def test_saveOnlyImage(self):
        """
        Passing an empty string for --dot-directory/-d disables saving dot
        files.
        """
        for arg in ('--dot-directory', '-d'):
            self.digraphRecorder.reset()
            self.collectedOutput = []
            self.tool(argv=[self.fakeFQPN, arg, ''])

            self.assertFalse(any("dot" in line
                                 for line in self.collectedOutput))

            self.assertEqual(len(self.digraphRecorder.renderCalls), 1)
            (call,) = self.digraphRecorder.renderCalls
            self.assertEqual("{}.dot".format(self.fakeFQPN),
                             call['filename'])
            self.assertTrue(call['cleanup'])

            self.assertFalse(self.digraphRecorder.saveCalls)

        Passing an empty string for --dot-directory/-d disables saving dot
        files.
        
stackoverflow/venv/lib/python3.6/site-packages/automat/_test/test_visualize.py