如何在 python 中对装饰器工厂输入进行单元测试

Posted 2023-02-23

【中文标题】如何在 python 中对装饰器工厂输入进行单元测试

【英文标题】：How to unit test decorator factory inputs in python

【发布时间】：2019-11-25 12:53:01

【问题描述】：

我想对多个装饰函数的装饰器工厂输入进行单元测试。

我曾尝试模拟装饰器工厂，但这并没有帮助我将特定的装饰器工厂调用关联到特定的装饰函数。相反，我只是按照在文件中调用的顺序获得装饰工厂调用的列表。

# decorator.py
from decorator_def import decorator_factory

@decorator_factory(2)
def say_goodbye():
    print 'goodbye'

@decorator_factory(4)
def say_what():
    print 'what'

import functools

def decorator_factory(input=1):
    def decorator(func):
        @functools.wraps(func)
        def say_hello(*_args):
            print 'hello '*input
            _result = func(*_args)
            return _result
        return say_hello
    return decorator

我想要这样的东西：

#pseudo
def test_decorated_say_goodbye():
    assert decorator_factory_input_for_say_goodbye == 2

def test_decorated_say_what():
    assert decorator_factory_input_for_say_what == 4

我最接近的是下面。 （基于这个答案https://***.com/a/37890916/8196029。） 这不是我想要的，因为它只是一个与修饰函数名称无关的调用列表：

import unittest
import imp

from mock import patch, MagicMock, call

import decorator


class TestDecorated(unittest.TestCase):
    def setUp(self):
        def kill_patches():
            patch.stopall()
            imp.reload(decorator)
        self.addCleanup(kill_patches)

        self.mocked_df = MagicMock()
        patch('decorator_def.decorator_factory', self.mocked_df).start()
        imp.reload(decorator)

    def test_decorated_order(self):
        df_call_args_expected = [
            call(2),  # say_goodbye
            call(4)  # say_what
        ]

        assert self.mocked_df.call_args_list == df_call_args_expected

【参考方案1】：

找到了一条路：

from decorator import say_what, say_goodbye


def test_decorated_say_what():
    assert say_what.__code__.co_freevars[1] == 'input'
    assert say_what.__closure__[1].cell_contents == 4


def test_decorated_say_goodbye():
    assert say_goodbye.__code__.co_freevars[1] == 'input'
    assert say_goodbye.__closure__[1].cell_contents == 2