[Bug]: is_ibis_table unsafe for python==3.8 #905
Description
Describe the bug
Original comment
@MarcoGorelli do you have any ideas on what is causing this error for ibis on python==3.8?
https://github.com/vega/altair/actions/runs/10681007191/job/29608118357?pr=3547
I did a merge update from the GitHub UI, but haven't been able to track down the cause yet.
Update
Seems to be this commit which causes the issue (only for 3.8) 3d246b7
Hot fix
Maybe None might be the wrong choice here, but works in altair to pass tests
def is_ibis_table(df: Any) -> TypeGuard[ibis.Table]:
"""Check whether `df` is a Ibis Table without importing Ibis."""
return bool((ibis := get_ibis()) is not None and (ibis_table := getattr(ibis, "Table", None)) and isinstance(df, ibis_table))Steps or code to reproduce the bug
Expected results
No error is thrown
Actual results
..\..\..\AppData\Local\hatch\env\virtual\altair\CXM7NV9I\hatch-test.py3.8\lib\site-packages\narwhals\dependencies.py:128: in is_ibis_table
return bool((ibis := get_ibis()) is not None and isinstance(df, ibis.Table))
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
name = 'Table'
def __getattr__(name: str) -> BaseBackend:
"""Load backends in a lazy way with `ibis.<backend-name>`.
This also registers the backend options.
Examples
--------
>>> import ibis
>>> con = ibis.sqlite.connect(...)
When accessing the `sqlite` attribute of the `ibis` module, this function
is called, and a backend with the `sqlite` name is tried to load from
the `ibis.backends` entrypoints. If successful, the `ibis.sqlite`
attribute is "cached", so this function is only called the first time.
"""
entry_points = {ep for ep in util.backend_entry_points() if ep.name == name}
if not entry_points:
msg = f"module 'ibis' has no attribute '{name}'. "
if name in _KNOWN_BACKENDS:
msg += f"""If you are trying to access the '{name}' backend,
try installing it first with `pip install ibis-{name}`"""
> raise AttributeError(msg)
E AttributeError: module 'ibis' has no attribute 'Table'.
..\..\..\AppData\Local\hatch\env\virtual\altair\CXM7NV9I\hatch-test.py3.8\lib\site-packages\ibis\__init__.py:58: AttributeErrorPlease run narwhals.show_version() and enter the output below.
https://github.com/narwhals-dev/narwhals/commit/3d246b7dc642cc362626a757abd032fd6f2c2b06Relevant log output
No response