diff --git a/library/coretests/tests/ops.rs b/library/coretests/tests/ops.rs
index 921010774e28..121718f2167e 100644
--- a/library/coretests/tests/ops.rs
+++ b/library/coretests/tests/ops.rs
@@ -89,7 +89,8 @@ fn test_range_to_contains() {
     assert!(!(1u32..=5).contains(&6));
 }
 
-// This test covers `RangeBounds::contains` when the start is excluded.
+// This test covers `RangeBounds::contains` when the start is excluded,
+// which cannot be directly expressed by Rust's built-in range syntax.
 #[test]
 fn test_range_bounds_contains() {
     let r = (Bound::Excluded(1u32), Bound::Included(5u32));