我正在尝试使用Python unittest测试一个类,但测试套件似乎在修改基类
这里有一些用于演示问题的伪代码:
班级
// module cards...
class deck():
def __init__(self, cards):
self.__cards = cards
def __len__(self):
return len(self.__cards)
def draw(self, n = 1):
'''
remove and return n cards
from internal card list
n -- integer
@return list removed
'''
removed = self.__cards[0:n]
remaining = self.__cards[n:]
self.__cards = remaining
return removed
def addOne(self, card):
'''
add single card to the deck
'''
self.__cards.append(card)
def addMany(self, cards):
'''
add many cards to the deck
'''
self.__cards.extend(cards)
填充实例的fixture,可能是文件或数据库查询的输出
//source
src = [
{
'id' : 1,
'name' : 'one',
'description' : 'this is one'
},
{
'id' : 2,
'name' : 'two',
'description' : 'this is two'
},
{
'id' : 3,
'name' : 'three',
'description' : 'this is three'
},
{
'id' : 4,
'name' : 'four',
'description' : 'this is four'
},
{
'id' : 5,
'name' : 'five',
'description' : 'this is five'
}
]
测试
from source import src
import cards
def test_drawRemovesOne(self):
deck = cards.deck(src)
self.assertTrue(callable(deck.draw))
# single card
deckSize = len(deck)
drawnCard = deck.draw(1)
self.assertEqual(drawnCard[0]['id'], 1)
self.assertEqual(4, len(deck))
self.assertEqual(len(drawnCard), 1)
def test_drawRemovesMany(self):
deck = cards.deck(src)
deckSize = len(deck)
drawnCards = deck.draw(3)
self.assertEqual(drawnCards[0]['id'], 1)
self.assertEqual(drawnCards[1]['id'], 2)
self.assertEqual(drawnCards[2]['id'], 3)
self.assertEqual(len(deck), 2)
self.assertEqual(len(drawnCards), 3)
'''
INVALIDATES PREVIOUS TESTS...
def test_addOne(self):
deck = cards.deck(src)
card = {
'id' : 9,
'name' : 'nine',
'description' : 'this is nine'
}
deckSize = len(deck)
deck.addOne(card)
newDeckSize = len(deck)
self.assertTrue(newDeckSize == deckSize + 1)
'''
编辑:发布真实片段
第一次测试通过,但随后在第二次测试实施时失败。看起来似乎有一个对测试方法共享的类的引用,尽管看起来是新的实例。
我在Python中只做了一点名工作,这是我不知道的一些语言特性的结果吗?
答案 0 :(得分:1)
请参阅此代码
>>> class Deck:
... def __init__(self, cards):
... self.cards = cards
>>> l0 = [1, 2, 3]
>>> d1 = Deck(l0)
>>> d2 = Deck(l0)
>>> d1.cards
0: [1, 2, 3]
>>> d2.cards
1: [1, 2, 3]
>>> d1.cards.append(4)
>>> d2.cards
2: [1, 2, 3, 4] # d1 and d2 share the same list for cards
您可以使用deck = cards.deck(src)
启动所有测试,但我不知道src
的来源。如果它没有在setUp方法中创建为新对象,那么它可以在测试用例之间共享。