https://doc.rust-jp.rs/book-ja/ch11-01-writing-tests.html#should_panic%E3%81%A7%E3%83%91%E3%83%8B%E3%83%83%E3%82%AF%E3%82%92%E7%A2%BA%E8%AA%8D%E3%81%99%E3%82%8B [[should_panic]]を使う。`expected`は[[panicマクロ]]のメッセージまで確認したいときに使う。 ```rust pub fn do_panic(message: &str) { panic!("{}", message); } #[cfg(test)] mod tests { use super::*; #[test] #[should_panic] fn it_panics() { do_panic("aaa"); } #[test] #[should_panic(expected = "aaa")] fn it_panics_aaa() { do_panic("aaa"); } #[test] #[should_panic(expected = "bbb")] fn it_panics_bbb() { // これは失敗する do_panic("aaa"); } } ```