René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"all deprecation warnings are disabled for the whole process while new unix asyncio subprocesses are created","articleBody":"on python3.10 the following prints:\r\n\r\n```\r\npython3.10 demo.py \r\n/home/graingert/projects/cpython/demo.py:40: DeprecationWarning: demo warning\r\n  warnings.warn(\"demo warning\", DeprecationWarning)\r\n/home/graingert/projects/cpython/demo.py:48: DeprecationWarning: demo warning2\r\n  warnings.warn(\"demo warning2\", DeprecationWarning)\r\n```\r\n\r\nbut on python main it prints:\r\n\r\n```\r\n./python demo.py      \r\n/home/graingert/projects/cpython/demo.py:40: DeprecationWarning: demo warning\r\n  warnings.warn(\"demo warning\", DeprecationWarning)\r\n```\r\n\r\n```python\r\nimport sys\r\nimport threading\r\nimport asyncio\r\nimport concurrent.futures\r\nimport warnings\r\n\r\n\r\nasync def acreate_process_then_sleep(started_event, stop_event):\r\n    event = asyncio.Event()\r\n\r\n    async def create_process():\r\n        loop = asyncio.get_running_loop()\r\n        loop.call_soon(event.set)\r\n        proc = await asyncio.create_subprocess_exec(\r\n            sys.executable,\r\n            \"-c\",\r\n            \"print('hello')\",\r\n            stdin=None,\r\n            stdout=asyncio.subprocess.PIPE,\r\n            stderr=asyncio.subprocess.STDOUT,\r\n        )\r\n        await proc.communicate()\r\n\r\n    async def sleep():\r\n        await event.wait()\r\n        started_event.set()\r\n        stop_event.wait()\r\n\r\n    await asyncio.gather(create_process(), sleep())\r\n\r\n\r\ndef create_process_then_sleep(*args, **kwargs):\r\n    asyncio.run(acreate_process_then_sleep(*args, **kwargs))\r\n\r\n\r\ndef main():\r\n    with concurrent.futures.ThreadPoolExecutor() as tpe:\r\n        stop_event = threading.Event()\r\n        started_event = threading.Event()\r\n        warnings.warn(\"demo warning\", DeprecationWarning)\r\n        fut = tpe.submit(\r\n            create_process_then_sleep,\r\n            started_event=started_event,\r\n            stop_event=stop_event,\r\n        )\r\n        try:\r\n            started_event.wait()\r\n            warnings.warn(\"demo warning2\", DeprecationWarning)\r\n        finally:\r\n            stop_event.set()\r\n            fut.result()\r\n\r\n\r\nif __name__ == \"__main__\":\r\n    sys.exit(main())\r\n```\r\n\r\n_Originally posted by @graingert in https://github.com/python/cpython/pull/98215#discussion_r996426251_\r\n      ","author":{"url":"https://github.com/graingert","@type":"Person","name":"graingert"},"datePublished":"2022-10-16T11:55:24.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":7},"url":"https://github.com/98327/cpython/issues/98327"}