@wojtekmaj/eslint-plugin-r

A fork of eslint-plugin-react without the heavy polyfills.

It will rebase and try to release in order to sync with the upstream every day, see .github/workflows/rebase-upstream.yml for details.

Installation

npm install -D eslint-plugin-react@npm:@wojtekmaj/eslint-plugin-r@latest

eslint-plugin-import

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

React specific linting rules for eslint

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.
                           // It will default to "latest" and warn if missing, and to "detect" in the future
      "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": "Form", "formAttribute": "endpoint"}
    ],
    "linkComponents": [
      // Components used as alternatives to <a> for linking, eg. <Link to={ url } />
      "Hyperlink",
      {"name": "Link", "linkAttribute": "to"}
    ]
  }
}

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.

Shareable configs

There're also 3 shareable configs.

• eslint-plugin-react/configs/all
• eslint-plugin-react/configs/recommended
• eslint-plugin-react/configs/jsx-runtime

If your eslint.config.js is ESM, include the .js extension (e.g. eslint-plugin-react/recommended.js). Note that the next semver-major will require omitting the extension for these imports.

Note: These configurations will import eslint-plugin-react and enable JSX in languageOptions.parserOptions.

In the new config system, plugin: protocol(e.g. plugin:react/recommended) is no longer valid. As eslint does not automatically import the preset config (shareable config), you explicitly do it by yourself.

const reactRecommended = require('eslint-plugin-react/configs/recommended');

module.exports = [
  …
  reactRecommended, // This is not a plugin object, but a shareable config object
  …
];

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 reactRecommended = require('eslint-plugin-react/configs/recommended');
const globals = require('globals');

module.exports = [
  …
  {
    files: ['**/*.{js,mjs,cjs,jsx,mjsx,ts,tsx,mtsx}'],
    ...reactRecommended,
    languageOptions: {
      ...reactRecommended.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 reactRecommended = require('eslint-plugin-react/configs/recommended');
const globals = require('globals');

module.exports = [
  …
  {
    files: ['**/*.{js,mjs,cjs,jsx,mjsx,ts,tsx,mtsx}'],
    ...reactRecommended,
  },
  {
    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.

