def test_has_next_returns_false_at_end_of_iteration(self):
peaker = Peaker((x for x in 'ab'))
self.assertTrue(peaker.has_next())
peaker.next()
self.assertTrue(peaker.has_next())
peaker.next()
self.assertFalse(peaker.has_next())
def test_stop_iteration_raised(self):
peaker = Peaker((x for x in 'ab'))
self.assertEqual(peaker.next(), 'a')
self.assertEqual(peaker.next(), 'b')
with self.assertRaises(StopIteration):
peaker.next()
def test_next_does_move_stream_forward(self):
generator = cycle('abc')
peaker = Peaker(stream=generator)
self.assertEqual(peaker.next(), 'a')
self.assertEqual(peaker.next(), 'b')