[PyQt] Re: New bug in SIP

[Giovanni Bajo]

On 5/30/2008 3:30 PM, Phil Thompson wrote:
> On Friday 30 May 2008 1:05:11 pm Giovanni Bajo wrote:
>> On 5/30/2008 12:32 PM, Phil Thompson wrote:
>>> On Wednesday 28 May 2008 3:39:11 pm Giovanni Bajo wrote:
>>>> Hi Phil,
>>>>
>>>> I found a new bug in SIP (it used to work with a SIP from September
>>>> 2007).
>>>>
>>>> If you declare a class with a single constructor, you write %MethodCode
>>>> for that constructor, and you make it raise an exception (PyErr_Format)
>>>> and set sipIsErr=1, the exception is not propagated to Python: it gets
>>>> "swallowed" and changed into an AttributeError which says "... is a
>>>> private method".
>>>>
>>>> Basically, this code in sipWrapper_init, line 7173:
>>>>
>>>>              	/*
>>>>              	 * If the arguments were parsed without error then assume
>>>> an * exception has already been raised for why the instance * wasn't
>>>> created.
>>>>              	 */
>>>>                  if (pstate == PARSE_OK)
>>>>                      argsparsed = PARSE_RAISED;
>>>>
>>>>
>>>> is not executed, because pstate was already mutated a few lines above:
>>>>
>>>>
>>>>              /*
>>>>               * If the parse was successful but no C/C++ object was
>>>> created then
>>>>               * we assume that handwritten code decided after the parse
>>>> that * it didn't want to handle the signature.
>>>>               */
>>>>              if (pstate == PARSE_OK)
>>>>                  pstate = PARSE_TYPE;
>>>>
>>>>
>>>> I was wondering if it should check "argsparsed == PARSE_OK" (at line
>>>> 7173) instead of "pstate == PARSE_OK".
>>>>
>>>> Thanks!
>>> I think the bug is that the earlier code should be...
>>>
>>>     if (pstate == PARSE_OK)
>>>         pstate = argsparsed = PARSE_TYPE;
>> This changes the exception into a TypeError (eg: "argument 1 has an
>> invalid type"), but it still mask the original exception that was raised
>> in the %MethodCode.
> 
> Hmm - I need to think about this a bit more. It's all related to the QVariant 
> support for Python objects.

IMHO sip is getting to a complexity point where a testsuite might help 
in sorting out these bugs while you are developing new code and/or 
refactoring. If you are interested in having one, I can help 
contributing the infrastructure for it.
-- 
Giovanni Bajo
Develer S.r.l.
http://www.develer.com