missing_docs does not trigger for types only used in exported fields of enumerations

[mathstuf]

IMO, this should be a compilation failure because although Foo is not explicitly exported, it is publicly visible via the Bar::A variant:

lib.rs:

#![deny(missing_docs)]

mod types;

pub use types::Bar;

types.rs:

pub struct Foo;

/// A bar.
pub enum Bar {
    /// A `Bar` variant.
    A(Foo),
}

Oddly enough, it seems to also be happy with the missing crate-level docs…

Using 1.14.0 (from Fedora's repository).

[mathstuf]

Hmm, even documenting it does not make it hyperlinked in the generated docs. What is the expected behavior here?

[durka]

You need to make the types module public.

[mathstuf]

Yeah, that makes the errors appear (as does re-exporting Foo from lib.rs). I'm not in front of a compiler right now, but IIRC, removing the pub from Foo is a compiler error; why is it not also a doc error?

[mathstuf]

Yep, removing the pub from Foo makes it error out that it can't leak private types. So, should the same behavior apply for missing_docs (since this is "leaking an undocumented public type")?

[Mark-Simulacrum]

Updated description to include ! in #![deny(missing_docs)], which made the lint error on the crate documentation, but still no errors about Foo itself.

[spacejam]

It was a bit of a surprise when I realized an important type that users are exposed to in one of my libraries was not properly documented, despite the crate specifying #![deny(missing_docs)]. My use case looked a bit like this.