def test_dlist5(self):
dlist = DList()
dlist.add_before_element(1, None)
self.assertFalse(dlist.is_empty())
first = dlist.find_first(1)
self.assertEqual(first.item, 1)
dlist.add_after_element(2, first)
self.assertEqual(dlist.size(), 2)
def test_dlist(self):
dlist = DList()
self.assertTrue(dlist.is_empty())
self.assertEqual(dlist.size(), 0)
self.assertTrue(dlist.is_empty())
def test_dlist7(self):
dlist = DList(1)
dlist.remove_item(1)
self.assertTrue(dlist.is_empty())
def test_dlist6(self):
dlist = DList(1)
self.assertFalse(dlist.is_empty())
self.assertEqual(dlist.size(), 1)
def test_dlist3(self):
dlist = DList()
self.assertTrue(dlist.is_empty())
def test_dlist2(self):
dlist = DList()
dlist.add_before_element(1, None)
self.assertFalse(dlist.is_empty())
self.assertEqual(dlist.size(), 1)