class QueueSizeTestCase(unittest.TestCase):
def setUp(self):
self.queue = Queue()
def test_size_should_return_the_number_of_items_in_the_queue(self):
self.assertEqual(self.queue.size(), 0)
self.queue.enqueue(1)
self.assertEqual(self.queue.size(), 1)
self.queue.enqueue(2)
self.assertEqual(self.queue.size(), 2)
self.queue.dequeue()
self.assertEqual(self.queue.size(), 1)
self.queue.front()
self.assertEqual(self.queue.size(), 1)
self.queue.rear()
self.assertEqual(self.queue.size(), 1)
class QueueFrontTestCase(unittest.TestCase):
def setUp(self):
self.queue = Queue()
self.queue.enqueue(1)
self.queue.enqueue(2)
self.queue.enqueue(3)
def test_front_should_return_the_first_item_of_its_items_list(self):
self.assertEqual(self.queue.front(), 1)
self.assertEqual(self.queue.front(), 1)
self.assertEqual(self.queue.front(), 1)
def test_front_should_return_none_if_queue_is_already_empty(self):
self.queue.dequeue()
self.queue.dequeue()
self.queue.dequeue()
self.assertEqual(self.queue.front(), None)
def test_front_should_not_decrement_queue_size(self):
self.assertEqual(self.queue.size(), 3)
self.queue.front()
self.assertEqual(self.queue.size(), 3)