FormidableLabs/eslint-plugin-react-native-a11y

Eslint-plugin-react-native-a11y is a collection of React Native specific ESLint rules for identifying accessibility issues. Building upon the foundation set down by eslint-plugin-jsx-a11y, eslint-plugin-react-native-a11y detects a few of the most commonly made accessibility issues found in react native apps. These rules make it easier for your apps to be navigable by users with screen readers.

Setup

Pre-Requisites

Before starting, check you already have ESLint as a devDependency of your project.

Projects created using react-native init will already have this, but for Expo depending on your template you may need to follow ESLint's installation instructions.

Installation

Next, install eslint-plugin-react-native-a11y:

npm install eslint-plugin-react-native-a11y --save-dev

# or

yarn add eslint-plugin-react-native-a11y --dev

Note: If you installed ESLint globally (using the -g flag in npm, or the global prefix in yarn) then you must also install eslint-plugin-react-native-a11y globally.

Configuration

This plugin exposes four recommended configs.

If your project only supports a single platform, you may get the best experience using a platform-specific config. This will both avoid reporting issues which do not affect your platform and also results in slightly faster linting for larger projects.

If you are unsure which one to use, in most cases all can be safely used.

Add the config you want to use to the extends section of your ESLint config using the pattern plugin:react-native-a11y/ followed by your config name, as shown below:

// .eslintrc.js

module.exports = {
  root: true,
  extends: [
    '@react-native-community',
    'plugin:react-native-a11y/ios'
  ]
};

Alternatively if you do not want to use one of the pre-defined configs — or want to override the behaviour of a specific rule — you can always include a list rules and configurations in the rules section of your ESLint config.

// .eslintrc.js

module.exports = {
  root: true,
  extends: [
    '@react-native-community',
  ],
  rules: {
    'react-native-a11y/rule-name': 2
  }
};

For more information on configuring behaviour of an individual rule, please refer to the ESLint docs

Supported Rules

Basic

• has-accessibility-hint: Enforce accessibilityHint is used in conjunction with accessibilityLabel
• has-accessibility-props: Enforce that <Touchable\*> components only have either the accessibilityRole prop or both accessibilityTraits and accessibilityComponentType props set
• has-valid-accessibility-actions: Enforce both accessibilityActions and onAccessibilityAction props are valid
• has-valid-accessibility-role: Enforce accessibilityRole property value is valid
• has-valid-accessibility-state: Enforce accessibilityState property value is valid
• has-valid-accessibility-states: Enforce accessibilityStates property value is valid
• has-valid-accessibility-component-type: Enforce accessibilityComponentType property value is valid
• has-valid-accessibility-traits: Enforce accessibilityTraits and accessibilityComponentType prop values must be valid
• has-valid-accessibility-value: Enforce accessibilityValue property value is valid
• no-nested-touchables: Enforce if a view has accessible={true}, that there are no touchable elements inside
• has-valid-accessibility-descriptors: Ensures that Touchable* components have appropriate props to communicate with assistive technologies

iOS

• has-valid-accessibility-ignores-invert-colors: Enforce that certain elements use accessibilityIgnoresInvertColors to avoid being inverted by device color settings.

Android

• has-valid-accessibility-live-region: Enforce accessibilityLiveRegion prop values must be valid
• has-valid-important-for-accessibility: Enforce importantForAccessibility property value is valid

Rule Options

The following options are available to customize the recommended rule set.

Custom Touchables

react-native-a11y/has-accessibility-props and react-native-a11y/no-nested-touchables allow you to define an array of names for custom components that you may have that conform to the same accessibility interfaces as Touchables.

"react-native-a11y/has-accessibility-props": [
  "error",
  {
    "touchables": ["TouchableCustom"]
  }
]

Custom Invertable Components (iOS)

react-native-a11y/has-valid-accessibility-ignores-invert-colors allows you to optionally define an Array of component names to check in addition to <Image />.

For more information, see the rule docs.

"react-native-a11y/has-valid-accessibility-ignores-invert-colors": [
  "error",
  {
    "invertableComponents": [
      "FastImage",
    ]
  }
]

Creating a new rule

If you are developing new rules for this project, you can use the create-rule script to scaffold the new files.

$ ./scripts/create-rule.js my-new-rule

Attribution

This project started as a fork of eslint-plugin-jsx-a11y and a lot of the work was carried out by its contributors, to whom we owe a lot!

License

eslint-plugin-react-native-a11y is licensed under the MIT License.

Maintenance Status

Active: Formidable is actively working on this project, and we expect to continue for work for the foreseeable future. Bug reports, feature requests and pull requests are welcome.