def test_right_linked_list_four():
tree = TreeNode(0)
tree.insert(1)
tree.insert(2)
tree.insert(3)
assert tree.balance() == -3
tree = tree.rebalance(tree)
assert tree.balance() == 1
def test_left_linked_list():
tree = TreeNode(2)
tree.insert(1)
tree.insert(0)
assert tree.balance() == 2
tree = tree.rebalance(tree)
assert tree.balance() == 0
treelist = [n for n in tree.depth_traversal("in")]
assert treelist == [0, 1, 2]
def test_balance():
tree = TreeNode(5)
assert tree.balance() == 0
tree.insert(1)
assert tree.balance() == 1
tree.insert(6)
assert tree.balance() == 0
tree.insert(3)
tree.insert(4)
assert tree.balance() == 2
def test_left_linked_list_four():
tree = TreeNode(3)
tree.insert(2)
tree.insert(1)
tree.insert(0)
assert tree.balance() == 3
assert tree.val == 3
tree = tree.rebalance(tree)
assert tree.balance() == -1
assert tree.val == 1
def test_complicated():
tree = TreeNode(50)
tree.insert(25)
tree.insert(30)
tree.insert(27)
tree.insert(26)
tree.insert(60)
tree.insert(70)
assert tree.balance() == 2
tree = tree.rebalance(tree)
assert tree.balance() == 1