test: ensure rb node parents are equal

1 files changed, 9 insertions, 0 deletions

diff --git a/src/03/rb_tree.c b/src/03/rb_tree.c
index d1861f5..802791e 100644
--- a/src/03/rb_tree.c
+++ b/src/03/rb_tree.c
@@ -231,6 +231,15 @@ bool rb_equals(RBTree *tree, RBTree *other_tree) {
   if (!tree || !other_tree)
     return tree == other_tree;
 
+  if (tree->parent && !other_tree->parent)
+    return false;
+
+  if (!tree->parent && other_tree->parent)
+    return false;
+
+  if (tree->parent && tree->parent->value != other_tree->parent->value)
+    return false;
+
   return tree->value == other_tree->value
     && tree->colour == other_tree->colour
     && rb_equals(tree->left, other_tree->left)