def test_breadthOrder():
    t = BinaryTreeSearch()
    t.add(5)
    t.add(9)
    t.add(4)
    t.add(14)
    t.add(7)
    t.add(6)
    t.add(3)
    actual = t.breadthOrder()
    expected = [
        5,
        4,
        9,
        3,
        7,
        14,
        6,
    ]
    assert actual == expected
def test_breadthOrder_empty():
    t = BinaryTreeSearch()
    actual = t.breadthOrder()
    expected = [None]
    assert actual == expected