Add class decorator to inherit parent docs-CodePudding

I am trying to add a util to my package where a subclass will inherit the superclasses's docstring. Here is what I set up so far.

from functools import wraps
import typing as t


def inherit_parent_docs(klass):
    @wraps(klass)
    def inside(*args: t.Any, **kwargs: t.Any):
        parent_doc = B.__bases__[0].__doc__
        klass.__doc__  = parent_doc
        klass_out = klass(*args, **kwargs)
        return klass_out

    return inside

class A:
    """super"""

@inherit_parent_docs
class B(A):
    """sub"""
    def __init__(self):
        pass

However, this does not work because it says B doesn't have bases dunder because it thinks its a function. And I checked, strangely enough, type(B) is function. Also I tried wrapping the constructor, but then the docstring is only updated when instantiated.

I feel like I am missing something obvious here...

CodePudding user response：

So that is what decoration does. It assigned the function, inside to B.

So when you

@inherit_parent_docs
class B(A):
    ...

That is syntactic sugar for:

class B(A):
    ...
B = inherit_parent_docs(B)

Note, you could just not return a wrapper. Return the Klass after you've modified it:

def inherit_parent_docs(klass):
    doc = klass.__doc__
    parent_doc = klass.__bases__[0].__doc__
    klass.__doc__ = f"{doc}\n{parent_doc}\n"
    return klass