FP single_component_path_imports

Lint name:

single_component_path_imports

I tried this code:

#[cfg(feature = "log")]
use log;

mod foo {
    use crate::log::warn;

    pub fn bar() {
        warn!("bar");
    }
}

pub fn bar() {
    foo::bar()
}

(I think it doesn't matter whether the feature log is turned on or off.)

I expected to see this happen: no warning, since the log import is used in an inner module.

Instead, this happened:

warning: this import is redundant
 --> src/lib.rs:3:1
  |
3 | use log;
  | ^^^^^^^^ help: remove it entirely
  |
  = note: `#[warn(clippy::single_component_path_imports)]` on by default
  = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#single_component_path_imports

Meta

• cargo clippy -V: clippy 0.1.53 (42816d61 2021-04-24)
• rustc -Vv:

  rustc 1.53.0-nightly (42816d61e 2021-04-24)
  binary: rustc
  commit-hash: 42816d61ead7e46d462df997958ccfd514f8c21c
  commit-date: 2021-04-24
  host: x86_64-apple-darwin
  release: 1.53.0-nightly
  LLVM version: 12.0.0
  

cc @ThibsG (re https://github.com/rust-lang/rust-clippy/pull/6905#event-4578609048)

Start by reproducing the provided Rust snippet with the single_component_path_imports lint enabled, then inspect the lint's implementation and existing tests. Done means the outer use log; import no longer produces a warning when the inner module uses crate::log::warn.