完整的代码示例:

def decorator(class_):
    class Wrapper:
        def __init__(self, *args, **kwargs):
            self.instance = class_(*args, **kwargs)

        @classmethod
        def __getattr__(cls, attr):
            return getattr(class_, attr)
    return Wrapper


@decorator
class ClassTest:

    static_var = "some value"


class TestSomething:

    def test_decorator(self):
        print(ClassTest.static_var)
        assert True

尝试执行测试时,出现错误:

test/test_Framework.py F
test/test_Framework.py:37 (TestSomething.test_decorator)
self = <test_Framework.TestSomething object at 0x10ce3ceb8>

    def test_decorator(self):
>       print(ClassTest.static_var)
E       AttributeError: type object 'Wrapper' has no attribute 'static_var'

是否可以从装饰类访问静态字段?

最佳答案

虽然@martineau的答案可能更好地解决了您要解决的特定问题,但更通用的方法可能是使用create metaclass来在__getattr__实例上重新定义实例方法type(并且类是type的实例)。

def decorator(class_):
    class WrapperMeta(type):
        def __getattr__(self, attr):
            return getattr(class_, attr)

    class Wrapper(metaclass=WrapperMeta):
        def __init__(self, *args, **kwargs):
            self.instance = class_(*args, **kwargs)

    return Wrapper

这允许通过WrapperMeta.__getattr__传递对类本身的属性查找。

关于python - 从修饰的类访问静态字段,我们在Stack Overflow上找到一个类似的问题:https://stackoverflow.com/questions/47891737/

10-10 13:24