TYP: avoid inherit_names for DatetimeIndexOpsMixin (#49804)

Author: twoertwein

pandas/core/indexes/datetimelike.py

@@ -3,6 +3,10 @@
 """
 from __future__ import annotations
 
+from abc import (
+    ABC,
+    abstractmethod,
+)
 from datetime import datetime
 from typing import (
     TYPE_CHECKING,
@@ -61,10 +65,7 @@
     Index,
     _index_shared_docs,
 )
-from pandas.core.indexes.extension import (
-    NDArrayBackedExtensionIndex,
-    inherit_names,
-)
+from pandas.core.indexes.extension import NDArrayBackedExtensionIndex
 from pandas.core.indexes.range import RangeIndex
 from pandas.core.tools.timedeltas import to_timedelta
 
@@ -77,21 +78,17 @@
 _TDT = TypeVar("_TDT", bound="DatetimeTimedeltaMixin")
 
 
-@inherit_names(
-    ["inferred_freq", "_resolution_obj", "resolution"],
-    DatetimeLikeArrayMixin,
-    cache=True,
-)
-@inherit_names(["mean", "freqstr"], DatetimeLikeArrayMixin)
-class DatetimeIndexOpsMixin(NDArrayBackedExtensionIndex):
+class DatetimeIndexOpsMixin(NDArrayBackedExtensionIndex, ABC):
     """
     Common ops mixin to support a unified interface datetimelike Index.
     """
 
     _can_hold_strings = False
     _data: DatetimeArray | TimedeltaArray | PeriodArray
-    freqstr: str | None
-    _resolution_obj: Resolution
+
+    @doc(DatetimeLikeArrayMixin.mean)
+    def mean(self, *, skipna: bool = True, axis: int | None = 0):
+        return self._data.mean(skipna=skipna, axis=axis)
 
     @property
     def freq(self) -> BaseOffset | None:
@@ -106,6 +103,21 @@ def freq(self, value) -> None:
     def asi8(self) -> npt.NDArray[np.int64]:
         return self._data.asi8
 
+    @property
+    @doc(DatetimeLikeArrayMixin.freqstr)
+    def freqstr(self) -> str | None:
+        return self._data.freqstr
+
+    @cache_readonly
+    @abstractmethod
+    def _resolution_obj(self) -> Resolution:
+        ...
+
+    @cache_readonly
+    @doc(DatetimeLikeArrayMixin.resolution)
+    def resolution(self) -> str:
+        return self._data.resolution
+
     # ------------------------------------------------------------------------
 
     @cache_readonly
@@ -390,7 +402,7 @@ def _maybe_cast_listlike_indexer(self, keyarr):
         return Index(res, dtype=res.dtype)
 
 
-class DatetimeTimedeltaMixin(DatetimeIndexOpsMixin):
+class DatetimeTimedeltaMixin(DatetimeIndexOpsMixin, ABC):
     """
     Mixin class for methods shared by DatetimeIndex and TimedeltaIndex,
     but not PeriodIndex
@@ -461,6 +473,11 @@ def shift(self: _TDT, periods: int = 1, freq=None) -> _TDT:
         )
         return type(self)._simple_new(result, name=self.name)
 
+    @cache_readonly
+    @doc(DatetimeLikeArrayMixin.inferred_freq)
+    def inferred_freq(self) -> str | None:
+        return self._data.inferred_freq
+
     # --------------------------------------------------------------------
     # Set Operation Methods
 

pandas/core/indexes/datetimes.py

@@ -109,7 +109,7 @@ def _new_DatetimeIndex(cls, d):
     DatetimeArray,
     wrap=True,
 )
-@inherit_names(["is_normalized", "_resolution_obj"], DatetimeArray, cache=True)
+@inherit_names(["is_normalized"], DatetimeArray, cache=True)
 @inherit_names(
     [
         "tz",
@@ -248,7 +248,6 @@ def _engine_type(self) -> type[libindex.DatetimeEngine]:
         return libindex.DatetimeEngine
 
     _data: DatetimeArray
-    inferred_freq: str | None
     tz: dt.tzinfo | None
 
     # --------------------------------------------------------------------
@@ -291,6 +290,10 @@ def isocalendar(self) -> DataFrame:
         df = self._data.isocalendar()
         return df.set_index(self)
 
+    @cache_readonly
+    def _resolution_obj(self) -> Resolution:
+        return self._data._resolution_obj
+
     # --------------------------------------------------------------------
     # Constructors
 

pandas/core/indexes/period.py

@@ -156,8 +156,7 @@ def _engine_type(self) -> type[libindex.PeriodEngine]:
         return libindex.PeriodEngine
 
     @cache_readonly
-    # Signature of "_resolution_obj" incompatible with supertype "DatetimeIndexOpsMixin"
-    def _resolution_obj(self) -> Resolution:  # type: ignore[override]
+    def _resolution_obj(self) -> Resolution:
         # for compat with DatetimeIndex
         return self.dtype._resolution_obj
 

pandas/core/indexes/timedeltas.py

@@ -6,6 +6,7 @@
     lib,
 )
 from pandas._libs.tslibs import (
+    Resolution,
     Timedelta,
     to_offset,
 )
@@ -112,6 +113,12 @@ def _engine_type(self) -> type[libindex.TimedeltaEngine]:
     # Use base class method instead of DatetimeTimedeltaMixin._get_string_slice
     _get_string_slice = Index._get_string_slice
 
+    # error: Signature of "_resolution_obj" incompatible with supertype
+    # "DatetimeIndexOpsMixin"
+    @property
+    def _resolution_obj(self) -> Resolution | None:  # type: ignore[override]
+        return self._data._resolution_obj
+
     # -------------------------------------------------------------------
     # Constructors