Add the default attributes to functools.partial

[JensHeinrich]

Feature or enhancement

Add __qualname__ and __name__ to functools.partial

Pitch

Even an anonymous lambda function gets a __qualname__ or rather __name__ of <lambda> and partial should behave in the same way.

Previous discussion

This has been previously discussed in #78656, but as lambda-functions are named since before ccd1921 363ac7d a similiar behavior of using <partial> as the name should have been suggested in the last discussion already.

[sobolevn]

Why do you need this? There are other callable objects that can miss __qualname__:

>>> class MyCallable:
...     def __call__(self, *args, **kwargs):
...         print('whatever')
... 
>>> MyCallable()()
whatever
>>> MyCallable().__qualname__
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AttributeError: 'MyCallable' object has no attribute '__qualname__'

What is so special about partial?

Isn't getattr(obj, '__qualname__', '<default name>') enough?

[JensHeinrich]

That's a valid workaround for the usecase that prompted this ticket, but I still feel it wouldn't hurt to just use <partial> as a __name__ attribute

[sobolevn]

@JensHeinrich the problem with adding __name__ and __qualname__ attributes to partial is that it is not enough. There are also __annotations__ and __code__ attributes (and others) that people might assume all callables have. So, it is either full compatibility with the callable API or just __call__ as it is now.

I prefer the status quo :)
And based on previous descussion I will close this ticket.

I hope my explanation helped! Thanks for the report.

[JensHeinrich]

I do get the reasoning, but I will mention the discussion in #91002 as I see those points are related. This hopefully helps future me or other people researching it.