_test_multiprocessing.py 文件源码

def test_stderr_flush(self):
        # sys.stderr is flushed at process shutdown (issue #13812)
        if self.TYPE == "threads":
            self.skipTest('test not appropriate for {}'.format(self.TYPE))

        testfn = test.support.TESTFN
        self.addCleanup(test.support.unlink, testfn)
        proc = self.Process(target=self._test_stderr_flush, args=(testfn,))
        proc.start()
        proc.join()
        with open(testfn, 'r') as f:
            err = f.read()
            # The whole traceback was printed
            self.assertIn("ZeroDivisionError", err)
            self.assertIn("test_multiprocessing.py", err)
            self.assertIn("1/0 # MARKER", err)