用 arguments 装饰 Class 声明

Question

I'm trying to create a Class representing a regex to execute for my application. For each regex I have a link to the regex101.com page where users can find unit tests. I wanna use this solution to have near the class declaration this link but without having them in the class code. The code I think about has to look like this:

class TestUrl(object):
    def __init__(self, url) -> None:
        self.url = url
        
    def __call__(self, cls) -> Any:
        functools.update_wrapper(self, cls)
        cls.url = self.url

        def wrapper(*args: Any, **kwds: Any):
            return cls(*args, **kwds)
        
        return wrapper

def test_url(url):
    def wrapper_class(cls):
        cls.test_url = url

        @functools.wraps(cls)
        def wrapper(*args, **kwargs):
            return cls(*args, **kwargs)

        return wrapper

    return wrapper_class

class Regex:
    def __init__(self, pattern, repl, flags) -> None:
        self.exp = re.compile(pattern, flags=flags)
        self.repl = repl
        self.flags = flags

    def sub(self, string: str):
        return self.exp.sub(self.repl, string)

@test_url("https://regex101.com/r/.../...")
class SubRegex(Regex):
    def __init__(self):
        super().__init__(r'...', r'...', re.MULTILINE | re.DOTALL)

But my problem is that when I wanns cycle on all classes in the module using this code:

def test_all_regexs(regex):
    module = importlib.import_module("...")
    print(f"Looking at {module}")
    for name, obj in inspect.getmembers(module):
        if inspect.isclass(obj):
            print(f"Class: {name}, {obj}")
        if inspect.isfunction(obj):
            print(f"Func: {name}, {obj}")

The output is always:

Func: SubRegex, <function SubRegex at ...>
Class: Regex, <class '....Regex'>
Class: TestUrl, <class '....TestUrl'>
Func: test_url, <function test_url at ...>

I can't figure out how obtain SubRegex as Class, not as Func. How can I get this?

PS: Do you have another way to don't mix application logic like regex patterns with the url I use only for documentation?

Answer 1

Your decorator shouldn't define a new function (or even a new class) to return (or even a new class). It should simply update cls in-place, then return cls itself.

def test_url(url):
    def wrapper(cls):
        cls.test_url = url
        return cls 
    return wrapper