def _runTest(self, clientProto, serverProto, clientIsServer=False):
        self.clientProto = clientProto
        cf = self.clientFactory = protocol.ClientFactory()
        cf.protocol = lambda: clientProto
        if clientIsServer:
            cf.server = False
        else:
            cf.client = True

        self.serverProto = serverProto
        sf = self.serverFactory = protocol.ServerFactory()
        sf.protocol = lambda: serverProto
        if clientIsServer:
            sf.client = False
        else:
            sf.server = True

        port = reactor.listenTCP(0, sf, interface="127.0.0.1")
        self.addCleanup(port.stopListening)

        reactor.connectTCP('127.0.0.1', port.getHost().port, cf)

        return defer.gatherResults([clientProto.deferred, serverProto.deferred])
Credentials file 'foobar' cannot be found in default subdir.
dataset/ETHPy150Open twisted/twisted/twisted/test/test_ssl.py/TLSTests._runTest--crossover with--dataset/ETHPy150Open nltk/nltk/nltk/test/unit/test_twitter_auth.py/TestCredentials.test_missingfile2