Here is an issue covering PEP 3155 implementation. Hopefully a "review" link will appear in front of the hg repo URL.

I just have a comment: "XXX" should be replaced in "Python 3.3a0  3200 XXX".

Nothing to say; waiting for a doc update.

New patch addressing Benjamin's and Victor's comments.

Ah, PyFunction_NewWithQualName is now public.

Why an upper P in "PyFunction_NewWithQualName"? If you use an upper P, it should use an underscore in Python: __qual_name__ to be consistent. So I suggest to change the C name :-) PyFunction_NewWithQualname or PyFunction_NewWithQualifiedName. I don't have a preference between these two choices.

> Why an upper P in "PyFunction_NewWithQualName"? If you use an upper P,
> it should use an underscore in Python: __qual_name__ to be consistent.

__getattr__ / PyObject_GetAttr.

Doc patch looks good.

Is it intended that pickle will use __qualname__?

Yes, but that can be a separate patch - step 1 is to make the attribute available, then relevant modules can subsequently be updated to use it as appropriate.

> Is it intended that pickle will use __qualname__?

That's part of the plan for PEP 3154, yes.

New changeset e1dbc72bd97f by Antoine Pitrou in branch 'default':
PEP 3155 / issue #13448: Qualified name for classes and functions.
http://hg.python.org/cpython/rev/e1dbc72bd97f

Now committed together with docs and a what's new entry. Thanks for the reviews!

There are some callables which are missing __qualname__:

  method_descriptor
  wrapper_descriptor
  builtin_function_or_method

For the descriptors, at least, obj.__qualname__ should be equivalent to

  obj.__objclass__.__qualname__ + '.' + obj.__name__

Were these overlooked?

  PS C:\Repos\cpython> .\PCbuild\python_d
  Python 3.3.0a0 (default, Nov 25 2011, 22:14:28) [MSC v.1500 32 bit (Intel)] on win32
  Type "help", "copyright", "credits" or "license" for more information.
  >>> import pickle
  [66213 refs]
  >>> attribs = ('__class__', '__name__', '__qualname__')
  [66220 refs]
  >>> for o in (pickle.Pickler, pickle.Pickler.dump, object.__init__, min):
  ...   print([getattr(o, a, None) for a in attribs])
  ...
  [<class 'type'>, 'Pickler', 'Pickler']
  [<class 'method_descriptor'>, 'dump', None]
  [<class 'wrapper_descriptor'>, '__init__', None]
  [<class 'builtin_function_or_method'>, 'min', None]
  [66265 refs]

Also I notice that bound methods have a misleading __qualname__:

  >>> class A:
  ...   def f(self): pass
  ...
  [66348 refs]
  >>> A().f.__qualname__
  'A.f'

Maybe this should be 'A().f' instead.

For builtin_function_or_method it seems obj.__qualname__ should be

  obj.__self__.__qualname__ + '.' + obj.__name__

> There are some callables which are missing __qualname__:
> 
>   method_descriptor
>   wrapper_descriptor
>   builtin_function_or_method
> 
> For the descriptors, at least, obj.__qualname__ should be equivalent to
> 
>   obj.__objclass__.__qualname__ + '.' + obj.__name__
> 
> Were these overlooked?

Indeed, they were overlooked. Due to the way they are instantiated,
though, it would be quite a bit harder to devise a __qualname__ for
them.

> Also I notice that bound methods have a misleading __qualname__:
> 
>   >>> class A:
>   ...   def f(self): pass
>   ...
>   [66348 refs]
>   >>> A().f.__qualname__
>   'A.f'
> 
> Maybe this should be 'A().f' instead.

I am a bit surprised that this works at all. Apparently attribute
lookups are redirected to the underlying function.

I am evaluating the use of "__qualname__" in my dtrace probes (issue #13405) and I see things like this:

"""
>>> def a() :
...   class b() :
...     pass
...   return b()
... 
>>> c=a()
>>> c
<__main__.a.<locals>.b object at 0xfe37f3ac>
>>> c.__qualname__
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AttributeError: 'b' object has no attribute '__qualname__'
>>> a
<function a at 0xfe3800bc>
>>> a.__qualname__
'a'
"""

I guess the class should have a __qualname__ too, haven't it?

No, it's only class objects that have __name__ and __qualname__, not class instances.

Doc/library/dis.rst wasn't updated for the extra pop introduced to MAKE_CLOSURE opcode.