rockpaperscissors_test.py

import unittest
from parameterized import parameterized

PAPER = "paper"
SCISSORS = "scissors"
ROCK = "rock"

DRAW = 0
PLAYER_ONE_WINS = 1
PLAYER_TWO_WINS = 2


def play_round(player1, player2):
    return {
        ROCK: [ROCK, SCISSORS, PAPER],
        PAPER: [PAPER, ROCK, SCISSORS],
        SCISSORS: [SCISSORS, PAPER, ROCK]
    }[player1].index(player2)


def play_game(rounds):
    score = [0, 0, 0]

    for round_winner in rounds:
        score[round_winner] += 1
        try:
            return score[1:].index(2) + 1
        except ValueError:
            pass

    return None


class RockPaperScissorsTest(unittest.TestCase):

    @parameterized.expand([
        (ROCK, SCISSORS, PLAYER_ONE_WINS),
        (SCISSORS, ROCK, PLAYER_TWO_WINS)
    ]
    )
    def test_rock_blunts_scissors(self, player1, player2, winner):
        self.assertEqual(winner, play_round(player1, player2))

    @parameterized.expand([
        (PAPER, ROCK, PLAYER_ONE_WINS),
        (ROCK, PAPER, PLAYER_TWO_WINS)
    ]
    )
    def test_paper_wraps_rock(self, player1, player2, winner):
        self.assertEqual(winner, play_round(player1, player2))

    @parameterized.expand([
        (SCISSORS, PAPER, PLAYER_ONE_WINS),
        (PAPER, SCISSORS, PLAYER_TWO_WINS)
    ]
    )
    def test_scissors_cut_paper(self, player1, player2, winner):
        self.assertEqual(winner, play_round(player1, player2))

    @parameterized.expand([
        (ROCK, ROCK, DRAW),
        (PAPER, PAPER, DRAW),
        (SCISSORS, SCISSORS, DRAW)
    ]
    )
    def test_draw_when_same(self, player1, player2, winner):
        self.assertEqual(winner, play_round(player1, player2))

    @parameterized.expand([
        (ROCK, SCISSORS, PLAYER_ONE_WINS),
        (PAPER, SCISSORS, PLAYER_TWO_WINS)
    ]
    )
    def test_first_player_with_two_points_wins_game(self, player1, player2, winner):
        self.assertEqual(winner, play_game([
            play_round(player1, player2),  # player 1 wins round
            play_round(player2, player1),  # player 2 wins round
            play_round(player1, player2)   # player 1 wins round
        ]))

    def test_draws_dont_count_in_game(self):
        self.assertEqual(None, play_game([
            play_round(ROCK, ROCK),
            play_round(ROCK, ROCK),
            play_round(ROCK, ROCK),
            play_round(ROCK, ROCK)
        ]))


if __name__ == '__main__':
    unittest.main()