問題描述

出于測試原因，我需要能夠模擬在其他地方使用的裝飾的內部/原始功能:

For testing reasons, I need to be able to mock the inner/original function of a decorated one which is used somewhere else:

在 mydecorator.py 中:

In mydecorator.py:

def my_decorator(f):
    def wrapped_f():
        print "decorated"
        f()
    return wrapped_f


@my_decorator
def function_to_be_mocked():
    print 'original'


def function_to_be_mocked_undecorated():
    print 'original'


def run_decorated():
    function_to_be_mocked()


def run_undecorated():
    decorated_funtion = my_decorator(function_to_be_mocked_undecorated)
    decorated_funtion()

如您所見，我有幾個版本的原始函數 function_to_be_mocked，一個帶有裝飾器 my_decorator，另一個是裸".運行器函數 run_decorated() 調用 function_to_be_mocked 的修飾版本， run_undecorated() 調用未修飾版本并手動"應用修飾器.兩者的結果是一樣的:

As you can see, I have several versions of the original function function_to_be_mocked, one with the decorator my_decorator and one 'naked'. The runner function run_decorated() calls the decorated version of function_to_be_mocked and run_undecorated() calls the undecorated version and applies the decorator 'manually'. The result of both are the same:

decorated
original

現在我想測試 runner 函數，但我需要模擬原始函數 function_to_be_mocked 并且模擬的版本應該被裝飾:

Now I want to test the runner function but I need to mock the original function function_to_be_mocked but also the mocked version should be decorated:

import unittest
import mydecorator
from mock import patch

def mock_function():
    print 'mockified'

class Test(unittest.TestCase):

    @patch('mydecorator.function_to_be_mocked_undecorated')
    def test_undecorated_mocked(self, mock_function_to_be_mocked_undecorated):
        mydecorator.function_to_be_mocked_undecorated = mock_function
        mydecorator.run_undecorated()
        assert 1==0

    @patch('mydecorator.function_to_be_mocked')
    def test_decoratorated_mocked(self, mock_function_to_be_mocked):
        mydecorator.function_to_be_mocked = mock_function
        mydecorator.run_decorated()
        assert 1==0

這對于未修飾的版本 test_undecorated_mocked 可以正常工作:

This works as expected for the undecorated version test_undecorated_mocked:

decorated
mockified

但裝飾版給出:

mockified

所以裝飾器消失了.

是否可以讓裝飾版本以與未裝飾版本相同的方式工作，其中手動"應用裝飾器?

Is it possible to get the decorated version working in the same way as the undecorated version, where the decorator is applied 'manually'?

我嘗試在裝飾器中暴露內部函數，但沒有成功.

I tried to expose the inner function in the decorator without success.

我看到了這個問題 你如何模擬一個在單元測試中應用了裝飾器的函數?但這對我沒有幫助.

I saw this question How do you mock a function which has decorator apply to it in a unit test? but this doesn't help me.

推薦答案

Python在加載模塊時應用裝飾器，所以在test_decoratorated_mocked<中設置function_to_be_mocked為mock_function/code> 確實會將該函數更改為未修飾的函數.

mydecorator.function_to_be_mocked = mydecorator.my_decorator(mock_function)