https://github.com/pandas-dev/pandas-stubs/pull/1531#discussion_r2595486542

Author: cmp0xff

pandas-stubs/core/indexes/accessors.pyi

@@ -446,7 +446,7 @@ class DtDescriptor:
     @overload
     def __get__(
         self, instance: Series[Never], owner: type[Series]
-    ) -> TimestampProperties | TimedeltaProperties | PeriodProperties: ...
+    ) -> CombinedDatetimelikeProperties: ...
     @overload
     def __get__(
         self, instance: Series[Timestamp], owner: type[Series]

tests/series/test_properties.py

@@ -8,6 +8,7 @@
 from pandas.core.arrays.timedeltas import TimedeltaArray
 from pandas.core.frame import DataFrame
 from pandas.core.indexes.accessors import (
+    CombinedDatetimelikeProperties,
     DatetimeProperties,
     PeriodProperties,
     TimedeltaProperties,
@@ -52,17 +53,30 @@ def test_property_dt() -> None:
     # python/mypy#19952: mypy gives Any
     check(
         assert_type(  # type: ignore[assert-type]
-            df["ts"].dt, "TimestampProperties | TimedeltaProperties | PeriodProperties"
+            df["ts"].dt, CombinedDatetimelikeProperties
         ),
         DatetimeProperties,
     )
     check(
         assert_type(  # type: ignore[assert-type]
-            df["td"].dt, "TimestampProperties | TimedeltaProperties | PeriodProperties"
+            df["td"].dt, CombinedDatetimelikeProperties
         ),
         TimedeltaProperties,
     )
 
+    check(
+        assert_type(df["ts"].dt.year, "Series[int]"),  # type: ignore[assert-type]
+        Series,
+        np.integer,
+    )
+    check(
+        assert_type(  # type: ignore[assert-type]
+            df["td"].dt.total_seconds(), "Series[float]"
+        ),
+        Series,
+        np.floating,
+    )
+
     if TYPE_CHECKING_INVALID_USAGE:
         _0 = Series([1]).dt  # type: ignore[arg-type] # pyright: ignore[reportAttributeAccessIssue]
         _1 = Series(["2025-01-01"]).dt  # type: ignore[arg-type] # pyright: ignore[reportAttributeAccessIssue]