsx-uses-vars': 'error'
  }
};