MagicStack / MagicStack/uvloop

`asyncio.get_event_loop` raises error instead of spawning new loop when no loop is running.

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Cython
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Description

>>> import uvloop, asyncio
>>> asyncio.get_event_loop()
<_UnixSelectorEventLoop running=False closed=False debug=False>
>>> uvloop.install()
>>> asyncio.get_event_loop()
Traceback (most recent call last):
  File "<python-input-4>", line 1, in <module>
    asyncio.get_event_loop()
    ~~~~~~~~~~~~~~~~~~~~~~^^
  File "/usr/local/lib/python3.13/site-packages/uvloop/__init__.py", line 206, in get_event_loop
    raise RuntimeError(
    ...<2 lines>...
    )
RuntimeError: There is no current event loop in thread 'MainThread'.
>>>

As you can see in the snippet above when run on un-patched asyncio it's returning a new loop. But uvloop raises error because of the method override which was not there in previous version inheriting the original new loop spawning function.

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Research direction

Reproduce the Python snippet with uvloop installed, then inspect the get_event_loop override in uvloop/init.py around the linked method. Compare its behavior with unpatched asyncio; the issue is done when calling asyncio.get_event_loop() without a running loop has the expected behavior in both cases.

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Assessment

Tech stack
python
Domain
backend
Issue type
Bug
Difficulty
2/5
Estimated time
1-3 hours
Activity status
Quiet
Clarity
Clearly specified
Newbie friendliness
68/100

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