def test_callback(self):

       dest = self.dest1

       source = self.source

       source.ensure("existant").write("a" * 100)

       source.ensure("existant2").write("a" * 10)

       total = {}

       def callback(cmd, lgt, channel):

           total[(cmd, lgt)] = True

       rsync = RSync(source, callback=callback)

       #rsync = RSync()

       rsync.add_target(gw, dest)

->     rsync.send()

       assert total == {("list", 110):True, ("ack", 100):True, ("ack", 10):True}