'L{_WrappingProtocol.fileDescriptorReceived} calls the wrapped
protocol\'s C{fileDescriptorReceived} method.'

def test_wrappedProtocolFileDescriptorReceived(self):

    wrappedProtocol = TestFileDescriptorReceiverProtocol()
    wrapper = endpoints._WrappingProtocol(defer.Deferred(), wrappedProtocol)
    wrapper.makeConnection(StringTransport())
    wrapper.fileDescriptorReceived(42)
    self.assertEqual(wrappedProtocol.receivedDescriptors, [42])
