我使用这个的目的是为了测试和跑一下 fluent python 2nd edition 的代码。

发现，这就是一个模块，其实还是很简单的，相当于测试模块，但是又有不同，总是，这个也是可以模拟交互式的 Python 的，

# ex01.py
'''
>>> beer_card = Card('7', 'diamonds')
>>> beer_card
Card(rank='7', suit='diamonds')
'''

import collections

Card = collections.namedtuple('Card', ['rank', 'suit'])

class FrenchDeck:
    ranks = [str(n) for n in range(2, 11)] + list('JQKA')
    suits = 'spades diamonds clubs hearts'.split()

    def __init__(self) -> None:
        self._cards = [Card(rank, suit) for suit in self.suits
                       for rank in self.ranks]

    def __len__(self):
        return len(self._cards)

    def __getitem__(self, position):
        return self._cards[position]

if __name__ == "__main__":
    import doctest
    doctest.testmod()

上面的代码，我们直接 python [ex01.py](<http://ex01.py>) 就行了，如果没有问题，那么，什么都不会输出，而如果我们想看到详细的信息，那么，可以加一个 -v 参数，python ex01.py -v ，输出的结果如下，

PyCodes/fluentpy2ed/ch01 via 🐍 v3.12.4 
❯ python ex01.py -v
Trying:
    beer_card = Card('7', 'diamonds')
Expecting nothing
ok
Trying:
    beer_card
Expecting:
    Card(rank='7', suit='diamonds')
ok
5 items had no tests:
    __main__.Card
    __main__.FrenchDeck
    __main__.FrenchDeck.__getitem__
    __main__.FrenchDeck.__init__
    __main__.FrenchDeck.__len__
1 items passed all tests:
   2 tests in __main__
2 tests in 6 items.
2 passed and 0 failed.
Test passed.

当然，我们也可以给 testmod 方法里面传递 verbose = True ，这样，就不用我们在执行 python 的时候加 -v 参数了，

# ex01.py
'''
>>> beer_card = Card('7', 'diamonds')
>>> beer_card
Card(rank='7', suit='diamonds')
'''

import collections

Card = collections.namedtuple('Card', ['rank', 'suit'])

class FrenchDeck:
    ranks = [str(n) for n in range(2, 11)] + list('JQKA')
    suits = 'spades diamonds clubs hearts'.split()

    def __init__(self) -> None:
        self._cards = [Card(rank, suit) for suit in self.suits
                       for rank in self.ranks]

    def __len__(self):
        return len(self._cards)

    def __getitem__(self, position):
        return self._cards[position]

if __name__ == "__main__":
    import doctest
    doctest.testmod(verbose=True)