Detect pub use statements

[i509VCB]

What it does

Detects usage of pub use. This statement effectively exports a type or module as if it is a member of the current module.

Lint Name

detect_pub_use

Category

pedantic

Advantage

• sometimes when reexporting multiple types, it isn't clear you have exported all the types, resulting in some types which should be public but may not be explicitly named in code.
• a pub use statement for crate types may be better exposed by placing the type in a public module instead of explicitly exporting it and making private details crate private or module private.

Drawbacks

• sometimes this is intended, especially for opaque retuen types or reexporting a crate for library usage, hence the pedantic categorization. This might be better done via an impl Trait return type if the type needs to be private details of a library.
• the issue being solved might make more sense as an specialized lint working off public visibility.

Example

mod priv_mod {...}

pub use self::priv_mod::PublicType;

Could be placed in a public module, or the module the type inhabits made public.

[i509VCB]

I guess I'll include an example of the issue I am trying to have warnings for:
https://play.rust-lang.org/?version=stable&mode=debug&edition=2021&gist=f2cccd05143720f55ffa44c8c63ee5da

[yoav-lavi]

I don't mind taking this, I think it makes the most sense to put this in restrictions though, I'll prepare a PR and worst case we can change it

[yoav-lavi]

@rustbot claim