Call finalize in Series.dt (pandas-dev#36554)

xref pandas-dev#28283

Author: TomAugspurger

doc/source/whatsnew/v1.2.0.rst

@@ -374,6 +374,7 @@ Other
 ^^^^^
 - Bug in :meth:`DataFrame.replace` and :meth:`Series.replace` incorrectly raising ``AssertionError`` instead of ``ValueError`` when invalid parameter combinations are passed (:issue:`36045`)
 - Bug in :meth:`DataFrame.replace` and :meth:`Series.replace` with numeric values and string ``to_replace`` (:issue:`34789`)
+- Fixed metadata propagation in the :class:`Series.dt` accessor (:issue:`28283`)
 - Bug in :meth:`Series.transform` would give incorrect results or raise when the argument ``func`` was dictionary (:issue:`35811`)
 - Bug in :meth:`Index.union` behaving differently depending on whether operand is a :class:`Index` or other list-like (:issue:`36384`)
 

pandas/core/indexes/accessors.py

@@ -78,7 +78,7 @@ def _delegate_property_get(self, name):
         else:
             index = self._parent.index
         # return the result as a Series, which is by definition a copy
-        result = Series(result, index=index, name=self.name)
+        result = Series(result, index=index, name=self.name).__finalize__(self._parent)
 
         # setting this object will show a SettingWithCopyWarning/Error
         result._is_copy = (
@@ -106,7 +106,9 @@ def _delegate_method(self, name, *args, **kwargs):
         if not is_list_like(result):
             return result
 
-        result = Series(result, index=self._parent.index, name=self.name)
+        result = Series(result, index=self._parent.index, name=self.name).__finalize__(
+            self._parent
+        )
 
         # setting this object will show a SettingWithCopyWarning/Error
         result._is_copy = (
@@ -371,7 +373,11 @@ def components(self):
         3     0      0        0        3             0             0            0
         4     0      0        0        4             0             0            0
         """
-        return self._get_values().components.set_index(self._parent.index)
+        return (
+            self._get_values()
+            .components.set_index(self._parent.index)
+            .__finalize__(self._parent)
+        )
 
     @property
     def freq(self):

pandas/tests/generic/test_finalize.py

@@ -678,7 +678,6 @@ def test_string_method(method):
     ],
     ids=idfn,
 )
-@not_implemented_mark
 def test_datetime_method(method):
     s = pd.Series(pd.date_range("2000", periods=4))
     s.attrs = {"a": 1}
@@ -714,7 +713,6 @@ def test_datetime_method(method):
         "days_in_month",
     ],
 )
-@not_implemented_mark
 def test_datetime_property(attr):
     s = pd.Series(pd.date_range("2000", periods=4))
     s.attrs = {"a": 1}
@@ -725,7 +723,6 @@ def test_datetime_property(attr):
 @pytest.mark.parametrize(
     "attr", ["days", "seconds", "microseconds", "nanoseconds", "components"]
 )
-@not_implemented_mark
 def test_timedelta_property(attr):
     s = pd.Series(pd.timedelta_range("2000", periods=4))
     s.attrs = {"a": 1}
@@ -734,7 +731,6 @@ def test_timedelta_property(attr):
 
 
 @pytest.mark.parametrize("method", [operator.methodcaller("total_seconds")])
-@not_implemented_mark
 def test_timedelta_methods(method):
     s = pd.Series(pd.timedelta_range("2000", periods=4))
     s.attrs = {"a": 1}