检查是否已使用不同的参数多次调用函数

Question

假设我们有一个功能f(x,y)和另一个功能

def g():
       # ...
       f(i,j) # i,j vary and f is called multiple times
       # ...

我们要编写一个单元测试，以检查是否f调用了次数并具有正确的参数。

def test_g():
      with patch('mymodule.f') as function:
          assert function.gacs.call_count == correct_no_calls

有

function.assert_called_with(...)

但这仅指最后一次通话。因此，假设g电话f(1,2)，然后f(2,3)，function.assert_called_with(1,2)是False。

此外，还有

function.call_args_list

产生call具有正确参数的对象列表。将此列表与call我们在单元测试中创建的对象进行比较感觉很麻烦。call似乎是模拟库的内部类。

有一个更好的方法吗？我使用此设置来测试apply功能的并行执行。

Answer 1

测试Mock().mock_calls列表是否等于您提供的mock.call()对象列表：

self.assertEquals(function.mock_calls, [
    mock.call(1, 2),
    mock.call(2, 3),
])

这为您提供了精确的控制，需要匹配的调用顺序和数量。

的mock.call()类不是内部，它是指将被用于这样的断言。

Answer 2

甚至@MartinPieters的答案都是正确的，我认为这不是最好的方法。模拟提供assert_has_calls执行这种职责。

您的测试可能是：

function.assert_has_calls([mock.call(1, 2), mock.call(2, 3)])

mock.call帮手班在哪里做这些工作。

请注意，这是一个具有呼叫的呼叫，意味着呼叫列表应该在呼叫列表中，并且不相等。为了解决这个问题，我通常将自己的助手定义assert_is_calls()如下

def assert_is_calls(m, calls, any_order=False):
   assert len(m.mock_calls) == len(calls)
   m.assert_has_calls(calls, any_order=any_order)

那是简历的例子

>>> import mock
>>> f = mock.Mock()
>>> f(1)
<Mock name='mock()' id='139836302999952'>
>>> f(2)
<Mock name='mock()' id='139836302999952'>
>>> f.assert_has_calls([mock.call(1), mock.call(2)])
>>> f.assert_has_calls([mock.call(2), mock.call(1)])
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/home/damico/.local/lib/python2.7/site-packages/mock/mock.py", line 969, in assert_has_calls
    ), cause)
  File "/home/damico/.local/lib/python2.7/site-packages/six.py", line 718, in raise_from
    raise value
AssertionError: Calls not found.
Expected: [call(2), call(1)]
Actual: [call(1), call(2)]
>>> f.assert_has_calls([mock.call(2), mock.call(1)], any_order=True)
>>> f(3)
<Mock name='mock()' id='139836302999952'>
>>> f.assert_has_calls([mock.call(2), mock.call(1)], any_order=True)
>>> f.assert_has_calls([mock.call(1), mock.call(2)])
>>> assert len(f.mock_calls)==2
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AssertionError
>>> assert len(f.mock_calls)==3
>>> def assert_is_calls(m, calls, any_order=False):
...    assert len(m.mock_calls) == len(calls)
...    m.assert_has_calls(calls, any_order=any_order)
... 
>>> assert_is_calls(f, [mock.call(1), mock.call(2), mock.call(3)])
>>> assert_is_calls(f, [mock.call(1), mock.call(3), mock.call(2)])
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "<stdin>", line 3, in assert_is_calls
  File "/home/damico/.local/lib/python2.7/site-packages/mock/mock.py", line 969, in assert_has_calls
    ), cause)
  File "/home/damico/.local/lib/python2.7/site-packages/six.py", line 718, in raise_from
    raise value
AssertionError: Calls not found.
Expected: [call(1), call(3), call(2)]
Actual: [call(1), call(2), call(3)]
>>> assert_is_calls(f, [mock.call(1), mock.call(3), mock.call(2)], True)
>>> assert_is_calls(f, [mock.call(1), mock.call(3)], True)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "<stdin>", line 2, in assert_is_calls
AssertionError
>>>