def test_turn_raised_exception_for_incorrect_instruction(self):
     rover = Rover(self.coordinate, East())
     self.assertRaises(InstructionException, rover.turn("W"))
 def test_turn_changes_direction_for_R_instruction(self):
     rover = Rover(self.coordinate, East())
     rover.turn("R")
     self.assertEqual(rover.direction, South())