diff --git a/test/TrieExampleTest.mo b/test/TrieExampleTest.mo
index 3fbd4047..47f453ff 100644
--- a/test/TrieExampleTest.mo
+++ b/test/TrieExampleTest.mo
@@ -34,5 +34,5 @@ debug {
   func equalKV(a : (Text, Nat), b : (Text, Nat)) : Bool { a == b };
   assert (isSubSet(actual, expected, equalKV));
   assert (isSubSet(expected, actual, equalKV));
-
+  assert (Trie.isValid(t2, true));
 };