def test_change_starting_index(self): s = Span(1, 10, 10, index=1) assert s.a == 1 assert s.b == 10 assert s.c == 10 assert s.index == 1 assert len(s) == 9 s2 = s.reindex(0) assert s2.a == 0 assert s2.b == 9 assert s2.c == 9 assert s2.index == 0 assert len(s) == 9 s2 = s.reindex(-5) assert s2.a == 0 - 5 assert s2.b == 9 - 5 assert s2.c == 9 - 5 assert s2.index == -5 assert len(s) == 9