def test_invalid_move_piece(self):
from towers import Tower, Rod, Piece, TowerError
tower = Tower()
tower.rods = [Rod() for i in range(3)]
tower.rods[0].pieces = [Piece(3 - i) for i in range(3)]
tower.rods[1].pieces = [Piece(4)]
with self.assertRaises(TowerError):
tower.move_piece(1, 0)
def test_move_piece(self):
from towers import Tower, Rod, Piece
tower = Tower()
tower.rods = [Rod() for i in range(3)]
tower.rods[0].pieces = [Piece(3 - i) for i in range(3)]
tower.move_piece(0, 2)
self.assertEqual(len(tower.rods[0].pieces), 2)
self.assertEqual(len(tower.rods[2].pieces), 1)
tower.move_piece(2, 0)
self.assertEqual(len(tower.rods[0].pieces), 3)
self.assertEqual(len(tower.rods[2].pieces), 0)