1 error: called `.err().expect()` on a `Result` value
2 --> $DIR/err_expect.rs:10:16
4 LL | test_debug.err().expect("Testing debug type");
5 | ^^^^^^^^^^^^ help: try: `expect_err`
7 = note: `-D clippy::err-expect` implied by `-D warnings`
9 error: aborting due to previous error