Function public_module_names 

fn public_module_names(items: &[Item], scope: &str) -> Vec<String>

The scopes of the pub mod declarations reachable from one module body.

Recurses through inline pub mod bodies, whose submodule files live under the inline module’s own directory: pub mod a { mod b; } in lib.rs looks for src/a/b.rs, so the scope path grows even though the file does not change.