`while_let_loop` suggests wrong name to use in pattern

When running clippy on this code

fn foo() -> Option<usize> {
    todo!()
}

fn main() {
    loop {
        let x = match foo() {
            Some(n) => n,
            None => break,
        };
        println!("{}", x);
    }
}

it (rightly) suggests that while let could be used instead. However, the suggested fix is try: 'while let Some(n) = foo() { .. }' (playground link), taking the n from the pattern inside the match instead of the x from let x. Carrying out this replacement introduces compilation errors, as x is now undefined.

Expected behaviour:

Suggest trying while let Some(x), taking the variable name that binds the result of the match expression.

Meta

• cargo clippy -V: clippy 0.1.52 (9bc8c42b 2021-05-09)
• rustc -Vv:

  rustc 1.52.1 (9bc8c42bb 2021-05-09)
  binary: rustc
  commit-hash: 9bc8c42bb2f19e745a63f3445f1ac248fb015e53
  commit-date: 2021-05-09
  host: x86_64-pc-windows-msvc
  release: 1.52.1
  LLVM version: 12.0.0
  

Reproduce the report with the supplied Rust snippet and run cargo clippy to observe the while_let_loop suggestion. Trace the lint implementation and its tests from the Clippy source, then verify that the suggested pattern preserves the variable used by println! and no longer causes compilation errors.