def test_channel_receiver_callback(self): 

       l = []

       #channel = self.gw.newchannel(receiver=l.append)

       channel = self.gw.remote_exec(source='''

               channel.send(42)

               channel.send(13)

               channel.send(channel.gateway.newchannel())

               ''') 

       channel.setcallback(callback=l.append)

       py.test.raises(IOError, channel.receive)

->     channel.waitclose(TESTTIMEOUT)

       assert len(l) == 3

       assert l[:2] == [42,13]

       assert isinstance(l[2], channel.__class__)