BTreeMap: making PartialCmp/PartialEq explicit and tested

1 files changed, 33 insertions, 0 deletions

diff --git a/library/alloc/src/collections/btree/node/tests.rs b/library/alloc/src/collections/btree/node/tests.rs
index 54c3709821a..2ef9aad0ccd 100644
--- a/library/alloc/src/collections/btree/node/tests.rs
+++ b/library/alloc/src/collections/btree/node/tests.rs
@@ -1,4 +1,5 @@
 use super::*;
+use core::cmp::Ordering::*;
 
 #[test]
 fn test_splitpoint() {
@@ -25,6 +26,38 @@ fn test_splitpoint() {
 }
 
 #[test]
+fn test_partial_cmp_eq() {
+    let mut root1: Root<i32, ()> = Root::new_leaf();
+    let mut leaf1 = unsafe { root1.leaf_node_as_mut() };
+    leaf1.push(1, ());
+    root1.push_internal_level();
+    let root2: Root<i32, ()> = Root::new_leaf();
+
+    let leaf_edge_1a = root1.node_as_ref().first_leaf_edge().forget_node_type();
+    let leaf_edge_1b = root1.node_as_ref().last_leaf_edge().forget_node_type();
+    let top_edge_1 = root1.node_as_ref().first_edge();
+    let top_edge_2 = root2.node_as_ref().first_edge();
+
+    assert!(leaf_edge_1a == leaf_edge_1a);
+    assert!(leaf_edge_1a != leaf_edge_1b);
+    assert!(leaf_edge_1a != top_edge_1);
+    assert!(leaf_edge_1a != top_edge_2);
+    assert!(top_edge_1 == top_edge_1);
+    assert!(top_edge_1 != top_edge_2);
+
+    assert_eq!(leaf_edge_1a.partial_cmp(&leaf_edge_1a), Some(Equal));
+    assert_eq!(leaf_edge_1a.partial_cmp(&leaf_edge_1b), Some(Less));
+    assert_eq!(leaf_edge_1a.partial_cmp(&top_edge_1), None);
+    assert_eq!(leaf_edge_1a.partial_cmp(&top_edge_2), None);
+    assert_eq!(top_edge_1.partial_cmp(&top_edge_1), Some(Equal));
+    assert_eq!(top_edge_1.partial_cmp(&top_edge_2), None);
+
+    root1.pop_internal_level();
+    unsafe { root1.into_ref().deallocate_and_ascend() };
+    unsafe { root2.into_ref().deallocate_and_ascend() };
+}
+
+#[test]
 #[cfg(target_arch = "x86_64")]
 fn test_sizes() {
     assert_eq!(core::mem::size_of::<LeafNode<(), ()>>(), 16);