def test_traverse_inorder():
    tree = BinarySearchTree()
    tree.add('bananas')
    tree.add('apples')
    tree.add('cucumbers')
    items = list(tree.traverse_inorder())
    assert items == ['apples', 'bananas', 'cucumbers']
def test_traverse_for_loop():
    tree = BinarySearchTree()
    tree.add('bananas')
    tree.add('apples')
    tree.add('cucumbers')
    items = []
    for item in tree.traverse_inorder():
        items.append(item)
    assert items == ['apples', 'bananas', 'cucumbers']