python - 模拟补丁装饰器 python

Question

嗨，我想模拟我的装饰器，因为我不想实际调用/执行这个函数。但我似乎找不到下面的解决方案是我的代码

# This is the decorator located in my project
# This is located in custom.mydecorators.decorator_file.custom_decorator
Base = declarative_base()


def custom_decorator(func):
  @wraps(func)
  def wrapper(*args, **kwargs):
    print("This message is still printed even when I try to patch this function")
    try:
        #code here
        my_var = CoolClass()
        retval = func(*args, **kwargs)
    except Exception as e:
        #rollback code here
        raise e

    return retval
  return wrapper

现在我正在尝试使用此代码修补它

patch('custom.mydecorators.decorator_file.custom_decorator', lambda x: x).start() 

class TestMockDecoratorsCallingClass(unittest.TestCase):
def test_should_return_success_if_decorators_are_mocked(self):
    # Code here

我的装饰器在非单元测试文件中正常工作。但是如果我模拟这个装饰器，它会失败说在赋值之前引用了局部变量“my_var”

注意： my_var 在我试图模拟/修补的装饰器内，即使我尝试修补它，打印消息仍然会执行