mdast-util-gfm-autolink-literal

mdast extensions to parse and serialize GFM autolinks.

Contents

• What is this?
• When to use this
• Install
• Use
• API
  • gfmAutolinkLiteralFromMarkdown
  • gfmAutolinkLiteralToMarkdown
• Syntax tree
• Types
• Compatibility
• Related
• Contribute
• License

What is this?

This package contains extensions that add support for the autolink syntax enabled by GFM to mdast-util-from-markdown and mdast-util-to-markdown.

GitHub employs different algorithms to autolink: one at parse time and one at transform time (similar to how @mentions are done at transform time). This difference can be observed because character references and escapes are handled differently. But also because issues/PRs/comments omit (perhaps by accident?) the second algorithm for www., http://, and https:// links (but not for email links).

As the corresponding micromark extension micromark-extension-gfm-autolink-literal is a syntax extension, it can only perform the first algorithm. The tree extension gfmAutolinkLiteralFromMarkdown from this package can perform the second algorithm, and as they are combined, both are done.

When to use this

These tools are all rather low-level. In most cases, you’d want to use remark-gfm with remark instead.

When you are working with syntax trees and want all of GFM, use mdast-util-gfm instead.

When working with mdast-util-from-markdown, you must combine this package with micromark-extension-gfm-autolink-literal.

This utility does not handle how markdown is turned to HTML. That’s done by mdast-util-to-hast.

Install

This package is ESM only. In Node.js (version 12.20+, 14.14+, or 16.0+), install with npm:

npm install mdast-util-gfm-autolink-literal

In Deno with esm.sh:

import {gfmAutolinkLiteralFromMarkdown, gfmAutolinkLiteralToMarkdown} from 'https://esm.sh/mdast-util-gfm-autolink-literal@1'

In browsers with esm.sh:

<script type="module">
  import {gfmAutolinkLiteralFromMarkdown, gfmAutolinkLiteralToMarkdown} from 'https://esm.sh/mdast-util-gfm-autolink-literal@1?bundle'
</script>

Use

Say our document example.md contains:

www.example.com, https://example.com, and contact@example.com.

…and our module example.js looks as follows:

import fs from 'node:fs/promises'
import {fromMarkdown} from 'mdast-util-from-markdown'
import {toMarkdown} from 'mdast-util-to-markdown'
import {gfmAutolinkLiteral} from 'micromark-extension-gfm-autolink-literal'
import {gfmAutolinkLiteralFromMarkdown, gfmAutolinkLiteralToMarkdown} from 'mdast-util-gfm-autolink-literal'

const doc = await fs.readFile('example.md')

const tree = fromMarkdown(doc, {
  extensions: [gfmAutolinkLiteral],
  mdastExtensions: [gfmAutolinkLiteralFromMarkdown]
})

console.log(tree)

const out = toMarkdown(tree, {extensions: [gfmAutolinkLiteralToMarkdown]})

console.log(out)

…now running node example.js yields (positional info removed for brevity):

{
  type: 'root',
  children: [
    {
      type: 'paragraph',
      children: [
        {
          type: 'link',
          title: null,
          url: 'http://www.example.com',
          children: [{type: 'text', value: 'www.example.com'}]
        },
        {type: 'text', value: ', '},
        {
          type: 'link',
          title: null,
          url: 'https://example.com',
          children: [{type: 'text', value: 'https://example.com'}]
        },
        {type: 'text', value: ', and '},
        {
          type: 'link',
          title: null,
          url: 'mailto:contact@example.com',
          children: [{type: 'text', value: 'contact@example.com'}]
        },
        {type: 'text', value: '.'}
      ]
    }
  ]
}

[www.example.com](http://www.example.com), <https://example.com>, and <contact@example.com>.

API

This package exports the identifiers gfmAutolinkLiteralFromMarkdown and gfmAutolinkLiteralToMarkdown. There is no default export.

gfmAutolinkLiteralFromMarkdown

Extension for mdast-util-from-markdown.

gfmAutolinkLiteralToMarkdown

Extension for mdast-util-to-markdown.

Syntax tree

There are no interfaces added to mdast by this utility, as it reuses the existing Link interface.

Types

This package is fully typed with TypeScript. It does not export additional types.

The Link node type is supported in @types/mdast by default.

Compatibility

Projects maintained by the unified collective are compatible with all maintained versions of Node.js. As of now, that is Node.js 12.20+, 14.14+, and 16.0+. Our projects sometimes work with older versions, but this is not guaranteed.

This plugin works with mdast-util-from-markdown version 1+ and mdast-util-to-markdown version 1+.

Related

• remarkjs/remark-gfm — remark plugin to support GFM
• syntax-tree/mdast-util-gfm — same but all of GFM (autolink literals, footnotes, strikethrough, tables, tasklists)
• micromark/micromark-extension-gfm-autolink-literal — micromark extension to parse GFM autolink literals

Contribute

See contributing.md in syntax-tree/.github for ways to get started. See support.md for ways to get help.

This project has a code of conduct. By interacting with this repository, organization, or community you agree to abide by its terms.

License

MIT © Titus Wormer