def test_circular_buffer_with_many_characters(self):
circle = CircularBuffer('test')
result = [circle.next() for _ in range(8)]
expected = ['t', 'e', 's', 't', 't', 'e', 's', 't']
self.assertEqual(result, expected)
def test_circular_buffer_with_one_character(self):
circle = CircularBuffer('z')
result = [circle.next() for _ in range(3)]
expected = ['z', 'z', 'z']
self.assertEqual(result, expected)
