Loop.call_later(0) and Loop.call_later(-1) return a uvloop.loop.Handle and not an asyncio.TimerHandle

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#482 opened on Jul 20, 2022 2 comments 0 reactions 0 assignees View on GitHub

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Assessment

Difficulty: 2/5
Estimated time: 1-3 hours
Newbie friendliness: 45/100

Issue type: Bug
Clarity: Clearly specified
Activity status: Stale
Tech stack: python
Domain: backend

Research direction

Start in uvloop/loop.pyx at lines 1327-1328 and compare the behavior of Loop.call_later(0) and Loop.call_later(-1) with vanilla asyncio. Done means both uvloop calls return an asyncio.TimerHandle rather than a uvloop.loop.Handle, including when PYTHONASYNCIODEBUG is enabled.

Written by the indexing model from the issue text.

Description

uvloop version: master
Python version: 3.10
Platform: ubuntu
Can you reproduce the bug with PYTHONASYNCIODEBUG in env?: yes
Does uvloop behave differently from vanilla asyncio? How?: yes

Python 3.10.5 (main, Jun 11 2022, 16:53:24) [GCC 9.4.0] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> import asyncio
>>> import uvloop
>>> uvloop.new_event_loop().call_later(-1, lambda: None)
<Handle <lambda>>
>>> asyncio.new_event_loop().call_later(-1, lambda: None)
<TimerHandle when=79332.145640902 <lambda>() at <stdin>:1>
>>>

the bug is here:
https://github.com/MagicStack/uvloop/blob/5926386f81ea49903db9d5095058787ed91cff3d/uvloop/loop.pyx#L1327-L1328

Dominant language: Cython
Stars: 11.9k
Forks: 615
PR merge metrics: No merged PRs in 30d

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