BUG: DatetimeIndex.shift with non-nano

doc/source/whatsnew/v2.2.0.rst

@@ -447,6 +447,7 @@ Datetimelike
 - Bug in :func:`testing.assert_extension_array_equal` that could use the wrong unit when comparing resolutions (:issue:`55730`)
 - Bug in :func:`to_datetime` and :class:`DatetimeIndex` when passing a list of mixed-string-and-numeric types incorrectly raising (:issue:`55780`)
 - Bug in :func:`to_datetime` and :class:`DatetimeIndex` when passing mixed-type objects with a mix of timezones or mix of timezone-awareness failing to raise ``ValueError`` (:issue:`55693`)
+- Bug in :meth:`DatetimeIndex.shift` with non-nanosecond resolution incorrectly returning with nanosecond resolution (:issue:`56117`)
 - Bug in :meth:`DatetimeIndex.union` returning object dtype for tz-aware indexes with the same timezone but different units (:issue:`55238`)
 - Bug in :meth:`Index.is_monotonic_increasing` and :meth:`Index.is_monotonic_decreasing` always caching :meth:`Index.is_unique` as ``True`` when first value in index is ``NaT`` (:issue:`55755`)
 - Bug in :meth:`Index.view` to a datetime64 dtype with non-supported resolution incorrectly raising (:issue:`55710`)
@@ -461,7 +462,6 @@ Datetimelike
 - Bug in creating a :class:`Index`, :class:`Series`, or :class:`DataFrame` with a non-nanosecond ``datetime64`` dtype and inputs that would be out of bounds for a ``datetime64[ns]`` incorrectly raising ``OutOfBoundsDatetime`` (:issue:`55756`)
 - Bug in parsing datetime strings with nanosecond resolution with non-ISO8601 formats incorrectly truncating sub-microsecond components (:issue:`56051`)
 - Bug in parsing datetime strings with sub-second resolution and trailing zeros incorrectly inferring second or millisecond resolution (:issue:`55737`)
-- Bug in :meth:`DatetimeIndex.shift` with non-nanosecond resolution incorrectly returning with nanosecond resolution (:issue:`??`)
 -
 
 Timedelta