diff --git a/src/libcore/tests/iter.rs b/src/libcore/tests/iter.rs index 495483db555..19be1a07c5b 100644 --- a/src/libcore/tests/iter.rs +++ b/src/libcore/tests/iter.rs @@ -1249,6 +1249,23 @@ fn test_cloned() { assert_eq!(it.next_back(), None); } +#[test] +fn test_cloned_side_effects() { + let mut count = 0; + { + let iter = [1, 2, 3] + .iter() + .map(|x| { + count += 1; + x + }) + .cloned() + .zip(&[1]); + for _ in iter {} + } + assert_eq!(count, 2); +} + #[test] fn test_double_ended_map() { let xs = [1, 2, 3, 4, 5, 6];