Remark-lint-no-duplicate-defined-urls NPM

remark-lint-no-duplicate-defined-urls

remark-lint rule to warn when URLs are defined multiple times.

What is this?

This package checks that defined URLs are unique.

When should I use this?

You can use this package to check that definitions are useful.

Presets

This plugin is not included in presets maintained here.

Install

This package is ESM only. In Node.js (version 16+), install with npm:

npm install remark-lint-no-duplicate-defined-urls

In Deno with esm.sh:

import remarkLintNoDuplicateDefinedUrls from 'https://esm.sh/remark-lint-no-duplicate-defined-urls@3'

In browsers with esm.sh:

<script type="module">
  import remarkLintNoDuplicateDefinedUrls from 'https://esm.sh/remark-lint-no-duplicate-defined-urls@3?bundle'
</script>

Use

On the API:

import remarkLint from 'remark-lint'
import remarkLintNoDuplicateDefinedUrls from 'remark-lint-no-duplicate-defined-urls'
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(remarkLintNoDuplicateDefinedUrls)
  .use(remarkStringify)
  .process(file)

console.error(reporter(file))

On the CLI:

remark --frail --use remark-lint --use remark-lint-no-duplicate-defined-urls .

On the CLI in a config file (here a package.json):

 …
 "remarkConfig": {
   "plugins": [
     …
     "remark-lint",
+    "remark-lint-no-duplicate-defined-urls",
     …
   ]
 }
 …

API

This package exports no identifiers. It exports no additional TypeScript types. The default export is remarkLintNoDuplicateDefinedUrls.

`unified().use(remarkLintNoDuplicateDefinedUrls)`

Warn when URLs are defined multiple times.

Parameters

There are no options.

Returns

Transform (Transformer from unified).

Recommendation

It’s likely a mistake when the same URL is defined with different identifiers.

Examples

`ok.md`

In

The first planet is [mercury][].

[mercury]: https://example.com/mercury/
[venus]: https://example.com/venus/

Out

No messages.

`not-ok.md`

In

[mercury]: https://example.com/mercury/
[venus]: https://example.com/mercury/

Out

2:1-2:38: Unexpected definition with an already defined URL (as `mercury`), expected unique URLs

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-duplicate-defined-urls@3, compatible with Node.js 16.