def test_circle_linked(self):
cll = CircleLinkedList()
cll.add(12)
cll.add(24)
cll.add(48)
cll.add(96)
link_first = cll.get_link(12)
self.assertEqual(None, link_first.prev)
self.assertEqual(24, link_first.next)
self.assertEqual(None, link_first.start)
self.assertEqual(96, link_first.end)
link_middle = cll.get_link(24)
self.assertEqual(12, link_middle.prev)
self.assertEqual(48, link_middle.next)
self.assertEqual(None, link_middle.start)
self.assertEqual(None, link_middle.end)
link_last = cll.get_link(48)
self.assertEqual(24, link_last.prev)
self.assertEqual(96, link_last.next)
self.assertEqual(None, link_last.start)
self.assertEqual(None, link_last.end)
link_last = cll.get_link(96)
self.assertEqual(48, link_last.prev)
self.assertEqual(None, link_last.next)
self.assertEqual(12, link_last.start)
self.assertEqual(None, link_last.end)
self.assertEqual(False, cll.empty())
def test_not_empty(self):
cll = CircleLinkedList()
cll.add(12)
self.assertEqual(False, cll.empty())
def test_empty(self):
cll = CircleLinkedList()
self.assertEqual(True, cll.empty())