def test_streighten(self):
self.assertEqual(
vector.streighten((1, 0), (-1, 0)),
((1, 0), (-1, 0)))
self.assertEqual(
vector.streighten((1, 1), (-1, 1)),
((1, 0), (-1, 0)))
self.assertEqual(
vector.streighten((1, 0.5), (-1, 0.5)),
((1, 0), (-1, 0)))
def test_length(self):
self.assertEqual(vector.length((0, 1)), 1)
self.assertEqual(vector.length((3, 4)), 5)
self.assertEqual(vector.length((0, 0)), 0)