| Name                                 | Description | 💼 | 🚫 | 🔧 | 💡 | ❌ | | :----------------------------------------------------------------------------------------- | :------------------------------------------------------------------------------------------------------------------------------------------- | :- | :- | :- | :- | :- | | boolean-prop-naming | Enforces consistent naming for boolean props | | | | | | | button-has-type | Disallow usage of button elements without an explicit type attribute | | | | | | | default-props-match-prop-types | Enforce all defaultProps have a corresponding non-required PropType | | | | | | | destructuring-assignment | Enforce consistent usage of destructuring assignment of props, state, and context | | | 🔧 | | | | display-name | Disallow missing displayName in a React component definition | ☑️ | | | | | | forbid-component-props | Disallow certain props on components | | | | | | | forbid-dom-props | Disallow certain props on DOM Nodes | | | | | | | forbid-elements | Disallow certain elements | | | | | | | forbid-foreign-prop-types | Disallow using another component's propTypes | | | | | | | forbid-prop-types | Disallow certain propTypes | | | | | | | function-component-definition | Enforce a specific function type for function components | | | 🔧 | | | | hook-use-state | Ensure destructuring and symmetric naming of useState hook value and setter variables | | | | 💡 | | | iframe-missing-sandbox | Enforce sandbox attribute on iframe elements | | | | | | | jsx-boolean-value | Enforce boolean attributes notation in JSX | | | 🔧 | | | | jsx-child-element-spacing | Enforce or disallow spaces inside of curly braces in JSX attributes and expressions | | | | | | | jsx-closing-bracket-location | Enforce closing bracket location in JSX | | | 🔧 | | | | jsx-closing-tag-location | Enforce closing tag location for multiline JSX | | | 🔧 | | | | jsx-curly-brace-presence | Disallow unnecessary JSX expressions when literals alone are sufficient or enforce JSX expressions on literals in JSX children or attributes | | | 🔧 | | | | jsx-curly-newline | Enforce consistent linebreaks in curly braces in JSX attributes and expressions | | | 🔧 | | | | jsx-curly-spacing | Enforce or disallow spaces inside of curly braces in JSX attributes and expressions | | | 🔧 | | | | jsx-equals-spacing | Enforce or disallow spaces around equal signs in JSX attributes | | | 🔧 | | | | jsx-filename-extension | Disallow file extensions that may contain JSX | | | | | | | jsx-first-prop-new-line | Enforce proper position of the first property in JSX | | | 🔧 | | | | jsx-fragments | Enforce shorthand or standard form for React fragments | | | 🔧 | | | | jsx-handler-names | Enforce event handler naming conventions in JSX | | | | | | | jsx-indent | Enforce JSX indentation | | | 🔧 | | | | jsx-indent-props | Enforce props indentation in JSX | | | 🔧 | | | | jsx-key | Disallow missing key props in iterators/collection literals | ☑️ | | | | | | jsx-max-depth | Enforce JSX maximum depth | | | | | | | jsx-max-props-per-line | Enforce maximum of props on a single line in JSX | | | 🔧 | | | | jsx-newline | Require or prevent a new line after jsx elements and expressions. | | | 🔧 | | | | jsx-no-bind | Disallow .bind() or arrow functions in JSX props | | | | | | | jsx-no-comment-textnodes | Disallow comments from being inserted as text nodes | ☑️ | | | | | | jsx-no-constructed-context-values | Disallows JSX context provider values from taking values that will cause needless rerenders | | | | | | | jsx-no-duplicate-props | Disallow duplicate properties in JSX | ☑️ | | | | | | jsx-no-leaked-render | Disallow problematic leaked values from being rendered | | | 🔧 | | | | jsx-no-literals | Disallow usage of string literals in JSX | | | | | | | jsx-no-script-url | Disallow usage of javascript: URLs | | | | | | | jsx-no-target-blank | Disallow target="_blank" attribute without rel="noreferrer" | ☑️ | | 🔧 | | | | jsx-no-undef | Disallow undeclared variables in JSX | ☑️ | | | | | | jsx-no-useless-fragment | Disallow unnecessary fragments | | | 🔧 | | | | jsx-one-expression-per-line | Require one JSX element per line | | | 🔧 | | | | jsx-pascal-case | Enforce PascalCase for user-defined JSX components | | | | | | | jsx-props-no-multi-spaces | Disallow multiple spaces between inline JSX props | | | 🔧 | | | | jsx-props-no-spreading | Disallow JSX prop spreading | | | | | | | jsx-sort-default-props | Enforce defaultProps declarations alphabetical sorting | | | | | ❌ | | jsx-sort-props | Enforce props alphabetical sorting | | | 🔧 | | | | jsx-space-before-closing | Enforce spacing before closing bracket in JSX | | | 🔧 | | ❌ | | jsx-tag-spacing | Enforce whitespace in and around the JSX opening and closing brackets | | | 🔧 | | | | jsx-uses-react | Disallow React to be incorrectly marked as unused | ☑️ | 🏃 | | | | | jsx-uses-vars | Disallow variables used in JSX to be incorrectly marked as unused | ☑️ | | | | | | jsx-wrap-multilines | Disallow missing parentheses around multiline JSX | | | 🔧 | | | | no-access-state-in-setstate | Disallow when this.state is accessed within setState | | | | | | | no-adjacent-inline-elements | Disallow adjacent inline elements not separated by whitespace. | | | | | | | no-array-index-key | Disallow usage of Array index in keys | | | | | | | no-arrow-function-lifecycle | Lifecycle methods should be methods on the prototype, not class fields | | | 🔧 | | | | no-children-prop | Disallow passing of children as props | ☑️ | | | | | | no-danger | Disallow usage of dangerous JSX properties | | | | | | | no-danger-with-children | Disallow when a DOM element is using both children and dangerouslySetInnerHTML | ☑️ | | | | | | no-deprecated | Disallow usage of deprecated methods | ☑️ | | | | | | no-did-mount-set-state | Disallow usage of setState in componentDidMount | | | | | | | no-did-update-set-state | Disallow usage of setState in componentDidUpdate | | | | | | | no-direct-mutation-state | Disallow direct mutation of this.state | ☑️ | | | | | | no-find-dom-node | Disallow usage of findDOMNode | ☑️ | | | | | | no-invalid-html-attribute | Disallow usage of invalid attributes | | | | 💡 | | | no-is-mounted | Disallow usage of isMounted | ☑️ | | | | | | no-multi-comp | Disallow multiple component definition per file | | | | | | | no-namespace | Enforce that namespaces are not used in React elements | | | | | | | no-object-type-as-default-prop | Disallow usage of referential-type variables as default param in functional component | | | | | | | no-redundant-should-component-update | Disallow usage of shouldComponentUpdate when extending React.PureComponent | | | | | | | no-render-return-value | Disallow usage of the return value of ReactDOM.render | ☑️ | | | | | | no-set-state | Disallow usage of setState | | | | | | | no-string-refs | Disallow using string references | ☑️ | | | | | | no-this-in-sfc | Disallow this from being used in stateless functional components | | | | | | | no-typos | Disallow common typos | | | | | | | no-unescaped-entities | Disallow unescaped HTML entities from appearing in markup | ☑️ | | | | | | no-unknown-property | Disallow usage of unknown DOM property | ☑️ | | 🔧 | | | | no-unsafe | Disallow usage of unsafe lifecycle methods | | ☑️ | | | | | no-unstable-nested-components | Disallow creating unstable components inside components | | | | | | | no-unused-class-component-methods | Disallow declaring unused methods of component class | | | | | | | no-unused-prop-types | Disallow definitions of unused propTypes | | | | | | | no-unused-state | Disallow definitions of unused state | | | | | | | no-will-update-set-state | Disallow usage of setState in componentWillUpdate | | | | | | | prefer-es6-class | Enforce ES5 or ES6 class for React Components | | | | | | | prefer-exact-props | Prefer exact proptype definitions | | | | | | | prefer-read-only-props | Enforce that props are read-only | | | 🔧 | | | | prefer-stateless-function | Enforce stateless components to be written as a pure function | | | | | | | prop-types | Disallow missing props validation in a React component definition | ☑️ | | | | | | react-in-jsx-scope | Disallow missing React when using JSX | ☑️ | 🏃 | | | | | require-default-props | Enforce a defaultProps definition for every prop that is not a required prop | | | | | | | require-optimization | Enforce React components to have a shouldComponentUpdate method | | | | | | | require-render-return | Enforce ES5 or ES6 class for returning value in render function | ☑️ | | | | | | self-closing-comp | Disallow extra closing tags for components without children | | | 🔧 | | | | sort-comp | Enforce component methods order | | | | | | | sort-default-props | Enforce defaultProps declarations alphabetical sorting | | | | | | | sort-prop-types | Enforce propTypes declarations alphabetical sorting | | | 🔧 | | | | state-in-constructor | Enforce class component state initialization style | | | | | | | static-property-placement | Enforces where React component static properties should be positioned. | | | | | | | style-prop-object | Enforce style prop value is an object | | | | | | | void-dom-elements-no-children | Disallow void DOM elements (e.g. <img />, <br />) from receiving children | | | | | |

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.