Add --check option for cargo doc

[GuillaumeGomez]

This is a reopening of #8859.

The goal is to allow to run rustdoc --check directly from cargo (which was implemented in rust-lang/rust#78984). And the end goal would be to have rustdoc --check to be run when we use cargo check. For now, it only supports cargo doc --check.

Tracking issue: #10025

[rust-highfive]

r? @Eh2406

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[GuillaumeGomez]

I'm not sure to understand the error. Anyone has an idea what's wrong?

[GuillaumeGomez]

r? @joshtriplett

[ehuss]

There is an issue with openssl 3 (#10013) which will hopefully be fixed soon.

[bors]

☔ The latest upstream changes (presumably #10037) made this pull request unmergeable. Please resolve the merge conflicts.

[jyn514]

I think this should be check --doc, not doc --check. That allows it to be extended to check --doctests and check --all-targets in the future.

[Nemo157]

There would be a little inconsistency between cargo test --doc and cargo check --doc if the latter checks the docs but not the doc-examples.

[Nemo157]

(and for now this can already be used on nightly via cargo rustdoc -- --check -Z unstable-options)

[jyn514]

Sure - maybe it makes sense to hold off on this altogether until we implement rust-lang/rust#41574 ?

[ehuss]

I agree with @jyn514 that I would lean towards having cargo check --doc instead of making this part of the doc command. That would be more consistent with the rest of cargo (there isn't a cargo build --check for example).

[ehuss]

Just checking in to see what the status is here, it's not clear to me if this is waiting on any questions.

[GuillaumeGomez]

I'm not sure either. I think we need to have a discussion before moving forward.

[ehuss]

Closing due to inactivity. I think there is some design work that should probably be agreed upon before continuing here.