ref: add default pattern to switch statement

TheAlgorithms · siriak · Sep 1, 2024 · May 3, 2024 · May 10, 2024 · May 10, 2024
commit 12effafefe4c96996ff2bf25facca88eb293e87c
@@ -304,5 +304,5 @@ private void postOrderRec(Node root, List<Integer> result) {
     /**
      * Enum to specify the order of traversal.
      */
-    public enum TraverseOrder { IN_ORDER, PRE_ORDER, POST_ORDER }
+    public enum TraverseOrder { IN_ORDER, PRE_ORDER, POST_ORDER, INVALID }
 }
@@ -9,6 +9,8 @@
 import java.util.LinkedList;
 import java.util.List;
 import java.util.stream.Stream;
+
+import org.junit.jupiter.api.Test;
 import org.junit.jupiter.params.ParameterizedTest;
 import org.junit.jupiter.params.provider.MethodSource;
 
@@ -70,6 +72,14 @@ public void testInsertThrowsExceptionForDuplicateKeys(int value) {
         assertThrows(IllegalArgumentException.class, () -> tree.insert(value));
     }
 
+    @Test
+    public void testInvalidTraversalOrderExceptionMessage() {
+        SplayTree tree = createComplexTree();
+        IllegalArgumentException exception = assertThrows(IllegalArgumentException.class,
+                () -> tree.traverse(SplayTree.TraverseOrder.INVALID));
+        assertEquals("Invalid traversal order: INVALID", exception.getMessage());
+    }
+
     private static Stream<SplayTree.TraverseOrder> traversalOrders() {
         return Stream.of(SplayTree.TraverseOrder.IN_ORDER, SplayTree.TraverseOrder.PRE_ORDER, SplayTree.TraverseOrder.POST_ORDER);
     }