test_threading.py 文件源码

def test_dummy_thread_after_fork(self):
        # Issue #14308: a dummy thread in the active list doesn't mess up
        # the after-fork mechanism.
        code = """if 1:
            import thread, threading, os, time

            def background_thread(evt):
                # Creates and registers the _DummyThread instance
                threading.current_thread()
                evt.set()
                time.sleep(10)

            evt = threading.Event()
            thread.start_new_thread(background_thread, (evt,))
            evt.wait()
            assert threading.active_count() == 2, threading.active_count()
            if os.fork() == 0:
                assert threading.active_count() == 1, threading.active_count()
                os._exit(0)
            else:
                os.wait()
        """
        _, out, err = assert_python_ok("-c", code)
        self.assertEqual(out, '')
        self.assertEqual(err, '')