markdown/no-missing-label-refs

[guide] and [the guide][guide] are links only if the document defines guide. If the definition is missing or misspelled, there is no error: the brackets show up in the text.

Configure

Off by default. It needs an ESLint config that says which files are in the language:

import markdown from "@eslint/markdown";

export default [
  {
    files: ["**/*.md"],
    plugins: { markdown },
    language: "markdown/commonmark",
    rules: { "markdown/no-missing-label-refs": "error" },
  },
];

It also works with markdown/gfm.

Examples

Reported:

Read the [guide] and [the reference][ref].

Not reported:

Read the [guide] and [the reference][ref]. \[Not a link\]

[guide]: https://example.com/guide
[ref]: https://example.com/reference

Options

Use it for text in brackets that was never meant to be a link, like GitHub's alerts:

> [!NOTE]
> Restart the server afterwards.