def test_connections(self):
asm = Assembly()
asm.add('dummy1',Dummy())
asm.add('dummy2',Dummy())
asm.add('bcast',Broadcaster(['x']))
asm.connect('dummy1.x','bcast.x_in')
asm.connect('bcast.x','dummy2.y')
self.assertEqual(set(asm.list_connections()),set([('dummy1.x', 'bcast.x_in'), ('bcast.x', 'dummy2.y')]))
asm.bcast.names = ['z']
self.assertEqual(asm.list_connections(),[])
