[Pythonmac-SIG] PyObjC + AEInstallEventHandler crash?

[Bob Ippolito]

> Trying to figure why the following test app crashes when a 'testtest'
> Apple event is sent to it:
>
> ------------------------------------------------------------
> # cocoatest.py
>
> from PyObjCTools import AppHelper
> from Carbon.AE import AEInstallEventHandler
>
> AEInstallEventHandler('test', 'test', lambda evt, res:0)
>
> AppHelper.runEventLoop()
>
> ------------------------------------------------------------
>
> Additional notes: the test app doesn't crash when
> AppKit.NSAppleEventManager is used to install the event handler function,
> nor when CarbonEvt is used instead of PyObjC.
>
> I'm getting a similar crash in some CarbonX.OSA code within a PyObjC-based
> app and reckon identifying what's causing the test app to crash will help
> me solve the problem there. Any ideas as to the cause, suggestions where
> to look, how to debug it more effectively, etc. would be a big help as
> I've been stuck on this for more than a day now and have only just fitted
> a new laptop case after the last temper tantrum. :p

My guess is that there's a refcount or GIL bug in
Carbon.AE.AEInstallEventHandler.  I'd use NSAppleEventManager... I've used
it before and it works just fine.

    def initializeAsynchronousAppleEvents(self):
        aem = NSAppleEventManager.sharedAppleEventManager()
        aem.setEventHandler_andSelector_forEventClass_andEventID_(
            self,
            'handleAppleEvent:withReplyEvent:',
            struct.unpack('>i', 'aevt')[0],
            struct.unpack('>i', 'ansr')[0])

    def handleAppleEvent_withReplyEvent_(self, event, replyEvent):
        reply = event.aeDesc()
        ...

-bob