remark-lint-no-empty-url

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[remark-lint][github-remark-lint] rule to warn when empty URLs are used.

Contents

* What is this?
* When should I use this?
* Presets
* Install
* Use
* API
* unified().use(remarkLintNoEmptyUrl)
* Recommendation
* Examples
* Compatibility
* Contribute
* License

What is this?

This package checks URLs of definitions, images, and links.

When should I use this?

You can use this package to check that URLs of definitions, images, and
links are not empty.

Presets

This plugin is not included in presets maintained here.

Install

This package is [ESM only][github-gist-esm].
In Node.js (version 16+),
install with [npm][npm-install]:

``sh
npm install remark-lint-no-empty-url
`

In Deno with [esm.sh][esm-sh]:

`js
import remarkLintNoEmptyUrl from 'https://esm.sh/remark-lint-no-empty-url@4'
`

In browsers with [esm.sh][esm-sh]:

`html

`

Use

On the API:

`js
import remarkLint from 'remark-lint'
import remarkLintNoEmptyUrl from 'remark-lint-no-empty-url'
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(remarkLintNoEmptyUrl)
.use(remarkStringify)
.process(file)

console.error(reporter(file))
`

On the CLI:

`sh
remark --frail --use remark-lint --use remark-lint-no-empty-url .
`

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

`diff
…
"remarkConfig": {
"plugins": [
…
"remark-lint",
+ "remark-lint-no-empty-url",
…
]
}
…
`

API

This package exports no identifiers.
It exports no additional [TypeScript][typescript] types.
The default export is
[remarkLintNoEmptyUrl][api-remark-lint-no-empty-url].

$3

Warn when empty URLs are used.

###### Parameters

There are no options.

###### Returns

Transform ([Transformer from unified][github-unified-transformer]).

Recommendation

While it is possible to omit URLs in links and images,
that typically indicates a “placeholder” or something that has to be filled
out later.
It’s recommended to fill them out.

Examples

##### ok.md

###### In

`markdown
Mercury.

!Venus.

[earth]: https://example.com/earth/
`

###### Out

No messages.

##### not-ok.md

###### In

`markdown
[Mercury]().

!Venus.

[earth]: <>
`

###### Out

`text
1:1-1:12: Unexpected empty link URL referencing the current document, expected URL
3:1-3:12: Unexpected empty image URL referencing the current document, expected URL
5:1-5:12: Unexpected empty definition URL referencing the current document, expected URL
`

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-empty-url@4,
compatible with Node.js 16.

Contribute

See [contributing.md][github-dotfiles-contributing] in [remarkjs/.github][github-dotfiles-health] for ways
to get started.
See [support.md`][github-dotfiles-support] for ways to get help.

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

License

[MIT][file-license] © [Titus Wormer][author]

[api-remark-lint-no-empty-url]: #unifieduseremarklintnoemptyurl

[author]: https://wooorm.com

[badge-build-image]: https://github.com/remarkjs/remark-lint/workflows/main/badge.svg

[badge-build-url]: https://github.com/remarkjs/remark-lint/actions

[badge-chat-image]: https://img.shields.io/badge/chat-discussions-success.svg

[badge-chat-url]: https://github.com/remarkjs/remark/discussions

[badge-coverage-image]: https://img.shields.io/codecov/c/github/remarkjs/remark-lint.svg

[badge-coverage-url]: https://codecov.io/github/remarkjs/remark-lint

[badge-downloads-image]: https://img.shields.io/npm/dm/remark-lint-no-empty-url.svg

[badge-downloads-url]: https://www.npmjs.com/package/remark-lint-no-empty-url

[badge-funding-backers-image]: https://opencollective.com/unified/backers/badge.svg

[badge-funding-sponsors-image]: https://opencollective.com/unified/sponsors/badge.svg

[badge-funding-url]: https://opencollective.com/unified

[badge-size-image]: https://img.shields.io/bundlejs/size/remark-lint-no-empty-url

[badge-size-url]: https://bundlejs.com/?q=remark-lint-no-empty-url

[esm-sh]: https://esm.sh

[file-license]: https://github.com/remarkjs/remark-lint/blob/main/license

[github-dotfiles-coc]: https://github.com/remarkjs/.github/blob/main/code-of-conduct.md

[github-dotfiles-contributing]: https://github.com/remarkjs/.github/blob/main/contributing.md

[github-dotfiles-health]: https://github.com/remarkjs/.github

[github-dotfiles-support]: https://github.com/remarkjs/.github/blob/main/support.md

[github-gist-esm]: https://gist.github.com/sindresorhus/a39789f98801d908bbc7ff3ecc99d99c

[github-remark-lint]: https://github.com/remarkjs/remark-lint

[github-unified-transformer]: https://github.com/unifiedjs/unified#transformer

[npm-install]: https://docs.npmjs.com/cli/install

[typescript]: https://www.typescriptlang.org