rustdoc does not warn about misuse of html render option attributes

[lolbinarycat]

Code

#![doc(html_favicon_url)]
#![doc(html_logo_url)]
#![doc(html_playground_url)]
#![doc(issue_tracker_base_url)]
#![doc(html_no_source = "asdf")]

Expected Outcome

Rustdoc should emit a separate warning or error for each attribute misuse.

I would recommend a new lint (eg. rustdoc::bad_render_attr), which would be introduced as warn by default, then upgraded to deny by default, and eventually made a hard error over an edition.

Actual Output

All attributes are silently ignored.

Version

rustdoc 1.93.0-nightly (53732d5 2025-11-20)

Additional Details

Rustdoc also needs to handle cases like #![doc(html_logo_url = 3)] (mismatched type instead of missing argument).

[lolbinarycat]

Hmm, this could alternatively just be wrapped into invalid_doc_attributes..

[lolbinarycat]

It would be nice to make it a sub-lint, kinda like broken_intra_doc_links and private_intra_doc_links, tho that relationship is actually defined via control flow and not declarativly..

[lolbinarycat]

Ok, here's another related snippet:

#[doc = 1]
mod foo {}

[lolbinarycat]

Eventually this will all be solved by porting these attributes over to the new parsing infrastructure, but in the meantime I'm gonna try to improve MetaItemInner's ABI. hopefully changing semantics and implementation separately will make for a smoother transition, since then we should be able to have the rewrite's behavior be identical to what we were doing before.

[lolbinarycat]

yet another thing we don't catch: duplicate attributes (i think there's already an issue for this)