'Test a failure in getDirectory method.
The behaviour should be the same as PWD.'

def test_failedGetDirectory(self):

    self._testLogin()
    d = self.client.getDirectory()
    self.assertFailure(d, ftp.CommandFailed)
    self.assertEqual(self.transport.value(), 'PWD\r\n')
    self.client.lineReceived('550    /bar/baz:    No    such    file    or    directory')
    return d
