mdbook

[drahnr]

Is your feature request related to a use-case? Please describe.
recognise mdbook format toml and handle it

Describe the solution you'd like
either a separate project sharing most of the source files or a sub-mode cargo spellcheck mdbook book.toml

Describe alternatives you've considered
There is no alternative that is markdown aware.

[drahnr]

The most relevant part here is detecting language = "en" or whatever is specified for the language key and mapping that to iso languages.
Other than that, we should traverse directories and collect .md / .cmark (?) files recursively.
Building an index of existing files to validate relative urls would be nice too.

[drahnr]

Not really a priority and a bit out of scope.