def test_getLogObserverDefaultFile(self):
        """
        When daemonized and C{logfile} is empty, the observer returned by
        L{UnixAppLogger._getLogObserver} points at C{twistd.log} in the current
        directory.
        """
        logFiles = _patchTextFileLogObserver(self.patch)
        logger = UnixAppLogger({"logfile": "", "nodaemon": False})
        logger._getLogObserver()

        self.assertEqual(len(logFiles), 1)
        self.assertEqual(logFiles[0].path, os.path.abspath("twistd.log"))

        When daemonized and C{logfile} is empty, the observer returned by
        L{UnixAppLogger._getLogObserver} points at C{twistd.log} in the current
        directory.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/test/test_twistd.py