eslint-plugin-react

===================

React specific linting rules for eslint

Installation

npm install eslint eslint-plugin-react --save-dev

It is also possible to install ESLint globally rather than locally (using npm install -g eslint). However, this is not recommended, and any plugins or shareable configs that you use must be installed locally in either case.

Configuration (legacy: .eslintrc*)

Use our preset to get reasonable defaults:

  "extends": [
    "eslint:recommended",
    "plugin:react/recommended"
  ]

If you are using the new JSX transform from React 17, extend react/jsx-runtime in your eslint config (add "plugin:react/jsx-runtime" to "extends") to disable the relevant rules.

You should also specify settings that will be shared across all the plugin rules. (More about eslint shared settings)

{
  "settings": {
    "react": {
      "createClass": "createReactClass", // Regex for Component Factory to use,
                                         // default to "createReactClass"
      "pragma": "React",  // Pragma to use, default to "React"
      "fragment": "Fragment",  // Fragment to use (may be a property of <pragma>), default to "Fragment"
      "version": "detect", // React version. "detect" automatically picks the version you have installed.
                           // You can also use `16.0`, `16.3`, etc, if you want to override the detected value.
                           // Defaults to the "defaultVersion" setting and warns if missing, and to "detect" in the future
      "defaultVersion": "", // Default React version to use when the version you have installed cannot be detected.
                            // If not provided, defaults to the latest React version.
      "flowVersion": "0.53" // Flow version
    },
    "propWrapperFunctions": [
        // The names of any function used to wrap propTypes, e.g. `forbidExtraProps`. If this isn't set, any propTypes wrapped in a function will be skipped.
        "forbidExtraProps",
        {"property": "freeze", "object": "Object"},
        {"property": "myFavoriteWrapper"},
        // for rules that check exact prop wrappers
        {"property": "forbidExtraProps", "exact": true}
    ],
    "componentWrapperFunctions": [
        // The name of any function used to wrap components, e.g. Mobx `observer` function. If this isn't set, components wrapped by these functions will be skipped.
        "observer", // `property`
        {"property": "styled"}, // `object` is optional
        {"property": "observer", "object": "Mobx"},
        {"property": "observer", "object": "<pragma>"} // sets `object` to whatever value `settings.react.pragma` is set to
    ],
    "formComponents": [
      // Components used as alternatives to <form> for forms, eg. <Form endpoint={ url } />
      "CustomForm",
      {"name": "SimpleForm", "formAttribute": "endpoint"},
      {"name": "Form", "formAttribute": ["registerEndpoint", "loginEndpoint"]}, // allows specifying multiple properties if necessary
    ],
    "linkComponents": [
      // Components used as alternatives to <a> for linking, eg. <Link to={ url } />
      "Hyperlink",
      {"name": "MyLink", "linkAttribute": "to"},
      {"name": "Link", "linkAttribute": ["to", "href"]}, // allows specifying multiple properties if necessary
    ]
  }
}

If you do not use a preset you will need to specify individual rules and add extra configuration.

Add "react" to the plugins section.

{
  "plugins": [
    "react"
  ]
}

Enable JSX support.

With eslint 2+

{
  "parserOptions": {
    "ecmaFeatures": {
      "jsx": true
    }
  }
}

Enable the rules that you would like to use.

  "rules": {
    "react/jsx-uses-react": "error",
    "react/jsx-uses-vars": "error",
  }

Shareable configs

Recommended

This plugin exports a recommended configuration that enforces React good practices.

To enable this configuration use the extends property in your .eslintrc config file:

{
  "extends": ["eslint:recommended", "plugin:react/recommended"]
}

See eslint documentation for more information about extending configuration files.

All

This plugin also exports an all configuration that includes every available rule. This pairs well with the eslint:all rule.

{
  "plugins": [
    "react"
  ],
  "extends": ["eslint:all", "plugin:react/all"]
}

Note: These configurations will import eslint-plugin-react and enable JSX in parser options.

Configuration (new: eslint.config.js)

From v8.21.0, eslint announced a new config system. In the new system, .eslintrc* is no longer used. eslint.config.js would be the default config file name. In eslint v8, the legacy system (.eslintrc*) would still be supported, while in eslint v9, only the new system would be supported.

And from v8.23.0, eslint CLI starts to look up eslint.config.js. So, if your eslint is >=8.23.0, you're 100% ready to use the new config system.

You might want to check out the official blog posts,

• https://eslint.org/blog/2022/08/new-config-system-part-1/
• https://eslint.org/blog/2022/08/new-config-system-part-2/
• https://eslint.org/blog/2022/08/new-config-system-part-3/

and the official docs.

Plugin

The default export of eslint-plugin-react is a plugin object.

const react = require('eslint-plugin-react');
const globals = require('globals');

module.exports = [
  …
  {
    files: ['**/*.{js,jsx,mjs,cjs,ts,tsx}'],
    plugins: {
      react,
    },
    languageOptions: {
      parserOptions: {
        ecmaFeatures: {
          jsx: true,
        },
      },
      globals: {
        ...globals.browser,
      },
    },
    rules: {
      // ... any rules you want
      'react/jsx-uses-react': 'error',
      'react/jsx-uses-vars': 'error',
     },
    // ... others are omitted for brevity
  },
  …
];

Configuring shared settings

Refer to the official docs.

The schema of the settings.react object would be identical to that of what's already described above in the legacy config section.

Flat Configs

This plugin exports 3 flat configs:

• flat.all
• flat.recommended
• flat['jsx-runtime']

The flat configs are available via the root plugin import. They will configure the plugin under the react/ namespace and enable JSX in languageOptions.parserOptions.

const reactPlugin = require('eslint-plugin-react');

module.exports = [
  …
  reactPlugin.configs.flat.recommended, // This is not a plugin object, but a shareable config object
  reactPlugin.configs.flat['jsx-runtime'], // Add this if you are using React 17+
  …
];

You can of course add/override some properties.

Note: Our shareable configs does not preconfigure files or languageOptions.globals. For most of the cases, you probably want to configure some properties by yourself.

const reactPlugin = require('eslint-plugin-react');
const globals = require('globals');

module.exports = [
  …
  {
    files: ['**/*.{js,mjs,cjs,jsx,mjsx,ts,tsx,mtsx}'],
    ...reactPlugin.configs.flat.recommended,
    languageOptions: {
      ...reactPlugin.configs.flat.recommended.languageOptions,
      globals: {
        ...globals.serviceworker,
        ...globals.browser,
      },
    },
  },
  …
];

The above example is same as the example below, as the new config system is based on chaining.

const reactPlugin = require('eslint-plugin-react');
const globals = require('globals');

module.exports = [
  …
  {
    files: ['**/*.{js,mjs,cjs,jsx,mjsx,ts,tsx,mtsx}'],
    ...reactPlugin.configs.flat.recommended,
  },
  {
    files: ['**/*.{js,mjs,cjs,jsx,mjsx,ts,tsx,mtsx}'],
    languageOptions: {
      globals: {
        ...globals.serviceworker,
        ...globals.browser,
      },
    },
  },
  …
];

List of supported rules

💼 Configurations enabled in.
🚫 Configurations disabled in.
🏃 Set in the jsx-runtime configuration.
☑️ Set in the recommended configuration.
🔧 Automatically fixable by the --fix CLI option.
💡 Manually fixable by editor suggestions.
❌ Deprecated.

Other useful plugins

• Rules of Hooks: eslint-plugin-react-hooks
• JSX accessibility: eslint-plugin-jsx-a11y
• React Native: eslint-plugin-react-native

License

eslint-plugin-react is licensed under the MIT License.