# remark-autolink-headings
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[**remark**][remark] plugin to automatically add links to headings.
> This package integrates with [`remark-html`][remark-html] (or alternatives).
> It is better to work with [**rehype**][rehype], which is specifically made
> for HTML, and to use [`rehype-autolink-headings`][rehype-autolink-headings]
> instead of this package.
> This package works with headings that have IDs.
> One way to add IDs to headings is by using [`remark-slug`][remark-slug] before
> this plugin.
## Note!
This plugin is ready for the new parser in remark
([`remarkjs/remark#536`](https://github.com/remarkjs/remark/pull/536)).
No change is needed: it works exactly the same now as it did before!
## Install
[npm][]:
```sh
npm install remark-autolink-headings
```
## Use
Say we have the following markdown file, `example.md`:
```markdown
# Lorem ipsum 😪
## dolor—sit—amet
### consectetur & adipisicing
#### elit
##### elit
```
And our script, `example.js`, looks as follows:
```js
const fs = require('fs')
const unified = require('unified')
const markdown = require('remark-parse')
const html = require('remark-html')
const slug = require('remark-slug')
const headings = require('remark-autolink-headings')
const doc = unified()
.use(markdown)
.use(slug)
// Note that this module must be included after `remark-slug`.
.use(headings)
.use(html)
.processSync(fs.readFileSync('example.md'))
.toString()
console.log(doc)
```
Now, running `node example` yields:
```html
Lorem ipsum 😪
dolor—sit—amet
consectetur & adipisicing
elit
elit
```
## API
### `remark().use(autolinkHeadings[, options])`
Automatically add links to headings.
##### `options`
###### `options.behavior`
How to create links (`string`, default: `'prepend'`).
* `'prepend'` — inject link before the heading text
* `'append'` — inject link after the heading text
* `'wrap'` — wrap the whole heading text with the link
* `'before'` — insert link before the heading
* `'after'` — insert link after the heading
Supplying `wrap` will ignore any value defined by the `content` option.
Supplying `prepend`, `append`, or `wrap` will ignore the `group` option.
###### `options.linkProperties`
Extra properties to set on the link (`Object?`).
Defaults to `{ariaHidden: 'true', tabIndex: -1}` when in `'prepend'` or `'append'`
mode.
###### `options.content`
[**hast**][hast] nodes to insert in the link (`Function|Node|Children`).
By default, the following is used:
```js
{
type: 'element',
tagName: 'span',
properties: {className: ['icon', 'icon-link']}
}
```
If `behavior` is `wrap`, then `content` is ignored.
If `content` is a function, it’s called with the current heading (`Node`) and
should return one or more nodes:
```js
const toString = require('mdast-util-to-string')
const h = require('hastscript')
// …
function content(node) {
return [
h('span.visually-hidden', 'Read the “', toString(node), '” section'),
h('span.icon.icon-link', {ariaHidden: 'true'})
]
}
```
###### `options.group`
[**hast**][hast] node to wrap the heading and link with (`Function|Node`), if
`behavior` is `before` or `after`.
There is no default.
If `behavior` is `prepend`, `append`, or `wrap`, then `group` is ignored.
If `group` is a function, it’s called with the current heading (`Node`) and
should return a hast node.
```js
const h = require('hastscript')
// …
function group(node) {
return h('div.heading-' + node.depth + '-group')
}
```
## Security
Use of `remark-autolink-headings` can open you up to a
[cross-site scripting (XSS)][xss] attack if you pass user provided content in
`linkProperties` or `content`.
Always be wary of user input and use [`rehype-sanitize`][sanitize].
## Contribute
See [`contributing.md`][contributing] in [`remarkjs/.github`][health] for ways
to get started.
See [`support.md`][support] for ways to get help.
This project has a [code of conduct][coc].
By interacting with this repository, organization, or community you agree to
abide by its terms.
## License
[MIT][license] © [Ben Briggs][author]
[build-badge]: https://github.com/remarkjs/remark-autolink-headings/workflows/main/badge.svg
[build]: https://github.com/remarkjs/remark-autolink-headings/actions
[coverage-badge]: https://img.shields.io/codecov/c/github/remarkjs/remark-autolink-headings.svg
[coverage]: https://codecov.io/github/remarkjs/remark-autolink-headings
[downloads-badge]: https://img.shields.io/npm/dm/remark-autolink-headings.svg
[downloads]: https://www.npmjs.com/package/remark-autolink-headings
[size-badge]: https://img.shields.io/bundlephobia/minzip/remark-autolink-headings.svg
[size]: https://bundlephobia.com/result?p=remark-autolink-headings
[sponsors-badge]: https://opencollective.com/unified/sponsors/badge.svg
[backers-badge]: https://opencollective.com/unified/backers/badge.svg
[collective]: https://opencollective.com/unified
[chat-badge]: https://img.shields.io/badge/chat-discussions-success.svg
[chat]: https://github.com/remarkjs/remark/discussions
[npm]: https://docs.npmjs.com/cli/install
[health]: https://github.com/remarkjs/.github
[contributing]: https://github.com/remarkjs/.github/blob/HEAD/contributing.md
[support]: https://github.com/remarkjs/.github/blob/HEAD/support.md
[coc]: https://github.com/remarkjs/.github/blob/HEAD/code-of-conduct.md
[license]: license
[author]: http://beneb.info
[remark]: https://github.com/remarkjs/remark
[remark-slug]: https://github.com/remarkjs/remark-slug
[remark-html]: https://github.com/remarkjs/remark-html
[rehype]: https://github.com/rehypejs/rehype
[rehype-autolink-headings]: https://github.com/rehypejs/rehype-autolink-headings
[hast]: https://github.com/syntax-tree/hast
[xss]: https://en.wikipedia.org/wiki/Cross-site_scripting
[sanitize]: https://github.com/rehypejs/rehype-sanitize