Enable the use of alternate fonts in cargo doc.

[arj0019]

Problem

I would like to utilize alternate fonts with cargo doc. I specifically seek the ability to utilize monospace fonts.

Proposed Solution

Allow the user to configure cargo doc via the command line and/or configuration file.

Notes

No response

[weihanglo]

rustdoc provides a couple of flags letting you customize CSS:

• --markdown-css
• -e/--extend-css
• Many other HTML related flags

You can combine them with Cargo's config value build.rustdocflags or command cargo rustdoc to get what you want.

[weihanglo]

Cargo does promote flags from rustc/rustdoc to become first-class flags of Cargo itself, such as cargo doc --document-private-items (#1520). However, for this case I feel like it is not that frequent to tweak style via command line. It should be more common to set up a configuration for styling once and for all.

As a result, I am going to close this given the alternatives are obvious. Thank you!

[arj0019]

I am able to implement the cargo config file, but it does not recognize the --markdown-css flag and there is no example of interfacing with the rustdoc CSS.

PS C:\Users\johnsoar\Documents\Personal\GITHUB\charts> cargo doc
 Documenting charts v0.1.0 (C:\Users\johnsoar\Documents\Personal\GITHUB\charts)
error: Unrecognized option: 'markdown-css docstyle.css'

error: could not document `charts`

Caused by:
  process didn't exit successfully: `rustdoc --edition=2021 --crate-type lib --crate-name charts src\lib.rs -o C:\Users\johnsoar\Documents\Personal\GITHUB\charts\target\doc --error-format=json --json=diagnostic-rendered-ansi,artifacts,future-incompat -C metadata=8b232a5edf7611e6 -L dependency=C:\Users\johnsoar\Documents\Personal\GITHU
B\charts\target\debug\deps "--markdown-css docstyle.css" --crate-version 0.1.0` (exit code: 1)

[weihanglo]

Your arguments are merged into one "--markdown-css docstyle.css". If you're using Cargo configuration, try using array, like rustdocflags = ["--markdown-css", "docstyle.css"].

[arj0019]

Is there documentation of how to implement custom CSS for rustdoc? Where is the default CSS located?

[weihanglo]

Links above #11530 (comment) are probably enough to play with.

There is also an old article from an official rustdoc team member talking about unstable --extend-css stuff (now stabilized).

I guess the default CSS is embedded in the rustdoc source code and generated on-the-fly, though I am not familiar with rustdoc internals.

Hope these help :)