DatetimeIndex get_loc validates date object

pandas/core/arrays/datetimes.py

@@ -1,4 +1,4 @@
-from datetime import datetime, time, timedelta, tzinfo
+from datetime import date, datetime, time, timedelta, tzinfo
 from typing import Optional, Union
 import warnings
 
@@ -152,7 +152,7 @@ class DatetimeArray(dtl.TimelikeOps, dtl.DatelikeOps):
 
     _typ = "datetimearray"
     _scalar_type = Timestamp
-    _recognized_scalars = (datetime, np.datetime64)
+    _recognized_scalars = (datetime, np.datetime64, date)
     _is_recognized_dtype = is_datetime64_any_dtype
 
     # define my properties & methods for delegation

pandas/core/internals/blocks.py

@@ -1,4 +1,4 @@
-from datetime import datetime, timedelta
+from datetime import date, datetime, timedelta
 import inspect
 import re
 from typing import TYPE_CHECKING, Any, List, Optional, Type, Union, cast
@@ -2226,6 +2226,8 @@ def _can_hold_element(self, element: Any) -> bool:
             return is_datetime64_dtype(tipo)
         elif element is NaT:
             return True
+        elif isinstance(element, date):
+            return True
         elif isinstance(element, datetime):
             if self.is_datetimetz:
                 return tz_compare(element.tzinfo, self.dtype.tz)

pandas/tests/arithmetic/test_datetime64.py

@@ -70,10 +70,6 @@ def test_compare_zerodim(self, tz_naive_fixture, box_with_array):
             4.0,
             object(),
             timedelta(days=2),
-            # GH#19800, GH#19301 datetime.date comparison raises to
-            #  match DatetimeIndex/Timestamp.  This also matches the behavior
-            #  of stdlib datetime.datetime
-            datetime(2001, 1, 1).date(),
             # GH#19301 None and NaN are *not* cast to NaT for comparisons
             None,
             np.nan,

pandas/tests/indexes/datetimes/test_datetime.py

@@ -403,3 +403,10 @@ def test_split_non_utc(self):
         result = np.split(indices, indices_or_sections=[])[0]
         expected = indices._with_freq(None)
         tm.assert_index_equal(result, expected)
+
+    def test_in_contains_date_object(self):
+        # GH#35466
+        d1 = date(2002, 9, 1)
+        idx1 = DatetimeIndex([d1])
+        assert d1 in idx1
+        assert "2002-09-01" in idx1

pandas/tests/internals/test_internals.py

@@ -1067,7 +1067,7 @@ def test_datetime_block_can_hold_element(self):
             arr[0] = val
 
         val = date(2010, 10, 10)
-        assert not block._can_hold_element(val)
+        assert block._can_hold_element(val)
 
         msg = (
             "value should be a 'Timestamp', 'NaT', "