Refactor DataFrame and Series methods to enhance attribute finalization logic

Author: fbourgey

pandas/core/frame.py

@@ -8207,10 +8207,6 @@ def to_series(right):
                 level=level,
             )
             right = left._maybe_align_series_as_frame(right, axis)
-
-            # Ensure attributes are consistent between the aligned and original objects
-            if right.attrs != getattr(other, "attrs", {}):
-                right.attrs = getattr(other, "attrs", {}).copy()
         return left, right
 
     def _maybe_align_series_as_frame(self, series: Series, axis: AxisInt):
@@ -8239,7 +8235,7 @@ def _maybe_align_series_as_frame(self, series: Series, axis: AxisInt):
             index=self.index,
             columns=self.columns,
             dtype=rvalues.dtype,
-        )
+        ).__finalize__(series)
 
     def _flex_arith_method(
         self, other, op, *, axis: Axis = "columns", level=None, fill_value=None
@@ -8285,13 +8281,13 @@ def _construct_result(self, result, other=None) -> DataFrame:
         -------
         DataFrame
         """
-        if not getattr(self, "attrs", None) and getattr(other, "attrs", None):
-            self.__finalize__(other)
         out = self._constructor(result, copy=False).__finalize__(self)
         # Pin columns instead of passing to constructor for compat with
         #  non-unique columns case
         out.columns = self.columns
         out.index = self.index
+        if not getattr(self, "attrs", None) and getattr(other, "attrs", None):
+            out = out.__finalize__(other)
         return out
 
     def __divmod__(self, other) -> tuple[DataFrame, DataFrame]:

pandas/core/series.py

@@ -5970,12 +5970,12 @@ def _construct_result(
         dtype = getattr(result, "dtype", None)
         out = self._constructor(result, index=self.index, dtype=dtype, copy=False)
         out = out.__finalize__(self)
+        if getattr(other, "attrs", None):
+            out.__finalize__(other)
 
         # Set the result's name after __finalize__ is called because __finalize__
         #  would set it back to self.name
         out.name = name
-        if not getattr(self, "attrs", None) and getattr(other, "attrs", None):
-            out.__finalize__(other)
         return out
 
     def _flex_method(self, other, op, *, level=None, fill_value=None, axis: Axis = 0):