def test_angle_of_velocity_is_determined_by_the_arctangent(self): start_position = Position() end_posotion = Position(3, 4) velocity = Velocity(start_position, end_posotion) self.assertTrue(velocity.angle() > 45) self.assertTrue(velocity.angle() < 90)
def test_angle_of_velocity_is_45_if_x_and_y_of_end_position_are_the_same( self): start_position = Position() end_position = Position(2, 2) velocity = Velocity(start_position, end_position) self.assertEquals(45, velocity.angle())