rustdoc: Tracking issue for lint `rustdoc::missing_doc_code_examples`

[Nemo157]

This is a tracking issue for the lint rustdoc::missing_doc_code_examples.
The feature gate for the issue is #![feature(rustdoc_missing_doc_code_examples)].

Note

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Instead, open a dedicated issue for the specific matter or post in the #t-rustdoc Zulip channel.

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Steps

• Implement the lint [rustdoc] Add lint for doc without codeblocks #54349
• Adjust documentation (see instructions on rustc-dev-guide)
• Stabilization PR (see instructions on rustc-dev-guide)

Unresolved Questions

• Rustdoc lints don't fire for pub re-exports #77230
• rustdoc::missing_doc_code_examples inconsistent with Rust API Guidelines #87858

Implementation history

• [rustdoc] Add lint for doc without codeblocks #54349
• Separate missing_doc_code_examples from intra-doc links #74855
• Missing doc examples lint improvements #75776
• Document lint missing_doc_code_examples is nightly-only #76212
• Don't warn for missing_doc_examples when item is #[doc(hidden)] #76716
• Make rustdoc lints a tool lint instead of built-in #80527
• Don't lint about missing code examples in derived traits #88735
• Allow missing code examples in trait impls. #88745
• Add test to ensure that the missing_doc_code_examples is not triggered on foreign trait implementations #90098

[jplatte]

When this lands, could there be a new lint group like rustdoc::all that activates all non-"restriction" rustdoc lints? All the current lints in from https://doc.rust-lang.org/rustdoc/lints.html are very useful to deny in CI, but this one obviously isn't (for most people).

[peter-lyons-kehl]

Please add #109592 and its PR (if accepted), and #109601.

[peter-lyons-kehl]

@jplatte FYI related to rustdoc::all

• rustdoc::missing_doc_code_examples inconsistent with Rust API Guidelines #87858, and
• rustdoc::all in src/librustdoc/lint.rs -> register_lints(...): https://github.com/rust-lang/rust/blob/master/src/librustdoc/lint.rs#L195.