Cargo doc spuriously links to random enum variant fields instead of marking links broken

[tnull]

Problem

In lightningdevkit/rust-lightning#2027 we stumbled across a bug in cargo doc, as it checking for broken links didn't work for a now renamed field that is also present in another enum variant.

Steps

A minimal example is this, which doesn't fail, but should:

#![deny(broken_intra_doc_links)]

/// Referring to [`TestEnum::Variant1::field_name`]
pub enum TestEnum {
	Variant1 {},
	Variant2 {
		field_name: u64,
	}
}

If TestEnum::Variant1::field_name is present the docs indeed link to the right variant. If it is missing, cargo doc gladly makes the TestEnum::Variant1::field_name link point to TestEnum::Variant2::field_name, without throwing an error.

Possible Solution(s)

No response

Notes

No response

Version

> cargo --version
cargo 1.65.0 (4bc8f24d3 2022-10-20)

[ehuss]

Transferred to rust-lang/rust, as rustdoc issues are tracked here.

[jyn514]

rust/src/librustdoc/passes/collect_intra_doc_links.rs

Line 341 in 3574b1a

if let Some(field) = def.all_fields().find(|f| f.name == variant_field_name) {

probably needs to consider variant_name, not just variant_field_name and path.

[jyn514]

https://doc.rust-lang.org/stable/nightly-rustc/rustc_middle/ty/adt/struct.AdtDef.html#method.variant_with_id is likely what you want and from there you can iterate variant.fields.