Fix test_windows_event_loop_policy for Python 3.14 compatibility#251
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asyncio.WindowsSelectorEventLoopPolicy is a lazily-resolved deprecated alias on non-Windows platforms. On Python 3.14, that resolver raises NameError instead of AttributeError when accessed off Windows, and mock.patch(..., create=True) snapshots the original value via getattr(target, name, DEFAULT) before applying the patch - a call that doesn't catch NameError, so it blew up before the patch even took effect. Set/restore the attribute directly instead, sidestepping that getattr call. Verified against both Python 3.12 and 3.14. Signed-off-by: chris hay <chris.hay@uk.ibm.com>
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Summary
Prerequisite for #221 (Python 3.14 bump). `test_windows_event_loop_policy` fails on 3.14 with a `NameError` from deep inside `asyncio`'s own module `getattr`:
`asyncio.WindowsSelectorEventLoopPolicy` is a lazily-resolved deprecated alias on non-Windows platforms. On Python 3.14, that resolver raises `NameError` instead of `AttributeError` when accessed off Windows (the backing `windows_events` submodule is only imported on win32). `mock.patch(..., create=True)` snapshots the original value via `getattr(target, name, DEFAULT)` before applying the patch, and that call doesn't catch `NameError` — so it blows up before the patch is even applied. This isn't platform-specific to my machine; it reproduces the same way on Linux CI runners.
Fixed by setting/restoring the attribute directly instead of going through `mock.patch`, sidestepping the problematic `getattr` call entirely.
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