classification
Title: asyncio.wait_for does not cancel running tasks in the correct fashion
Type: behavior Stage:
Components: asyncio Versions: Python 3.8
process
Status: open Resolution: remind
Dependencies: Superseder:
Assigned To: Nosy List: asvetlov, ofekkir, yselivanov
Priority: normal Keywords:

Created on 2021-06-10 05:55 by ofekkir, last changed 2021-06-20 05:15 by ofekkir.

Messages (2)
msg395505 - (view) Author: Ofek Kirzner (ofekkir) Date: 2021-06-10 05:55
Following https://bugs.python.org/issue32751 I think wait_for should also wait for running coroutine in case it has been cancelled.

Example code:

import asyncio


async def inner():
    try:
        print(1)
        await asyncio.sleep(3600)
        print(2)
    except asyncio.CancelledError:
        print('inner - canc')
        raise


async def outer(f):
    try:
        print('a')
        # Version 1 - This creates the expected behaviour
        # await f
        # Version 2 - This creates the reversed behaviour
        await asyncio.wait_for(f, timeout=500)
        print('b')
    except asyncio.CancelledError:
        print('outer - canc')


@pytest.mark.asyncio
async def test_t1():
    t = asyncio.create_task(outer(inner()))
    done, pending = await asyncio.wait([t], timeout=1)
    t.cancel()

    await t

------
I expect inner to be cancelled and awaited before outer is finished.
i.e., exepcted output:
1
inner - canc
outer - canc


While I get:
1
outer - canc
inner - canc
msg396162 - (view) Author: Ofek Kirzner (ofekkir) Date: 2021-06-20 05:15
Kindly reminder.
Thx :)
History
Date User Action Args
2021-06-20 05:15:37ofekkirsetresolution: remind
messages: + msg396162
2021-06-10 05:55:58ofekkircreate