def test_emptyChildUnicodeParent(self):
        """
        The C{u''} child of a L{File} which corresponds to a directory
        whose path is text is a L{DirectoryLister} that renders to a
        binary listing.

        @see: U{https://twistedmatrix.com/trac/ticket/9438}
        """
        textBase = FilePath(self.mktemp()).asTextMode()
        textBase.makedirs()
        textBase.child(u"text-file").open('w').close()
        textFile = static.File(textBase.path)

        request = DummyRequest([b''])
        child = resource.getChildForRequest(textFile, request)
        self.assertIsInstance(child, static.DirectoryLister)

        nativePath = compat.nativeString(textBase.path)
        self.assertEqual(child.path, nativePath)

        response = child.render(request)
        self.assertIsInstance(response, bytes)

        The C{u''} child of a L{File} which corresponds to a directory
        whose path is text is a L{DirectoryLister} that renders to a
        binary listing.

        @see: U{https://twistedmatrix.com/trac/ticket/9438}
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/web/test/test_static.py