REF: separate out ShallowMixin (pandas-dev#29427)

Author: jbrockmendel

pandas/core/base.py

@@ -4,7 +4,7 @@
 import builtins
 from collections import OrderedDict
 import textwrap
-from typing import Dict, FrozenSet, Optional
+from typing import Dict, FrozenSet, List, Optional
 import warnings
 
 import numpy as np
@@ -569,7 +569,7 @@ def _aggregate_multiple_funcs(self, arg, _level, _axis):
                 try:
                     new_res = colg.aggregate(a)
 
-                except (TypeError, DataError):
+                except TypeError:
                     pass
                 else:
                     results.append(new_res)
@@ -618,6 +618,23 @@ def _aggregate_multiple_funcs(self, arg, _level, _axis):
                 raise ValueError("cannot combine transform and aggregation operations")
             return result
 
+    def _get_cython_func(self, arg: str) -> Optional[str]:
+        """
+        if we define an internal function for this argument, return it
+        """
+        return self._cython_table.get(arg)
+
+    def _is_builtin_func(self, arg):
+        """
+        if we define an builtin function for this argument, return it,
+        otherwise return the arg
+        """
+        return self._builtin_table.get(arg, arg)
+
+
+class ShallowMixin:
+    _attributes = []  # type: List[str]
+
     def _shallow_copy(self, obj=None, obj_type=None, **kwargs):
         """
         return a new object with the replacement attributes
@@ -633,19 +650,6 @@ def _shallow_copy(self, obj=None, obj_type=None, **kwargs):
                 kwargs[attr] = getattr(self, attr)
         return obj_type(obj, **kwargs)
 
-    def _get_cython_func(self, arg: str) -> Optional[str]:
-        """
-        if we define an internal function for this argument, return it
-        """
-        return self._cython_table.get(arg)
-
-    def _is_builtin_func(self, arg):
-        """
-        if we define an builtin function for this argument, return it,
-        otherwise return the arg
-        """
-        return self._builtin_table.get(arg, arg)
-
 
 class IndexOpsMixin:
     """

pandas/core/resample.py

@@ -17,7 +17,7 @@
 from pandas.core.dtypes.generic import ABCDataFrame, ABCSeries
 
 import pandas.core.algorithms as algos
-from pandas.core.base import DataError
+from pandas.core.base import DataError, ShallowMixin
 from pandas.core.generic import _shared_docs
 from pandas.core.groupby.base import GroupByMixin
 from pandas.core.groupby.generic import SeriesGroupBy
@@ -34,7 +34,7 @@
 _shared_docs_kwargs = dict()  # type: Dict[str, str]
 
 
-class Resampler(_GroupBy):
+class Resampler(_GroupBy, ShallowMixin):
     """
     Class for resampling datetimelike data, a groupby-like operation.
     See aggregate, transform, and apply functions on this object.

pandas/core/window/rolling.py

@@ -35,7 +35,7 @@
 )
 
 from pandas._typing import Axis, FrameOrSeries, Scalar
-from pandas.core.base import DataError, PandasObject, SelectionMixin
+from pandas.core.base import DataError, PandasObject, SelectionMixin, ShallowMixin
 import pandas.core.common as com
 from pandas.core.index import Index, ensure_index
 from pandas.core.window.common import (
@@ -50,7 +50,7 @@
 )
 
 
-class _Window(PandasObject, SelectionMixin):
+class _Window(PandasObject, ShallowMixin, SelectionMixin):
     _attributes = [
         "window",
         "min_periods",