remark-lint
rule to warn when language flags of fenced code
are not used.
- What is this?
- When should I use this?
- Presets
- Install
- Use
- API
- Recommendation
- Examples
- Compatibility
- Contribute
- License
This package checks the language flags of fenced code blocks, whether they exist, and optionally what values they hold.
You can use this package to check that the style of language flags of fenced code blocks is consistent.
This plugin is included in the following presets:
Preset | Options |
---|---|
remark-preset-lint-markdown-style-guide |
{ allowEmpty: false } |
This package is ESM only. In Node.js (version 16+), install with npm:
npm install remark-lint-fenced-code-flag
In Deno with esm.sh
:
import remarkLintFencedCodeFlag from 'https://esm.sh/remark-lint-fenced-code-flag@4'
In browsers with esm.sh
:
<script type="module">
import remarkLintFencedCodeFlag from 'https://esm.sh/remark-lint-fenced-code-flag@4?bundle'
</script>
On the API:
import remarkLint from 'remark-lint'
import remarkLintFencedCodeFlag from 'remark-lint-fenced-code-flag'
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(remarkLintFencedCodeFlag)
.use(remarkStringify)
.process(file)
console.error(reporter(file))
On the CLI:
remark --frail --use remark-lint --use remark-lint-fenced-code-flag .
On the CLI in a config file (here a package.json
):
…
"remarkConfig": {
"plugins": [
…
"remark-lint",
+ "remark-lint-fenced-code-flag",
…
]
}
…
This package exports no identifiers.
It exports the TypeScript type
Options
.
The default export is
remarkLintFencedCodeFlag
.
Warn when language flags of fenced code are not used.
-
options
(Options
orArray<string>
, optional) — configuration or flags to allow
Transform (Transformer
from unified
).
Configuration (TypeScript type).
-
allowEmpty
(boolean
, default:false
) — allow language flags to be omitted -
flags
(Array<string>
, optional) — flags to allow, other flags will result in a warning
While omitting language flags is fine to signal that code is plain text,
it could point to a mistake.
It’s recommended to instead use a certain flag for plain text (such as
txt
) and to turn this rule on.
Some markdown:
```markdown
# Mercury
```
No messages.
```
mercury()
```
1:1-3:4: Unexpected missing fenced code language flag in info string, expected keyword
When configured with { allowEmpty: true }
.
```
mercury()
```
No messages.
When configured with { allowEmpty: false }
.
```
mercury()
```
1:1-3:4: Unexpected missing fenced code language flag in info string, expected keyword
When configured with [ 'markdown' ]
.
```markdown
# Mercury
```
No messages.
When configured with { flags: [ 'markdown' ] }
.
```markdown
# Mercury
```
No messages.
When configured with [ 'markdown' ]
.
```javascript
mercury()
```
1:1-3:4: Unexpected fenced code language flag `javascript` in info string, expected `markdown`
When configured with [ 'javascript', 'markdown', 'mdx', 'typescript' ]
.
```html
<h1>Mercury</h1>
```
1:1-3:4: Unexpected fenced code language flag `html` in info string, expected `javascript`, `markdown`, `mdx`, …
When configured with '🌍'
.
1:1: Unexpected value `🌍` for `options`, expected array or object
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-fenced-code-flag@4
,
compatible with Node.js 16.
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.