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 eslint --global). However, this is not recommended, and any plugins or shareable configs that you use must be installed locally in either case.

Configuration

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",
  }

List of supported rules

✔: Enabled in the recommended configuration.
🔧: Fixable with eslint --fix.

✔	🔧	Rule	Description
		react/boolean-prop-naming	Enforces consistent naming for boolean props
		react/button-has-type	Forbid "button" element without an explicit "type" attribute
		react/default-props-match-prop-types	Enforce all defaultProps are defined and not "required" in propTypes.
	🔧	react/destructuring-assignment	Enforce consistent usage of destructuring assignment of props, state, and context
✔		react/display-name	Prevent missing displayName in a React component definition
		react/forbid-component-props	Forbid certain props on components
		react/forbid-dom-props	Forbid certain props on DOM Nodes
		react/forbid-elements	Forbid certain elements
		react/forbid-foreign-prop-types	Forbid using another component's propTypes
		react/forbid-prop-types	Forbid certain propTypes
	🔧	react/function-component-definition	Standardize the way function component get defined
		react/hook-use-state	Ensure symmetric naming of useState hook value and setter variables
		react/iframe-missing-sandbox	Enforce sandbox attribute on iframe elements
		react/no-access-state-in-setstate	Reports when this.state is accessed within setState
		react/no-adjacent-inline-elements	Prevent adjacent inline elements not separated by whitespace.
		react/no-array-index-key	Prevent usage of Array index in keys
	🔧	react/no-arrow-function-lifecycle	Lifecycle methods should be methods on the prototype, not class fields
✔		react/no-children-prop	Prevent passing of children as props.
		react/no-danger	Prevent usage of dangerous JSX props
✔		react/no-danger-with-children	Report when a DOM element is using both children and dangerouslySetInnerHTML
✔		react/no-deprecated	Prevent usage of deprecated methods
		react/no-did-mount-set-state	Prevent usage of setState in componentDidMount
		react/no-did-update-set-state	Prevent usage of setState in componentDidUpdate
✔		react/no-direct-mutation-state	Prevent direct mutation of this.state
✔		react/no-find-dom-node	Prevent usage of findDOMNode
	🔧	react/no-invalid-html-attribute	Forbid attribute with an invalid values`
✔		react/no-is-mounted	Prevent usage of isMounted
		react/no-multi-comp	Prevent multiple component definition per file
		react/no-namespace	Enforce that namespaces are not used in React elements
		react/no-redundant-should-component-update	Flag shouldComponentUpdate when extending PureComponent
✔		react/no-render-return-value	Prevent usage of the return value of React.render
		react/no-set-state	Prevent usage of setState
✔		react/no-string-refs	Prevent string definitions for references and prevent referencing this.refs
		react/no-this-in-sfc	Report "this" being used in stateless components
		react/no-typos	Prevent common typos
✔		react/no-unescaped-entities	Detect unescaped HTML entities, which might represent malformed tags
✔	🔧	react/no-unknown-property	Prevent usage of unknown DOM property
		react/no-unsafe	Prevent usage of unsafe lifecycle methods
		react/no-unstable-nested-components	Prevent creating unstable components inside components
		react/no-unused-class-component-methods	Prevent declaring unused methods of component class
		react/no-unused-prop-types	Prevent definitions of unused prop types
		react/no-unused-state	Prevent definition of unused state fields
		react/no-will-update-set-state	Prevent usage of setState in componentWillUpdate
		react/prefer-es6-class	Enforce ES5 or ES6 class for React Components
		react/prefer-exact-props	Prefer exact proptype definitions
	🔧	react/prefer-read-only-props	Require read-only props.
		react/prefer-stateless-function	Enforce stateless components to be written as a pure function
✔		react/prop-types	Prevent missing props validation in a React component definition
✔		react/react-in-jsx-scope	Prevent missing React when using JSX
		react/require-default-props	Enforce a defaultProps definition for every prop that is not a required prop.
		react/require-optimization	Enforce React components to have a shouldComponentUpdate method
✔		react/require-render-return	Enforce ES5 or ES6 class for returning value in render function
	🔧	react/self-closing-comp	Prevent extra closing tags for components without children
		react/sort-comp	Enforce component methods order
		react/sort-prop-types	Enforce propTypes declarations alphabetical sorting
		react/state-in-constructor	State initialization in an ES6 class component should be in a constructor
		react/static-property-placement	Defines where React component static properties should be positioned.
		react/style-prop-object	Enforce style prop value is an object
		react/void-dom-elements-no-children	Prevent passing of children to void DOM elements (e.g. <br />).

