Run-time failure on FreeBSD: NotImplementedError: unsupported platform

[yurivict]

When both wandb and eventlet packages are installed 'import wandb' fails in the trio code:

$ python3.11
Python 3.11.9 (main, Jul 11 2024, 01:05:32) [Clang 16.0.6 (https://github.com/llvm/llvm-project.git llvmorg-16.0.6-0-g7cbf1a on freebsd14
Type "help", "copyright", "credits" or "license" for more information.
>>> import wandb
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/local/lib/python3.11/site-packages/wandb/__init__.py", line 20, in <module>
    from wandb import sdk as wandb_sdk
  File "/usr/local/lib/python3.11/site-packages/wandb/sdk/__init__.py", line 28, in <module>
    from .wandb_init import _attach, init
  File "/usr/local/lib/python3.11/site-packages/wandb/sdk/wandb_init.py", line 32, in <module>
    from . import wandb_login, wandb_setup
  File "/usr/local/lib/python3.11/site-packages/wandb/sdk/wandb_login.py", line 25, in <module>
    from .wandb_settings import Settings
  File "/usr/local/lib/python3.11/site-packages/wandb/sdk/wandb_settings.py", line 45, in <module>
    from wandb.sdk.internal.system.env_probe_helpers import is_aws_lambda
  File "/usr/local/lib/python3.11/site-packages/wandb/sdk/internal/system/env_probe_helpers.py", line 3, in <module>
    from sentry_sdk.integrations.aws_lambda import get_lambda_bootstrap  # type: ignore
    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/site-packages/sentry_sdk/__init__.py", line 1, in <module>
    from sentry_sdk.hub import Hub, init
  File "/usr/local/lib/python3.11/site-packages/sentry_sdk/hub.py", line 9, in <module>
    from sentry_sdk.scope import Scope
  File "/usr/local/lib/python3.11/site-packages/sentry_sdk/scope.py", line 7, in <module>
    from sentry_sdk.utils import logger, capture_internal_exceptions
  File "/usr/local/lib/python3.11/site-packages/sentry_sdk/utils.py", line 1048, in <module>
    HAS_REAL_CONTEXTVARS, ContextVar = _get_contextvars()
                                       ^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/site-packages/sentry_sdk/utils.py", line 1018, in _get_contextvars
    if not _is_contextvars_broken():
           ^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/site-packages/sentry_sdk/utils.py", line 979, in _is_contextvars_broken
    from eventlet.patcher import is_monkey_patched  # type: ignore
    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/site-packages/eventlet/__init__.py", line 6, in <module>
    from eventlet import convenience
  File "/usr/local/lib/python3.11/site-packages/eventlet/convenience.py", line 7, in <module>
    from eventlet.green import socket
  File "/usr/local/lib/python3.11/site-packages/eventlet/green/socket.py", line 21, in <module>
    from eventlet.support import greendns
  File "/usr/local/lib/python3.11/site-packages/eventlet/support/greendns.py", line 78, in <module>
    setattr(dns, pkg, import_patched('dns.' + pkg))
                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/site-packages/eventlet/support/greendns.py", line 60, in import_patched
    return patcher.import_patched(module_name, **modules)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/site-packages/eventlet/patcher.py", line 132, in import_patched
    return inject(
           ^^^^^^^
  File "/usr/local/lib/python3.11/site-packages/eventlet/patcher.py", line 109, in inject
    module = __import__(module_name, {}, {}, module_name.split('.')[:-1])
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/site-packages/dns/asyncquery.py", line 32, in <module>
    import dns.quic
  File "/usr/local/lib/python3.11/site-packages/dns/quic/__init__.py", line 37, in <module>
    import trio
  File "/usr/local/lib/python3.11/site-packages/trio/__init__.py", line 23, in <module>
    from ._core import TASK_STATUS_IGNORED as TASK_STATUS_IGNORED  # isort: split
    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.11/site-packages/trio/_core/__init__.py", line 21, in <module>
    from ._local import RunVar, RunVarToken
  File "/usr/local/lib/python3.11/site-packages/trio/_core/_local.py", line 9, in <module>
    from . import _run
  File "/usr/local/lib/python3.11/site-packages/trio/_core/_run.py", line 2844, in <module>
    raise NotImplementedError("unsupported platform")
NotImplementedError: unsupported platform

The conditional in this line:

elif TYPE_CHECKING or hasattr(select, "kqueue"):

always evaluates to False because TYPE_CHECKING is always False at run-time.
Otherwise hasattr(select, "kqueue") evaluates to True.

Version: 0.26.2
Python-3.11
FreeBSD 14.1

[A5rocks]

hasattr(select, "kqueue") must be False for that to be False fwiw

[yurivict]

When I run it separately, hasattr(select, "kqueue") evaluates to True.
I don't know how can that be.

[A5rocks]

Yeah, because eventlet patches out select.kqueue. If you import trio first things should work... we should probably make the error message better.

[yurivict]

It shouldn't fail like this. This failure is very obscure. I accidentally caught this while testing wandb after having other things installed by something else.

[A5rocks]

Would this as an error message work better?: "unsupported platform or the IO primitives trio relies on are patched out" if either eventlet or gevent are detected in sys.modules?

[yurivict]

I guess this error message is okay.

The real problem seems to lie in the eventlet package.
It fails like this on import.

[CoolCat467]

This is because eventlet does some nasty monkeypatching stuff and replaces signal handlers with its own