Rust-clippy: New lint: missing_panic_doc

[vanillajonathan]

What it does

Checks for missing documentation.

Lints

• Module not documented.
• Trait not documented.
• Trait method not documented.
• Enum not documented.
• Enum variant not documented.
• Struct not documented.
• Struct method not documented.
• Function not documented.
• Panic not documented.
• README.md missing.

[giraffate]

FYI rustc has a missing_doc lint and Clippy has a missing_docs_in_private_items.

[taiki-e]

• Panic not documented.

As Clippy has a similar lint for functions that return errors, I think it makes sense to have a lint for functions that may panics.

• Module not documented.
• Trait not documented.
• Trait method not documented.
• Enum not documented.
• Enum variant not documented.
• Struct not documented.
• Struct method not documented.
• Function not documented.

I think these are detected by missing_doc and missing_docs_in_private_items that @giraffate mentioned.

• README.md missing.

I think this is covered by cargo_common_metadata. (aside from whether it will be used for this purpose)

[ebroto]

I think these are detected by missing_doc and missing_docs_in_private_items that @giraffate mentioned.

Yep, you can check this in the playground.

Panic not documented.

As Clippy has a similar lint for functions that return errors, I think it makes sense to have a lint for functions that may panics.

There's also missing_safety_doc. I think it makes sense to add a lint for this. Since it's the only remaining case that it's not currently linted, I will change also the description of the issue to reflect that.

[camsteffen]

Duplicates #1974