    def test_stars_pattern(self):
        """
        Check that Stars custom pattern value works.
        """
        # Check that Stars randomly updates the Screen every frame.
        screen = MagicMock(spec=Screen, colours=8, unicode_aware=False)
        canvas = Canvas(screen, 10, 40, 0, 0)
        effect = Stars(canvas, 100, "TESTTESTTEST")
        effect.reset()
        my_buffer = [[(32, 7, 0, 0) for _ in range(40)] for _ in range(10)]
        for i in range(10):
            effect.update(i)
            self.assertTrue(self.check_canvas(
                canvas,
                my_buffer,
                lambda value: self.assertIn(chr(value[0]), " TES")))
Check that Stars custom pattern value works.
tests/test_effects.py