[Pyobjc-dev] Memory management bug using .new()

[Dirk S. <dir...@ma...>]

Hi all,

I don't think anyone ever uses this method – NSObject.new() – anymore,  
but in case someone does: I just ran into a reproducable problem with  
it.

When you create a new cocoa object within an instance method of a  
Cocoa class implemented in Python, normally that fresh object is  
released when the scope dissapears. (that is, when you're not storing  
a reference to it in an attribute that exists outside of the method's  
scope).

e.g.:

class MyAmazingViewController(NSViewController):
     def animate(self):
         animation = NSViewAnimation.alloc().init()
         # insert code to create an array/list of NSDictionaries  
describing the animations
          
animation.setViewAnimations_(theAboveMentionedHypotheticalArray)
         animation.setDuration_(5.0)
         animation.setAnimationBlockingMode_(NSAnimationNonblocking)
         animation.startAnimation()

( if the spaces got stripped from my example somehow, snippet also  
pasted here: http://pastie.org/516369 )

After control returns from the "animate" method, and after the  
animation is done, it is automatically released.

However if you replace "NSViewAnimation.alloc().init()", with  
"NSViewAnimation.new()", the animation is not automatically released.   
Consequentially, any views or windows included in the dictionaries  
that form the viewAnimations array are also retained, causing quite a  
significant leak.

Juding from the NSObject class docs, calling "new()" on a class should  
do exactly the same thing as "alloc().init()", but PyObjC doesn't seem  
to treat it the same way.

http://tinyurl.com/nsobject-new

Can anyone enlighten me whether this is a bug, a feature, or simply  
something I'm misunderstanding?

Thanks!
- Dirk