Highlight lines of included file with docgen

[wiebekaai]

https://fumadocs.vercel.app/docs/headless/mdx/remark-docgen

Hey, any way I can highlight lines when including a file as code block? Or even better, only include certain lines?

[fuma-nama]

We use Shiki for code highlighting, you can use transformers inside your code: https://fumadocs.vercel.app/docs/ui/markdown#highlight-lines

[wiebekaai]

Thanks! I don't understand how to use it with docgen though. Here's what I tried:

```json doc-gen:file
{
  "file": "../snippets/assets.liquid",
  "codeblock": {
    "lang": "liquid",
    "meta": "title=\"snippets/assets.liquid\" custom=\"{1}\" "
  }
}```

```json doc-gen:file
{
  "file": "../snippets/assets.liquid",
  "codeblock": {
    "lang": "liquid",
    "meta": "title=\"snippets/assets.liquid\" {1}"
  }
}```

[fuma-nama]

I mean adding the comment like:

// [!code highlight]

To your code. This is called notation transformers in Shiki

[wiebekaai]

Ah, that makes sense. I tried using actual project code in the docs, but these comments break the code (.liquid files). Guess that's just not a good idea.

Thank you.

[fuma-nama]

I see, if your code isn't supported by notation transformers, you can use meta highlight instead. You can just pass it as meta string similar to your code above.

This transformer isn't installed by default, so you might have to install the shiki/transformers package and add the transformer yourself.
Maybe I can open a PR to Shiki to fix this later