remark-lint rule to warn when headings are too long.
Contents
What is this?
This package checks the length of heading text.
When should I use this?
You can use this package to check that heading text is within reason.
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-maximum-heading-length
In Deno with esm.sh:
import remarkLintMaximumHeadingLength from 'https://esm.sh/remark-lint-maximum-heading-length@4'
In browsers with esm.sh:
<script type="module">
import remarkLintMaximumHeadingLength from 'https://esm.sh/remark-lint-maximum-heading-length@4?bundle'
</script>
Use
On the API:
import remarkLint from 'remark-lint'
import remarkLintMaximumHeadingLength from 'remark-lint-maximum-heading-length'
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(remarkLintMaximumHeadingLength)
.use(remarkStringify)
.process(file)
console.error(reporter(file))
On the CLI:
remark --frail --use remark-lint --use remark-lint-maximum-heading-length .
On the CLI in a config file (here a package.json):
…
"remarkConfig": {
"plugins": [
…
"remark-lint",
+ "remark-lint-maximum-heading-length",
…
]
}
…
API
This package exports no identifiers. It exports the TypeScript type Options. The default export is remarkLintMaximumHeadingLength.
Warn when headings are too long.
Parameters
options (Options or number, optional) — configuration
Returns
Transform (Transformer from unified).
Options
Configuration (TypeScript type).
Properties
size (number, default: 60) — preferred max sizestringLength ((value: string) => number, optional) — function to detect text size
Recommendation
While this rule is sometimes annoying, reasonable size headings do help SEO purposes (bots prefer reasonable headings), visual users (headings are typically displayed quite large), and users of screen readers (who use “jump to heading” features that read every heading out loud to navigate within a page).
To better represent how long headings “look”, you can pass a stringLength function.
Examples
ok.md
In
# Mercury is the first planet from the Sun
Out
No messages.
not-ok.md
When configured with 30.
In
# Mercury is the first planet from the Sun
Out
1:1-1:43: Unexpected `40` characters in heading, expected at most `30` characters
string-length-default.md
When configured with 30.
In
# 水星是太陽系的八大行星中最小和最靠近太陽的行星
Out
No messages.
string-length-custom.md
When configured with { size: 30, stringLength: [Function: stringWidth] }.
In
# 水星是太陽系的八大行星中最小和最靠近太陽的行星
Out
1:1-1:26: Unexpected `46` characters in heading, expected at most `30` characters
mdx.mdx
When configured with 30.
In
👉 Note: this example uses MDX (remark-mdx).
<h1>Mercury is the first planet from the Sun</h1>
Out
1:1-1:50: Unexpected `40` characters in heading, expected at most `30` characters
not-ok.md
When configured with '🌍'.
Out
1:1: Unexpected value `🌍` for `size`, expected `number`
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-maximum-heading-length@4, 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