Safe opener - trying to take the fun from spamming Facebook with useless riddles :(

safe_opener.py

GIVEN_CLUES = (
    # Number, bulls, cows
    ('073', 1, 0),
    ('041', 0, 1),
    ('360', 0, 2),
    ('827', 0, 0),
    ('786', 0, 1)
)


def check_guess_validity(number, guess):
    if not (isinstance(number, str) and isinstance(guess, str)):
        raise TypeError("Number and guess must be strings.")
    if not (number.isdecimal() and guess.isdecimal()):
        raise ValueError("Number and guess must include only digits.")
    if len(number) != len(guess):
        raise ValueError("Number and guess must be in the same length.")


def _count_bulls(number, guess):
    return sum(1 for i, j in zip(number, guess) if i == j)


def _count_cows(number, guess):
    return sum(1 for i, j in zip(number, guess) if i != j and i in guess)


def get_bulls_and_cows(number, guess):
    check_guess_validity(number, guess)
    return [_count_bulls(number, guess), _count_cows(number, guess)]


def is_matching(guess, clues):
    for clue, *bulls_and_cows in clues:
        if not (get_bulls_and_cows(clue, guess) == bulls_and_cows):
            return False
    return True


def find_result(clues):
    num_of_digits = len(clues[0][0])
    for i in range(10**num_of_digits):
        guess = str(i).zfill(num_of_digits)
        if is_matching(guess, clues):
            return guess


if __name__ == '__main__':
    print(find_result(GIVEN_CLUES))

    # Tests section
    LONG_NUMBERS = (
        ('123', 3, 0),
        ('321', 1, 2),
        ('000', 0, 0),
        ('333', 1, 2),
    )
    tests = {
        _count_bulls: (
            ('123', '123', 3),
            ('987', '654', 0),
            ('987', '789', 1),
            ('987', '789', 1),
            ('981', '980', 2)
        ),
        _count_cows: (
            ('012', '012', 0),
            ('123', '321', 2),
            ('000', '111', 0),
            ('123', '345', 1),
            ('123', '312', 3),
        ),
        is_matching: (
            ('012', (('012', 3, 0),), True),
            ('123', LONG_NUMBERS, True),
            ('321', LONG_NUMBERS, False),
            ('987', LONG_NUMBERS, False),
            ('111', LONG_NUMBERS, False),
        )
    }
    for function, tests_for_function in tests.items():
        for *arguments, result in tests_for_function:
            assert function(*arguments) == result