def test_circle_center_impossible(self):
start = Vec2d(-10, 0)
face = Vec2d(20, 0)
radius = 9
self.assertRaises(lambda: circle_center(start, face, radius), ValueError)
def test_circle_center(self):
start = Vec2d(97, 10)
face = Vec2d(6, 0)
radius = 5
center = circle_center(start, face, radius)
self.assertEquals(center, Vec2d(100, 6))