python-pymongo fails to build with Python 3.14.0a6.

ImportError while loading conftest '/builddir/build/BUILD/python-pymongo-4.9.1-build/mongo-python-driver-4.9.1/test/conftest.py'.
test/__init__.py:1131: in <module>
    class IntegrationTest(PyMongoTestCase):
test/__init__.py:1153: in IntegrationTest
    @client_context.require_connection
test/__init__.py:502: in require_connection
    return self._require(
test/__init__.py:491: in _require
    return make_wrapper(func)
test/__init__.py:455: in make_wrapper
    if iscoroutinefunction(f):
/usr/lib64/python3.14/asyncio/coroutines.py:23: in iscoroutinefunction
    warnings._deprecated("asyncio.iscoroutinefunction",
/usr/lib64/python3.14/warnings.py:677: in _deprecated
    warn(msg, DeprecationWarning, stacklevel=3)
E   DeprecationWarning: 'asyncio.iscoroutinefunction' is deprecated and slated for removal in Python 3.16; use inspect.iscoroutinefunction() instead


When this is mitigated, another DeprecationWarning is all over the place: event_loop_policy fixture directly uses asyncio.get_event_loop_policy().

___________ ERROR at setup of TestServerApi.test_command_options_txn ___________

    @pytest.fixture(scope="session")
    def event_loop_policy():
        # The default asyncio loop implementation on Windows
        # has issues with sharing sockets across loops (https://github.com/python/cpython/issues/122240)
        # We explicitly use a different loop implementation here to prevent that issue
        if sys.platform == "win32":
            # Needed for Python 3.8.
            asyncio.set_event_loop_policy(asyncio.WindowsSelectorEventLoopPolicy())
            return asyncio.WindowsSelectorEventLoopPolicy()  # type: ignore[attr-defined]
    
>       return asyncio.get_event_loop_policy()

test/conftest.py:22: 
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 
/usr/lib64/python3.14/asyncio/events.py:806: in get_event_loop_policy
    warnings._deprecated('asyncio.get_event_loop_policy', remove=(3, 16))
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 

name = 'asyncio.get_event_loop_policy'
message = '{name!r} is deprecated and slated for removal in Python {remove}'

    def _deprecated(name, message=_DEPRECATED_MSG, *, remove, _version=sys.version_info):
        """Warn that *name* is deprecated or should be removed.
    
        RuntimeError is raised if *remove* specifies a major/minor tuple older than
        the current Python version or the same version but past the alpha.
    
        The *message* argument is formatted with *name* and *remove* as a Python
        version tuple (e.g. (3, 11)).
    
        """
        remove_formatted = f"{remove[0]}.{remove[1]}"
        if (_version[:2] > remove) or (_version[:2] == remove and _version[3] != "alpha"):
            msg = f"{name!r} was slated for removal after Python {remove_formatted} alpha"
            raise RuntimeError(msg)
        else:
            msg = message.format(name=name, remove=remove_formatted)
>           warn(msg, DeprecationWarning, stacklevel=3)
E           DeprecationWarning: 'asyncio.get_event_loop_policy' is deprecated and slated for removal in Python 3.16

According to https://docs.python.org/dev/whatsnew/3.14.html#id3

asyncio policy system is deprecated and will be removed in Python 3.16. In particular, the following classes and functions are deprecated:
asyncio.AbstractEventLoopPolicy
asyncio.DefaultEventLoopPolicy
asyncio.WindowsSelectorEventLoopPolicy
asyncio.WindowsProactorEventLoopPolicy
asyncio.get_event_loop_policy()
asyncio.set_event_loop_policy()
asyncio.set_event_loop()
Users should use asyncio.run() or asyncio.Runner with loop_factory to use the desired event loop implementation.)


https://docs.python.org/3.14/whatsnew/3.14.html

For the build logs, see:
https://copr-be.cloud.fedoraproject.org/results/@python/python3.14/fedora-rawhide-x86_64/08837401-python-pymongo/

For all our attempts to build python-pymongo with Python 3.14, see:
https://copr.fedorainfracloud.org/coprs/g/python/python3.14/package/python-pymongo/

Testing and mass rebuild of packages is happening in copr.
You can follow these instructions to test locally in mock if your package builds with Python 3.14:
https://copr.fedorainfracloud.org/coprs/g/python/python3.14/

Let us know here if you have any questions.

Python 3.14 is planned to be included in Fedora 43.
To make that update smoother, we're building Fedora packages with all pre-releases of Python 3.14.
A build failure prevents us from testing all dependent packages (transitive [Build]Requires),
so if this package is required a lot, it's important for us to get it fixed soon.

We'd appreciate help from the people who know this package best,
but if you don't want to work on this now, let us know so we can try to work around it on our side.