github-pages-deploy-action/node_modules/eslint-plugin-jsx-a11y/docs/rules/label-has-for.md

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2020-03-07 11:45:40 +08:00
# [Deprecated] label-has-for
*This rule was deprecated in v6.1.0. It will no longer be maintained. Please use [`label-has-associated-control`](label-has-associated-control.md) instead.*
Enforce label tags have associated control.
There are two supported ways to associate a label with a control:
- nesting: by wrapping a control in a label tag
- id: by using the prop `htmlFor` as in `htmlFor=[ID of control]`
To fully cover 100% of assistive devices, you're encouraged to validate for both nesting and id.
## Rule details
This rule takes one optional object argument of type object:
```json
{
"rules": {
"jsx-a11y/label-has-for": [ 2, {
"components": [ "Label" ],
"required": {
"every": [ "nesting", "id" ]
},
"allowChildren": false
}]
}
}
```
For the `components` option, these strings determine which JSX elements (**always including** `<label>`) should be checked for having `htmlFor` prop. This is a good use case when you have a wrapper component that simply renders a `label` element (like in React):
```js
// Label.js
const Label = props => {
const {
htmlFor,
...otherProps
} = props;
return (
<label htmlFor={htmlFor} {...otherProps} />
);
}
...
// CreateAccount.js (for example)
...
return (
<form>
<input id="firstName" type="text" />
<Label htmlFor="firstName">First Name</Label>
</form>
);
```
The `required` option (defaults to `"required": { "every": ["nesting", "id"] }`) determines which checks are activated. You're allowed to pass in one of the following types:
- string: must be one of the acceptable strings (`"nesting"` or `"id"`)
- object, must have one of the following properties:
- some: an array of acceptable strings, will pass if ANY of the requested checks passed
- every: an array of acceptable strings, will pass if ALL of the requested checks passed
The `allowChildren` option (defaults to `false`) determines whether `{children}` content is allowed to be passed into a `label` element. For example, the following pattern, by default, is not allowed:
```js
<label>{children}</label>
```
However, if `allowChildren` is set to `true`, no error will be raised. If you want to pass in `{children}` content without raising an error, because you cannot be sure what `{children}` will render, then set `allowChildren` to `true`.
Note that passing props as spread attribute without `htmlFor` explicitly defined will cause this rule to fail. Explicitly pass down `htmlFor` prop for rule to pass. The prop must have an actual value to pass. Use `Label` component above as a reference. **It is a good thing to explicitly pass props that you expect to be passed for self-documentation.** For example:
#### Bad
```jsx
function Foo(props) {
return <label {...props} />
}
```
#### Good
```jsx
function Foo({ htmlFor, ...props}) {
return <label htmlFor={htmlFor} {...props} />
}
// OR
function Foo(props) {
const {
htmlFor,
...otherProps
} = props;
return <label htmlFor={htmlFor} {...otherProps} />
}
```
### Succeed
```jsx
<label htmlFor="firstName">
<input type="text" id="firstName" />
First Name
</label>
```
### Fail
```jsx
<input type="text" id="firstName" />
<label>First Name</label>
```