JSX-specific rules

✔	🔧	Rule	Description
	🔧	react/jsx-boolean-value	Enforce boolean attributes notation in JSX
		react/jsx-child-element-spacing	Ensures inline tags are not rendered without spaces between them
	🔧	react/jsx-closing-bracket-location	Validate closing bracket location in JSX
	🔧	react/jsx-closing-tag-location	Validate closing tag location for multiline JSX
	🔧	react/jsx-curly-brace-presence	Disallow unnecessary JSX expressions when literals alone are sufficient or enfore JSX expressions on literals in JSX children or attributes
	🔧	react/jsx-curly-newline	Enforce consistent line breaks inside jsx curly
	🔧	react/jsx-curly-spacing	Enforce or disallow spaces inside of curly braces in JSX attributes
	🔧	react/jsx-equals-spacing	Disallow or enforce spaces around equal signs in JSX attributes
		react/jsx-filename-extension	Restrict file extensions that may contain JSX
	🔧	react/jsx-first-prop-new-line	Ensure proper position of the first property in JSX
	🔧	react/jsx-fragments	Enforce shorthand or standard form for React fragments
		react/jsx-handler-names	Enforce event handler naming conventions in JSX
	🔧	react/jsx-indent	Validate JSX indentation
	🔧	react/jsx-indent-props	Validate props indentation in JSX
✔		react/jsx-key	Report missing key props in iterators/collection literals
		react/jsx-max-depth	Validate JSX maximum depth
	🔧	react/jsx-max-props-per-line	Limit maximum of props on a single line in JSX
	🔧	react/jsx-newline	Require or prevent a new line after jsx elements and expressions.
		react/jsx-no-bind	Prevents usage of Function.prototype.bind and arrow functions in React component props
✔		react/jsx-no-comment-textnodes	Comments inside children section of tag should be placed inside braces
		react/jsx-no-constructed-context-values	Prevents JSX context provider values from taking values that will cause needless rerenders.
✔		react/jsx-no-duplicate-props	Enforce no duplicate props
	🔧	react/jsx-no-leaked-render	Prevent problematic leaked values from being rendered
		react/jsx-no-literals	Prevent using string literals in React component definition
		react/jsx-no-script-url	Forbid javascript: URLs
✔	🔧	react/jsx-no-target-blank	Forbid target="_blank" attribute without rel="noreferrer"
✔		react/jsx-no-undef	Disallow undeclared variables in JSX
	🔧	react/jsx-no-useless-fragment	Disallow unnecessary fragments
	🔧	react/jsx-one-expression-per-line	Limit to one expression per line in JSX
		react/jsx-pascal-case	Enforce PascalCase for user-defined JSX components
	🔧	react/jsx-props-no-multi-spaces	Disallow multiple spaces between inline JSX props
		react/jsx-props-no-spreading	Prevent JSX prop spreading
		react/jsx-sort-default-props	Enforce default props alphabetical sorting
	🔧	react/jsx-sort-props	Enforce props alphabetical sorting
	🔧	react/jsx-space-before-closing	Validate spacing before closing bracket in JSX
	🔧	react/jsx-tag-spacing	Validate whitespace in and around the JSX opening and closing brackets
✔		react/jsx-uses-react	Prevent React to be marked as unused
✔		react/jsx-uses-vars	Prevent variables used in JSX to be marked as unused
	🔧	react/jsx-wrap-multilines	Prevent missing parentheses around multilines JSX

Other useful plugins

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

Shareable configurations

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.

License

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