def test_stop_cancels_transition(mock_change_to):
thread = Transition(0, 10)
thread.start()
thread.stop()
assert thread.is_stopped()
assert mock_change_to.call_count == 1
def test_run_unblur(mock_change_to):
thread = Transition(8, 2)
thread.start()
thread.join() # Wait for thread completion
assert mock_change_to.call_count == 6