remark-lint/packages/remark-lint-file-extension

remark-lint-file-extension

remark-lint rule to warn for unexpected file extensions.

Contents

• What is this?
• When should I use this?
• Presets
• Install
• Use
• API
  • unified().use(remarkLintFileExtension[, options])
• Recommendation
• Examples
• Compatibility
• Contribute
• License

What is this?

This package checks the file extension.

When should I use this?

You can use this package to check that file extensions are consistent.

Presets

This plugin is included in the following presets:

Preset	Options
remark-preset-lint-markdown-style-guide	'md'

Install

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

npm install remark-lint-file-extension

In Deno with esm.sh:

import remarkLintFileExtension from 'https://esm.sh/remark-lint-file-extension@2'

In browsers with esm.sh:

<script type="module">
  import remarkLintFileExtension from 'https://esm.sh/remark-lint-file-extension@2?bundle'
</script>

Use

On the API:

import remarkLint from 'remark-lint'
import remarkLintFileExtension from 'remark-lint-file-extension'
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(remarkLintFileExtension)
  .use(remarkStringify)
  .process(file)

console.error(reporter(file))

On the CLI:

remark --frail --use remark-lint --use remark-lint-file-extension .

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

 …
 "remarkConfig": {
   "plugins": [
     …
     "remark-lint",
+    "remark-lint-file-extension",
     …
   ]
 }
 …

API

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

unified().use(remarkLintFileExtension[, options])

Warn for unexpected extensions.

👉 Note: does not warn when files have no file extensions (such as AUTHORS or LICENSE).

Parameters

• options (string, default: 'md') — preferred file extension

Returns

Transform (Transformer from unified).

Recommendation

Use md as it’s the most common. Also use md when your markdown contains common syntax extensions (such as GFM, frontmatter, or math). Do not use md for MDX: use mdx instead.

Examples

readme.md

Out

No messages.

readme

Out

No messages.

readme.mkd

Out

1:1: Incorrect extension: use `md`

readme.mkd

When configured with 'mkd'.

Out

No messages.

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-file-extension@2, compatible with Node.js 12.

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