`types.GenericAlias` has extra `__copy__` and `__deepcopy__` in `__dir__`

[sobolevn]

Repro:

>>> type A[X] = list[X]
>>> dir(A[int])
[..., '__copy__', '__deepcopy__', ...]

We can access all other attributes, but not __copy__ and __deepcopy__:

>>> A[int].__copy__
Traceback (most recent call last):
 File "<stdin>", line 1, in <module>
AttributeError: 'types.GenericAlias' object has no attribute '__copy__'. Did you mean: '__doc__'?

>>> A[int].__deepcopy__
Traceback (most recent call last):
 File "<stdin>", line 1, in <module>
AttributeError: 'types.GenericAlias' object has no attribute '__deepcopy__'

I am not quite sure what is the right thing to do here 🤔

Linked PRs

• gh-105487: Fix __dir__ entries of GenericAlias #138578
• [3.14] gh-105487: Fix __dir__ entries of GenericAlias (GH-138578) #138629
• [3.13] gh-105487: Fix __dir__ entries of GenericAlias (GH-138578) #138640

[hugovk]

Thanks for the fix!

[asottile-sentry]

a little late to the party but __bases__ appears to not work as well:

>>> '__bases__' in dir(list[str])
True
>>> list[str].__bases__
Traceback (most recent call last):
 File "<python-input-15>", line 1, in <module>
 list[str].__bases__
AttributeError: 'types.GenericAlias' object has no attribute '__bases__'. Did you mean: '__args__'?

[sobolevn]

Looks like the linked PR does something completely different. I created a new one.

[sobolevn]

Thanks for the report!