homepage

I noticed a change in the behaviour of __import__() between 3.2 and 3.3. It looks like in 3.2 __import__() does a Py2-style combo relative/absolute import. Here's a minimal test case:
$ ls foo
bar.py __init__.py __pycache__
$ cat foo/__init__.py
__import__('bar', globals(), locals())
$ python3.3 -c "import foo"
Traceback (most recent call last):
 File "<string>", line 1, in <module>
 File "./foo/__init__.py", line 1, in <module>
 __import__('bar', globals(), locals())
ImportError: No module named 'bar'
$ python3.2 -c "import foo"
$
I believe that 3.3 is correct and that 3.2 is wrong but can't be changed now, so I suppose that 3.2 should just document the actual behaviour of __import__() and 3.3 should document the change. 
(The context is that I encountered issue 15434. This looks related, but I'm not sure it is.)

See issue14592 (particularly msg158466).

The specific bug is that, in 3.2, the claimed default (level=0) is not accurate: the default is actually (level=-1), as it was in 2.x. The import statement passes level=0 explicitly (as it does in 2.x when "from __future__ import absolute_import" is in effect).
The docstring in 3.2 is accurate, the prose documentation is incorrect.
In 3.3, the docstring is currently wrong, but the prose documentation is correct. However, it should have a "versionchanged: 3.3" not added, indicating that the default import level has finally been brought into compliance with the documentation.

s/not added/note added/

So should 3.2 be changed to adjust the default value to match the documentation?

On Jul 29, 2012 5:58 AM, "Martin v. Löwis" <report@bugs.python.org> wrote:
>
>
> Martin v. Löwis added the comment:
>
> So should 3.2 be changed to adjust the default value to match the
documentation?
It is probably safe to do so.
-brett
>
> ----------
> nosy: +loewis
>
> _______________________________________
> Python tracker <report@bugs.python.org>
> <http://bugs.python.org/issue15482>
> _______________________________________

I just realized my reply was unclear; I meant changing Doc/library/functions.rst, not the code.
And 3.3 already has a versionchanged note about no longer accepting negative indexes, but I will update it to mention the new default as well explicitly.

New changeset 3fe01f7520e2 by Brett Cannon in branch '3.2':
Issue #15482: Properly document the default 'level' parameter for
http://hg.python.org/cpython/rev/3fe01f7520e2
New changeset 05bec2e78a5c by Brett Cannon in branch 'default':
Issue #15482: Merge 78449:3fe01f7520e2 with a minor clarification.
http://hg.python.org/cpython/rev/05bec2e78a5c