[ python-Bugs-1510580 ] Setting category fails with -W switch

[SourceForge.net]

Bugs item #1510580, was opened at 2006-06-22 05:20
Message generated for change (Comment added) made by bcannon
You can respond by visiting: 
https://sourceforge.net/tracker/?func=detail&atid=105470&aid=1510580&group_id=5470

Please note that this message will contain a full copy of the comment thread,
including the initial issue submission, for this request,
not just the latest update.
Category: Python Library
Group: Python 2.5
Status: Open
Resolution: None
Priority: 5
Submitted By: A.M. Kuchling (akuchling)
Assigned to: Brett Cannon (bcannon)
Summary: Setting category fails with -W switch

Initial Comment:
This command reports an "invalid warning category"
error, but it shouldn't.

./python -W'ignore:Not importing directory:ImportWarning'

I think the change to new-style exceptions exposed this
problem.  warnings.py contains the following code to
trigger this error:

    if (not isinstance(cat, types.ClassType) or
        not issubclass(cat, Warning)):
        raise _OptionError("invalid warning category:
%r" % (category,))

The new-style exceptions mean that the first
isinstance() now returns False.   I think there may be
two fixes needed.  First, I think it should be
"isinstance(cat, types.ClassType) or isinstance(cat,
type)".

Second issue: hould the warnings.py code use "and"
instead of "or"?  Surely if issubclass(cat, Warning) is
True, the category is certainly OK; no?

----------------------------------------------------------------------

>Comment By: Brett Cannon (bcannon)
Date: 2006-06-22 09:05

Message:
Logged In: YES 
user_id=357491

Well, the docs for warnings
(http://docs.python.org/dev/lib/warning-categories.html) say
that a category must subclass Warning.  So I removed the
ClassType check entirely, and that causes test_exceptions to
segfault.  Lovely.

I will try to look at this Friday.

----------------------------------------------------------------------

Comment By: A.M. Kuchling (akuchling)
Date: 2006-06-22 06:50

Message:
Logged In: YES 
user_id=11375

Once the problem is fixed, the attached patch adds some
tests for warning parsing.

----------------------------------------------------------------------

You can respond by visiting: 
https://sourceforge.net/tracker/?func=detail&atid=105470&aid=1510580&group_id=5470