list iterator `__setstate__()` differs for exhausted iterator GIL vs. non-GIL

[tom-pytel]

Or is this too pedantic?

GIL enabled:

$ ./python
Python 3.14.0a4+ (heads/main:f3980af38b, Jan 21 2025, 11:34:12) [GCC 11.4.0] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> it = iter([1]); list(it)
[1]
>>> it.__setstate__(0); list(it)
[]

GIL disabled:

$ ./python
Python 3.14.0a4+ experimental free-threading build (heads/main:f3980af38b, Jan 21 2025, 11:31:38) [GCC 11.4.0] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> it = iter([1]); list(it)
[1]
>>> it.__setstate__(0); list(it)
[1]

v3.14, current main, its a one line fix.

[eendebakpt]

@Yhg1s Your changes in #128637 might result in a similar behavior change for tuple iterators as is described here for list iterators.

[Yhg1s]

Yes, indeed. It's not difficult to fix, by the way, it just requires an extra check in the relevant __setstate__ methods. I'm not sure it's worth it.