remark-lint rule to warn when undefined definitions are referenced.
Contents
What is this?
This package checks that referenced definitions are defined.
When should I use this?
You can use this package to check for broken references.
Presets
This plugin is included in the following presets:
Install
This package is ESM only. In Node.js (version 16+), install with npm:
npm install remark-lint-no-undefined-references
In Deno with esm.sh:
import remarkLintNoUndefinedReferences from 'https://esm.sh/remark-lint-no-undefined-references@5'
In browsers with esm.sh:
<script type="module">
import remarkLintNoUndefinedReferences from 'https://esm.sh/remark-lint-no-undefined-references@5?bundle'
</script>
Use
On the API:
import remarkLint from 'remark-lint'
import remarkLintNoUndefinedReferences from 'remark-lint-no-undefined-references'
import remarkParse from 'remark-parse'
import remarkStringify from 'remark-stringify'
import {read} from 'to-vfile'
import {unified} from 'unified'
import {reporter} from 'vfile-reporter'
const file = await read('example.md')
await unified()
.use(remarkParse)
.use(remarkLint)
.use(remarkLintNoUndefinedReferences)
.use(remarkStringify)
.process(file)
console.error(reporter(file))
On the CLI:
remark --frail --use remark-lint --use remark-lint-no-undefined-references .
On the CLI in a config file (here a package.json):
…
"remarkConfig": {
"plugins": [
…
"remark-lint",
+ "remark-lint-no-undefined-references",
…
]
}
…
API
This package exports no identifiers. It exports the TypeScript type Options. The default export is remarkLintNoUndefinedReferences.
Warn when undefined definitions are referenced.
Parameters
options (Options, optional) — configuration
Returns
Transform (Transformer from unified).
Options
Configuration (TypeScript type).
Fields
allow (Array<RegExp | string>, optional) — list of values to allow between [ and ]allowShortcutLink (boolean, default: false) — allow shortcut references, which are just brackets such as [text]
Recommendation
Shortcut references use an implicit syntax that could also occur as plain text. To illustrate, it is reasonable to expect an author adding […] to abbreviate some text somewhere in a document:
> Some […] quote.
This isn’t a problem, but it might become one when an author later adds a definition:
Some new text […][].
[…]: #read-more
The second author might expect only their newly added text to form a link, but their changes also result in a link for the text by the first author.
Examples
ok.md
In
[Mercury][] is the first planet from the Sun and the smallest in the Solar
System.
Venus is the second planet from the [Sun.
Earth is the third planet from the \[Sun] and the only astronomical object
known to harbor life\.
Mars is the fourth planet from the Sun: [].
[mercury]: https://example.com/mercury/
Out
No messages.
not-ok.md
In
[Mercury] is the first planet from the Sun and the smallest in the Solar
System.
[Venus][] is the second planet from the Sun.
[Earth][earth] is the third planet from the Sun and the only astronomical
object known to harbor life.
![Mars] is the fourth planet from the Sun in the [Solar
System].
> Jupiter is the fifth planet from the Sun and the largest in the [Solar
> System][].
[Saturn][ is the sixth planet from the Sun and the second-largest
in the Solar System, after Jupiter.
[*Uranus*][] is the seventh planet from the Sun.
[Neptune][neptune][more] is the eighth and farthest planet from the Sun.
Out
1:1-1:10: Unexpected reference to undefined definition, expected corresponding definition (`mercury`) for a link or escaped opening bracket (`\[`) for regular text
4:1-4:10: Unexpected reference to undefined definition, expected corresponding definition (`venus`) for a link or escaped opening bracket (`\[`) for regular text
6:1-6:15: Unexpected reference to undefined definition, expected corresponding definition (`earth`) for a link or escaped opening bracket (`\[`) for regular text
9:2-9:8: Unexpected reference to undefined definition, expected corresponding definition (`mars`) for an image or escaped opening bracket (`\[`) for regular text
9:50-10:8: Unexpected reference to undefined definition, expected corresponding definition (`solar system`) for a link or escaped opening bracket (`\[`) for regular text
12:67-13:12: Unexpected reference to undefined definition, expected corresponding definition (`solar > system`) for a link or escaped opening bracket (`\[`) for regular text
15:1-15:9: Unexpected reference to undefined definition, expected corresponding definition (`saturn`) for a link or escaped opening bracket (`\[`) for regular text
18:1-18:13: Unexpected reference to undefined definition, expected corresponding definition (`*uranus*`) for a link or escaped opening bracket (`\[`) for regular text
20:1-20:19: Unexpected reference to undefined definition, expected corresponding definition (`neptune`) for a link or escaped opening bracket (`\[`) for regular text
20:19-20:25: Unexpected reference to undefined definition, expected corresponding definition (`more`) for a link or escaped opening bracket (`\[`) for regular text
ok-allow.md
When configured with { allow: [ '…' ] }.
In
Mercury is the first planet from the Sun and the smallest in the Solar
System. […]
Out
No messages.
source.md
When configured with { allow: [ { source: '^mer' }, 'venus' ] }.
In
[Mercury][] is the first planet from the Sun and the smallest in the Solar
System.
[Venus][] is the second planet from the Sun.
Out
No messages.
gfm.md
In
👉 Note: this example uses GFM (remark-gfm).
Mercury[^mercury] is the first planet from the Sun and the smallest in the
Solar System.
[^venus]:
**Venus** is the second planet from the Sun.
Out
1:8-1:18: Unexpected reference to undefined definition, expected corresponding definition (`mercury`) for a footnote or escaped opening bracket (`\[`) for regular text
allow-shortcut-link.md
When configured with { allowShortcutLink: true }.
In
[Mercury] is the first planet from the Sun and the smallest in the Solar
System.
[Venus][] is the second planet from the Sun.
[Earth][earth] is the third planet from the Sun and the only astronomical object
known to harbor life.
Out
4:1-4:10: Unexpected reference to undefined definition, expected corresponding definition (`venus`) for a link or escaped opening bracket (`\[`) for regular text
6:1-6:15: Unexpected reference to undefined definition, expected corresponding definition (`earth`) for a link or escaped opening bracket (`\[`) for regular text
Compatibility
Projects maintained by the unified collective are compatible with maintained versions of Node.js.
When we cut a new major release, we drop support for unmaintained versions of Node. This means we try to keep the current release line, remark-lint-no-undefined-references@5, compatible with Node.js 16.
Contribute
See contributing.md in remarkjs/.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