无法修补功能的功能

Question

我对打补丁还很陌生，我运行遇到了一些我不知道如何打补丁的问题。基本上，在我要测试的文件中，有方法 difficult_method()。它看起来有点像这样：

from import_location import User

def difficult_method():
  ids = list_of_ids
  for id in list_of_ids:
    try:
      user = User.query.filter(User.id == user_id).all()[0]
    except:
      continue
    #do lots of stuff

我想模拟的代码是 User.query.filter(User.id == user_id).all()，据我所知，它可以 return 一个静态列表。我将如何替换看起来像这样的代码中的那一行：

from mock import patch

@patch(#what would go here?)
def test_difficult_method(): 
  from file_to_test import difficult_method
  assert difficult_method() returns ...

Answer 1

我想通了！关键是创建一个 MockUser class，像这样：

user = #creating a user

class MockFilter(object):
  def all(self):
    return [user]


class MockQuery(object):

  def filter(self, match):
    return MockFilter()


class MockUser(object):
  query = MockQuery()
  id = '2'

然后我像这样修补它：

from mock import patch

@patch('import_location.User', MockUser)
def test_difficult_method(): 
  from file_to_test import difficult_method
  assert difficult_method() returns ...

无法修补功能的功能

Trouble patching a function of a function

python

mocking

monkeypatching