rehype-code-titles

Rehype plugin for parsing code blocks and adding titles to code blocks

Why?

I moved my blog over to using mdx-bundler which uses xdm under the hood to parse the markdown and MDX files. I was using remark-code-titles prior to this move and unfortunately it no longer worked. I believe this was because of the order plugins were being applied internally for xdm. I'd never really worked with remark or rehype directly before and didn't have a lot of experience with ASTs so this was a fun little project that I initially built directly into my blog before pulling it out at a plugin to ship to other developers.

Many thanks to @mottox2, @mapbox, & @wooorm for their prior work in this ecosystem it was of great help when creating this plugin.

Installation

This package is ESM only: Node 16+ is needed to use it and it must be imported instead of required.

npm install rehype-code-titles

yarn add rehype-code-titles

pnpm add rehype-code-titles

bun add rehype-code-titles

Node.js Support

This plugin supports Node.js 16+, tested on Node 16, 18, 20, and 22.

⚠️ Note: Node 16 reached End-of-Life in September 2023 and no longer receives security updates. We recommend upgrading to Node 18 or 20 (Active LTS) for security and performance improvements.

• Minimum: Node.js 16+ (⚠️ EOL)
• Recommended: Node.js 18+ or 20+ (Active LTS)
• Tested: Node.js 16, 18, 20, 22

API

This package exports no identifiers. The default export is rehypeCodeTitles

rehype().use(rehypeCodeTitles[, options])

Add support for stripping out code titles from input.

options

options.customClassName

Specify your own custom css class name to apply. Defaults to rehype-code-title. Note: you will have to write the CSS implementation yourself.

For example

// some global css file
.rehype-code-title {
  margin-bottom: -0.6rem;
  padding: 0.5em 1em;
  font-family:
    Consolas, "Andale Mono WT", "Andale Mono", "Lucida Console",
    "Lucida Sans Typewriter", "DejaVu Sans Mono", "Bitstream Vera Sans Mono",
    "Liberation Mono", "Nimbus Mono L", Monaco, "Courier New", Courier,
    monospace;

  background-color: black;
  color: white;
  z-index: 0;

  border-top-left-radius: 0.3em;
  border-top-right-radius: 0.3em;
}

options.titleSeparator

Specify the title separator for rehype-code-title. Defaults to: :.

// default behavior will be
"language-typescript:lib/mdx.ts"; // the title will be lib/mdx.ts
"language-typescript:title=lib/mdx.ts"; // title will be title=lib/mdx.ts

// titleSeparator set to :title=
"language-typescript:lib/mdx.ts"; // Wont work! 😱. Does not match the separator
"language-typescript:title=lib/mdx.ts"; // title will be lib/mdx.ts

Input

## Code Example

```typescript:lib/mdx.ts
// code here
```

Output

<div class="rehype-code-title">lib/mdx.ts</div>
<pre>
  <code class="language-typescript">
  <!-- HTML parse code here -->
  </code>
</pre>

Usage

Use this package as a rehype plugin.

const rehype = require("rehype");
const rehypeCodeTitles = require("rehype-code-titles");
const rehypePrism = require("@mapbox/rehype-prism");

rehype()
  .use(rehypeCodeTitles) // should always be before rehypePrism.
  .use(rehypePrism)
  .process(/* some html */);

const unified = require("unified");
const rehypeParse = require("rehype-parse");
const rehypeCodeTitles = require("rehype-code-titles");
const rehypePrism = require("@mapbox/rehype-prism");

unified()
  .use(rehypeParse)
  .use(rehypeCodeTitles)
  .use(rehypePrism)
  .processSync(/* some html */);

Development

This repository uses Bun for package management and testing.

git clone https://github.com/rockchalkwushock/rehype-code-titles.git
cd rehype-code-titles
bun install
# Do cool stuff with code
bun test        # Run tests
bun run lint    # Run linter
bun run build   # Build the package
git add .
git commit -m "feat(src): a cool new feature"
git push

Contributing

Please visit CONTRIBUTING.md

License

MIT © Cody Brunner

Contributors ✨

Thanks goes to these wonderful people (emoji key):

Cody Brunner 💻 📖 ⚠️

Taran Bains

This project follows the all-contributors specification. Contributions of any kind welcome!