| 9 | |
| 10 | |
| 11 | class Observable(object): |
| 12 | def __init__(self): |
| 13 | self.observers = [] |
| 14 | |
| 15 | def add_observer(self, observer): |
| 16 | sys.stdout.write( 'observer %s\n' % (observer,)) |
| 17 | ref = weakref.ref(observer) |
| 18 | self.observers.append(ref) |
| 19 | sys.stdout.write('weakref: %s\n' % (ref(),)) |
| 20 | |
| 21 | def Notify(self): |
| 22 | for o in self.observers: |
| 23 | o = o() |
| 24 | |
| 25 | |
| 26 | try: |
| 27 | import gc |
| 28 | except ImportError: |
| 29 | o = None #some jython does not have gc, so, there's no sense testing this in it |
| 30 | else: |
| 31 | try: |
| 32 | gc.get_referrers(o) |
| 33 | except: |
| 34 | o = None #jython and ironpython do not have get_referrers |
| 35 | |
| 36 | if o is not None: |
| 37 | sys.stdout.write('still observing %s\n' % (o,)) |
| 38 | sys.stdout.write('number of referrers: %s\n' % len(gc.get_referrers(o))) |
| 39 | frame = gc.get_referrers(o)[0] |
| 40 | frame_referrers = gc.get_referrers(frame) |
| 41 | sys.stdout.write('frame referrer %s\n' % (frame_referrers,)) |
| 42 | referrers1 = gc.get_referrers(frame_referrers[1]) |
| 43 | sys.stdout.write('%s\n' % (referrers1,)) |
| 44 | sys.stderr.write('TEST FAILED: The observer should have died, even when running in debug\n') |
| 45 | else: |
| 46 | sys.stdout.write('TEST SUCEEDED: observer died\n') |
| 47 | |
| 48 | sys.stdout.flush() |
| 49 | sys.stderr.flush() |
| 50 | |
| 51 | class Observer(object): |
| 52 | pass |