diff --git a/library/alloc/tests/str.rs b/library/alloc/tests/str.rs index a1e819cf8f9e..d3a87c056cfb 100644 --- a/library/alloc/tests/str.rs +++ b/library/alloc/tests/str.rs @@ -1873,6 +1873,47 @@ mod pattern { "* \t", [Reject(0, 1), Reject(1, 2), Reject(2, 3),] ); + + // See #85462 + #[test] + fn str_searcher_empty_needle_after_done() { + // Empty needle and haystack + { + let mut searcher = "".into_searcher(""); + + assert_eq!(searcher.next(), SearchStep::Match(0, 0)); + assert_eq!(searcher.next(), SearchStep::Done); + assert_eq!(searcher.next(), SearchStep::Done); + assert_eq!(searcher.next(), SearchStep::Done); + + let mut searcher = "".into_searcher(""); + + assert_eq!(searcher.next_back(), SearchStep::Match(0, 0)); + assert_eq!(searcher.next_back(), SearchStep::Done); + assert_eq!(searcher.next_back(), SearchStep::Done); + assert_eq!(searcher.next_back(), SearchStep::Done); + } + // Empty needle and non-empty haystack + { + let mut searcher = "".into_searcher("a"); + + assert_eq!(searcher.next(), SearchStep::Match(0, 0)); + assert_eq!(searcher.next(), SearchStep::Reject(0, 1)); + assert_eq!(searcher.next(), SearchStep::Match(1, 1)); + assert_eq!(searcher.next(), SearchStep::Done); + assert_eq!(searcher.next(), SearchStep::Done); + assert_eq!(searcher.next(), SearchStep::Done); + + let mut searcher = "".into_searcher("a"); + + assert_eq!(searcher.next_back(), SearchStep::Match(1, 1)); + assert_eq!(searcher.next_back(), SearchStep::Reject(0, 1)); + assert_eq!(searcher.next_back(), SearchStep::Match(0, 0)); + assert_eq!(searcher.next_back(), SearchStep::Done); + assert_eq!(searcher.next_back(), SearchStep::Done); + assert_eq!(searcher.next_back(), SearchStep::Done); + } + } } macro_rules! generate_iterator_test {