gistfile1.py

class BowlingScorer:
    def __init__(self, rolls):
        rolls = rolls[:]
        self.score = sum(self.score_frame(rolls) for _ in range(10))

    def score_frame(self, rolls_left):
        roll1 = rolls_left.pop(0)
        if roll1 == 10:
            return 10 + rolls_left[0] + rolls_left[1]

        roll2 = rolls_left.pop(0)
        if roll1 + roll2 == 10:
            return 10 + rolls_left[0]

        return roll1 + roll2


def describe_bowling_score():
    def should_be_0_for_all_gutter_balls():
        assert BowlingScorer([0] * 20).score == 0

    def should_be_150_for_all_spares():
        assert BowlingScorer([5] * 21).score == 150

    def should_be_300_for_perfect_game():
        assert BowlingScorer([10] * 12).score == 300

    def should_be_90_for_9_pins_per_frame():
        assert BowlingScorer([4, 5] * 10).score == 90