def port(self, portNumber, factory, interface):
"""
Create, start, and return a new L{Port}, also tracking it so it can
be stopped in the test tear down.
"""
p = Port(portNumber, factory, interface=interface)
p.startListening()
self.ports.append(p)
return p
def test_connectionLostFailed(self):
"""
L{Port.stopListening} returns a L{Deferred} which errbacks if
L{Port.connectionLost} raises an exception.
"""
port = Port(12345, ServerFactory())
port.connected = True
port.connectionLost = lambda reason: 1 // 0
return self.assertFailure(port.stopListening(), ZeroDivisionError)
