[3.9] bpo-44815: Always show deprecation in asyncio.gather/sleep() by Dreamsorcerer · Pull Request #27569 · python/cpython

Dreamsorcerer

I think this has introduced an unavoidable deprecation warning in BaseEventLoop.create_server(..., start_serving=True), which is the default value of start_serving:

https://github.com/python/cpython/blob/v3.9.7/Lib/asyncio/base_events.py#L1514-L1518

        if start_serving:
            server._start_serving()
            # Skip one loop iteration so that all 'loop.add_reader'
            # go through.
            await tasks.sleep(0, loop=self)

It also appears to affect Server.start_serving, which does the same thing, and from a brief glance, self._loop here is not going to be None.

https://github.com/python/cpython/blob/v3.9.7/Lib/asyncio/base_events.py#L349-L353

    async def start_serving(self):
        self._start_serving()
        # Skip one loop iteration so that all 'loop.add_reader'
        # go through.
        await tasks.sleep(0, loop=self._loop)

Edit: Late update, this new failure was also reported as https://bugs.python.org/issue45097 and fixed in 3.9.8.