def test_deletion_leaf(self):
bt = BinarySearchTree()
bt.insert_multiple_values([10, 20, 22, 3, 7, 4, 32, 900])
node, depth = bt.search(900)
self.assertEqual(node.value, 900)
self.assertEqual(depth, 4)
bt.delete(900)
node, _ = bt.search(900)
self.assertIsNone(node)
self.assertEqual(bt.in_order(), [3, 4, 7, 10, 20, 22, 32])
def test_deletion_first_use_case(self):
bt = BinarySearchTree()
bt.insert_multiple_values([10, 20, 22, 3, 7, 4, 32, 900])
node, depth = bt.search(4)
self.assertEqual(node.value, 4)
self.assertEqual(depth, 3)
bt.delete(4)
node, depth = bt.search(4)
self.assertIsNone(node)
self.assertEqual(bt.in_order(), [3, 7, 10, 20, 22, 32, 900])