def test_paintScheduling(self): """ Verify that L{TopWindow.repaint} schedules an actual paint to occur using the scheduling object passed to its initializer. """ paints = [] scheduled = [] root = TopWindow(lambda: paints.append(None), scheduled.append) # Nothing should have happened yet. self.assertEqual(paints, []) self.assertEqual(scheduled, []) # Cause a paint to be scheduled. root.repaint() self.assertEqual(paints, []) self.assertEqual(len(scheduled), 1) # Do another one to verify nothing else happens as long as the previous # one is still pending. root.repaint() self.assertEqual(paints, []) self.assertEqual(len(scheduled), 1) # Run the actual paint call. scheduled.pop()() self.assertEqual(len(paints), 1) self.assertEqual(scheduled, []) # Do one more to verify that now that the previous one is finished # future paints will succeed. root.repaint() self.assertEqual(len(paints), 1) self.assertEqual(len(scheduled), 1)