Add listing of lints (eg via -W help) to rustdoc

[eggyal]

Fixes #83883

r? @jyn514

[jyn514]

Thanks!

[jyn514]

Looks like CI is stuck, but r=me when it's working.

[jyn514]

@bors r+

This is awesome, thank you! Nice job on normalizing the lint names :)

[bors]

📌 Commit 4d23c8e has been approved by jyn514

[camelid]

Hmm, won't it be confusing since a lot of rustc lints won't be run by rustdoc? E.g.,

fn main() {
    [1, 2, 3].into_iter();
}

with rustdoc -W array-into-iter foo.rs prints nothing, while a warning is printed when you run it with rustc.

[jyn514]

@camelid you can still enable those lints with -W lint; if you do that for an unknown lint it gives a hard error:

error[E0602]: unknown lint: `x`
  |
  = note: requested on the command line with `-W x`

I think the list of lints enabled by default is separate, maybe we could just document that somewhere.

[jyn514]

with rustdoc -W array-into-iter foo.rs prints nothing, while a warning is printed when you run it with rustc.

Also, this is an implementation detail of how https://doc.rust-lang.org/nightly/rustdoc/advanced-features.html#cfgdoc-documenting-platform-specific-or-feature-specific-information works, it's not guarenteed.

[camelid]

I think the list of lints enabled by default is separate, maybe we could just document that somewhere.

Yes, but I think it could be confusing that -W array-into-iter silently does nothing.

[jyn514]

Yes, but I think it could be confusing that -W array-into-iter silently does nothing.

That's separate from this change though, I don't think it should block it.