def test_pop_without_index(self): """ Test the pop method without index """ dlist = DiskList() dlist.append('0') dlist.append('1') dlist.append('2') dlist.append('3') result = dlist.pop() self.assertTrue(dlist[0] == '0' and dlist[1] == '1' and dlist[2] == '2' and result == '3' and len(dlist) == 3)