diff options
Diffstat (limited to 'library/alloc/src')
| -rw-r--r-- | library/alloc/src/collections/btree/map.rs | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/library/alloc/src/collections/btree/map.rs b/library/alloc/src/collections/btree/map.rs index 2b8ddf14ff3..addcc71a2d4 100644 --- a/library/alloc/src/collections/btree/map.rs +++ b/library/alloc/src/collections/btree/map.rs @@ -3247,9 +3247,15 @@ impl<'a, K: Ord, V, A: Allocator + Clone> CursorMutKey<'a, K, V, A> { #[unstable(feature = "btree_cursors", issue = "107540")] pub fn remove_next(&mut self) -> Option<(K, V)> { let current = self.current.take()?; + if current.reborrow().next_kv().is_err() { + self.current = Some(current); + return None; + } let mut emptied_internal_root = false; let (kv, pos) = current .next_kv() + // This should be unwrap(), but that doesn't work because NodeRef + // doesn't implement Debug. The condition is checked above. .ok()? .remove_kv_tracking(|| emptied_internal_root = true, self.alloc.clone()); self.current = Some(pos); @@ -3270,9 +3276,15 @@ impl<'a, K: Ord, V, A: Allocator + Clone> CursorMutKey<'a, K, V, A> { #[unstable(feature = "btree_cursors", issue = "107540")] pub fn remove_prev(&mut self) -> Option<(K, V)> { let current = self.current.take()?; + if current.reborrow().next_back_kv().is_err() { + self.current = Some(current); + return None; + } let mut emptied_internal_root = false; let (kv, pos) = current .next_back_kv() + // This should be unwrap(), but that doesn't work because NodeRef + // doesn't implement Debug. The condition is checked above. .ok()? .remove_kv_tracking(|| emptied_internal_root = true, self.alloc.clone()); self.current = Some(pos); |