BUG: Fix pyarrow groupby tests (#48443)

Author: jbrockmendel

pandas/core/series.py

@@ -573,7 +573,10 @@ def _set_axis(self, axis: int, labels: AnyArrayLike | list) -> None:
         """
         labels = ensure_index(labels)
 
-        if labels._is_all_dates:
+        if labels._is_all_dates and not (
+            type(labels) is Index and not isinstance(labels.dtype, np.dtype)
+        ):
+            # exclude e.g. timestamp[ns][pyarrow] dtype from this casting
             deep_labels = labels
             if isinstance(labels, CategoricalIndex):
                 deep_labels = labels.categories

pandas/tests/extension/test_arrow.py

@@ -516,15 +516,6 @@ def test_groupby_extension_no_sort(self, data_for_grouping, request):
                     reason=f"pyarrow doesn't support factorizing {pa_dtype}",
                 )
             )
-        elif pa.types.is_date(pa_dtype) or (
-            pa.types.is_timestamp(pa_dtype) and pa_dtype.tz is None
-        ):
-            request.node.add_marker(
-                pytest.mark.xfail(
-                    raises=AttributeError,
-                    reason="GH 34986",
-                )
-            )
         super().test_groupby_extension_no_sort(data_for_grouping)
 
     def test_groupby_extension_transform(self, data_for_grouping, request):
@@ -551,8 +542,7 @@ def test_groupby_extension_apply(
         self, data_for_grouping, groupby_apply_op, request
     ):
         pa_dtype = data_for_grouping.dtype.pyarrow_dtype
-        # Is there a better way to get the "series" ID for groupby_apply_op?
-        is_series = "series" in request.node.nodeid
+        # TODO: Is there a better way to get the "object" ID for groupby_apply_op?
         is_object = "object" in request.node.nodeid
         if pa.types.is_duration(pa_dtype):
             request.node.add_marker(
@@ -571,13 +561,6 @@ def test_groupby_extension_apply(
                         reason="GH 47514: _concat_datetime expects axis arg.",
                     )
                 )
-            elif not is_series:
-                request.node.add_marker(
-                    pytest.mark.xfail(
-                        raises=AttributeError,
-                        reason="GH 34986",
-                    )
-                )
         with tm.maybe_produces_warning(
             PerformanceWarning, pa_version_under7p0, check_stacklevel=False
         ):
@@ -610,16 +593,6 @@ def test_groupby_extension_agg(self, as_index, data_for_grouping, request):
                     reason=f"pyarrow doesn't support factorizing {pa_dtype}",
                 )
             )
-        elif as_index is True and (
-            pa.types.is_date(pa_dtype)
-            or (pa.types.is_timestamp(pa_dtype) and pa_dtype.tz is None)
-        ):
-            request.node.add_marker(
-                pytest.mark.xfail(
-                    raises=AttributeError,
-                    reason="GH 34986",
-                )
-            )
         with tm.maybe_produces_warning(
             PerformanceWarning, pa_version_under7p0, check_stacklevel=False
         ):
@@ -1464,12 +1437,13 @@ def test_diff(self, data, periods, request):
     @pytest.mark.parametrize("dropna", [True, False])
     def test_value_counts(self, all_data, dropna, request):
         pa_dtype = all_data.dtype.pyarrow_dtype
-        if pa.types.is_date(pa_dtype) or (
-            pa.types.is_timestamp(pa_dtype) and pa_dtype.tz is None
-        ):
+        if (
+            pa.types.is_date(pa_dtype)
+            or (pa.types.is_timestamp(pa_dtype) and pa_dtype.tz is None)
+        ) and dropna:
             request.node.add_marker(
                 pytest.mark.xfail(
-                    raises=AttributeError,
+                    raises=NotImplementedError,  # tries casting to i8
                     reason="GH 34986",
                 )
             )
@@ -1489,7 +1463,7 @@ def test_value_counts_with_normalize(self, data, request):
         ):
             request.node.add_marker(
                 pytest.mark.xfail(
-                    raises=AttributeError,
+                    raises=NotImplementedError,  # tries casting to i8
                     reason="GH 34986",
                 )
             )