rust-lang / rust-lang/rust

Lint on `mod foo {}` inside of `foo.rs`

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#141,385 4 comments 0 reactions 1 assignee View on GitHub

@chenyukang is already working on this.

Since Oct 12, 2025.

A-lints C-feature-request D-newcomer-roadblock E-mentor P-low T-compiler T-lang
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Rust
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Description

One newcomer mistake is getting confused by the module system ending up with crate::module::module by having pub mod module {} inside of module.rs. We should have a lint that detects this case and gently nudges the user towards the more likely intended structure.

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