src/tools/clippy/tests/ui/duplicate_underscore_argument.stderr

   1 error: `darth` already exists, having another argument having almost the same name makes code comprehension and documentation more difficult
   2  --> $DIR/duplicate_underscore_argument.rs:7:23
   3   |
   4 7 | fn join_the_dark_side(darth: i32, _darth: i32) {}
   5   |                       ^^^^^
   6   |
   7   = note: `-D duplicate-underscore-argument` implied by `-D warnings`
   8