rbtree: remove_node, pop_min

crates/rbtree/src/raw_node.rs

@@ -835,6 +835,13 @@ impl<N: UnsafeNode> RBTree<N> {
         None
     }
 
+    #[must_use]
+    pub fn pop_min(&mut self) -> Option<NonNull<N>> {
+        let min = self.root_handle().minimum_of()?;
+
+        self.remove_node(min)
+    }
+
     #[must_use]
     pub fn remove<Q>(&mut self, key: &Q) -> Option<NonNull<N>>
     where
@@ -845,6 +852,11 @@ impl<N: UnsafeNode> RBTree<N> {
             return None;
         };
 
+        self.remove_node(z)
+    }
+
+    #[must_use]
+    fn remove_node(&mut self, z: Handle<N>) -> Option<NonNull<N>> {
         // Y is either Z, the removed node in the case that Z has at most
         // one child, or Y is Z's successor which is guaranteed to have at most one
         // child (the right child).