def test_delta_insert_text(self):
delta = Delta()
assert delta.ops == []
delta = (delta.insert('Hello',
None).insert(' ', None).insert('World!', None))
assert len(delta.ops) == 1, delta.ops
assert delta.ops == [Insert('Hello World!', None)]
delta.insert('\n', None)
delta.insert('Hello World', None)
delta.insert('!', None)
assert len(delta.ops) == 1, delta.ops
assert delta.ops == [Insert('Hello World!\nHello World!', None)]
def test_empty_ops(self):
delta = Delta()
delta.insert('').delete(0).retain(0)
assert len(delta.ops) == 0