[Python-Dev] [Python-checkins] r53997 - in python/trunk: Lib/test/crashers/modify_dict_attr.py Lib/test/test_descr.py Objects/typeobject.c (original) (raw)

Armin Rigo arigo at tunes.org
Fri Mar 9 21:45:17 CET 2007

Hi Jeremy,

On Tue, Feb 27, 2007 at 07:29:50PM +0100, jeremy.hylton wrote:

Removed: python/trunk/Lib/test/crashers/modifydictattr.py Modified: python/trunk/Lib/test/testdescr.py python/trunk/Objects/typeobject.c Log: Add checking for a number of metaclass error conditions.

This check-in looks highly suspicious to me. It doesn't solve the problem it set out to solve, which is the modify_dict_attr crasher - see the slightly modified modify_dict_attr that I re-checked in (Lib/test/crashers/). Instead it adds more of the obscure undocumented rules about what kind of inheritence is allowed or not. We already have cases like:

class X(str): pass
class Y(str): pass
class Z(X, Y): pass

which are forbidden for no user-discernable reason. I don't think that forbidding:

class X(Y, type): pass

is going to help clarity there.

The problem with modify_dict_attr is at a different level; if needed I can elaborate on the following comment from the SF tracker:

"""A proposed fix [for modify_dict_attr]: the __dict__ descriptor of
user-defined classes should verify if there is another __dict__
descriptor along the solid path of the type (i.e. following "tp_base"
pointers).  If so, it should delegate to it."""

A bientot,

Armin.

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