test: polars categorical physical order deprecation and (temporarely) xfail datetime selectors (#2922)

* test: xfail polars datetime selectors

* ordered cat test coverage

* address categorical deprecation

* inline comment

* improve note, bump typing version

Author: FBruzzesi

narwhals/_utils.py

@@ -43,8 +43,6 @@
     is_numpy_array_1d_int,
     is_pandas_like_dataframe,
     is_pandas_like_series,
-    is_polars_series,
-    is_pyarrow_chunked_array,
 )
 from narwhals.exceptions import ColumnNotFoundError, DuplicateError, InvalidOperationError
 
@@ -1250,7 +1248,7 @@ def is_ordered_categorical(series: Series[Any]) -> bool:
         >>> import polars as pl
         >>> data = ["x", "y"]
         >>> s_pd = pd.Series(data, dtype=pd.CategoricalDtype(ordered=True))
-        >>> s_pl = pl.Series(data, dtype=pl.Categorical(ordering="physical"))
+        >>> s_pl = pl.Series(data, dtype=pl.Categorical(ordering="lexical"))
 
         Let's define a library-agnostic function:
 
@@ -1263,7 +1261,7 @@ def is_ordered_categorical(series: Series[Any]) -> bool:
         >>> func(s_pd)
         True
         >>> func(s_pl)
-        True
+        False
     """
     from narwhals._interchange.series import InterchangeSeries
 
@@ -1281,11 +1279,15 @@ def is_ordered_categorical(series: Series[Any]) -> bool:
         result = False
     else:
         native = series.to_native()
-        if is_polars_series(native):
+        impl = series.implementation
+        if impl.is_polars() and impl._backend_version() < (1, 32):
+            # NOTE: Deprecated https://github.com/pola-rs/polars/pull/23779
+            # Since version 1.32.0, ordering parameter is ignored and
+            # it always behaves as if 'lexical' was passed.
             result = cast("pl.Categorical", native.dtype).ordering == "physical"
-        elif is_pandas_like_series(native):
+        elif impl.is_pandas_like():
             result = bool(native.cat.ordered)
-        elif is_pyarrow_chunked_array(native):
+        elif impl.is_pyarrow():
             from narwhals._arrow.utils import is_dictionary
 
             result = is_dictionary(native.type) and native.type.ordered

pyproject.toml

@@ -72,7 +72,7 @@ typing = [  # keep some of these pinned and bump periodically so there's fewer s
   "pyright",
   "pyarrow-stubs==19.2",
   "sqlframe",
-  "polars==1.30.0",
+  "polars==1.32.0",
   "uv",
   "narwhals[ibis]",
 ]

tests/selectors_test.py

@@ -89,7 +89,8 @@ def test_datetime(constructor: Constructor, request: pytest.FixtureRequest) -> N
         or ("pandas" in str(constructor) and PANDAS_VERSION < (2,))
         or "ibis" in str(constructor)
         # https://github.com/pola-rs/polars/issues/23767
-        or ("polars" in str(constructor) and POLARS_VERSION == (1, 32, 0, 1))
+        # TODO(FBruzzesi): Manage polars version
+        or ("polars" in str(constructor) and POLARS_VERSION >= (1, 32, 0))
     ):
         request.applymarker(pytest.mark.xfail)
     if "modin" in str(constructor):

tests/series_only/is_ordered_categorical_test.py

@@ -5,7 +5,7 @@
 import pytest
 
 import narwhals as nw
-from narwhals._utils import Version
+from narwhals._utils import Implementation, Version
 from tests.utils import POLARS_VERSION
 
 if TYPE_CHECKING:
@@ -15,6 +15,7 @@
 
 class MockCompliantSeries:
     _version = Version.MAIN
+    _implementation = Implementation.UNKNOWN
 
     def __narwhals_series__(self) -> Any:
         return self
@@ -34,9 +35,9 @@ def test_is_ordered_categorical_polars() -> None:
 
     s: IntoSeries | Any
     s = pl.Series(["a", "b"], dtype=pl.Categorical)
-    if POLARS_VERSION < (1, 32):
+    if POLARS_VERSION < (1, 32):  # pragma: no cover
         assert nw.is_ordered_categorical(nw.from_native(s, series_only=True))
-    else:  # pragma: no cover
+    else:
         # Post 1.32 there's no physical ordering for categoricals anymore.
         assert not nw.is_ordered_categorical(nw.from_native(s, series_only=True))
     s = pl.Series(["a", "b"], dtype=pl.Categorical(ordering="lexical"))