rustdoc: Tracking issue for normalizing (evaluating) types in rustdoc-generated docs (`-Z normalize-docs`)

[jyn514]

This is a tracking issue for the rustdoc feature -Z normalize-docs. This normalizes projections like <Vec<T> as IntoIterator>::IntoIter to std::vec::IntoIter<T> in the generated documentation.

Note

Tracking issues are used to record the overall progress of implementation.
They are also used as hubs connecting to other relevant issues, e.g., bugs or open design questions.

A tracking issue is however not meant for large scale discussion, questions, or bug reports.
Instead, open a dedicated issue for the specific matter or post in the #t-rustdoc Zulip channel.

Discussion comments will get marked as off-topic or deleted.
Repeated discussions on the tracking issue may lead to the tracking issue getting locked.

Steps

• Implement the features (Normalize <X as Y>::T for rustdoc #77467)
• Fix the bugs blocking stabilization (Move reporting recursion limit errors outside of the trait system #81091)
  • Cycles in trait bounds should be recoverable (Rustdoc regression (overflow evaluating the requirement …) #79459): Make cycle errors recoverable #102037
  • Recursion limit errors in trait bounds should be recoverable (nightly rustdoc reaches recursion limit while beta works fine #79506)
• Stabilization PR (see instructions on rustc-dev-guide)

Unresolved Questions

No unresolved questions known, this is "just hard".

Implementation history

• initial impl: Normalize <X as Y>::T for rustdoc #77467
• reverted due to breakage: Revert "Normalize <X as Y>::T for rustdoc" #79469
• re-added as unstable: Add -Z normalize-docs and enable it for compiler docs #79525

[jyn514]

@workingjubilee hmm, I'm not sure why you marked this as A-cli? The intention is to remove the flag completely when the blocking issues are fixed, and have this always on.