DatetimeIndex get_loc validates date object

Author: knabben

pandas/core/indexes/datetimes.py

@@ -589,8 +589,11 @@ def get_loc(self, key, method=None, tolerance=None):
         if is_valid_nat_for_dtype(key, self.dtype):
             key = NaT
 
-        if isinstance(key, self._data._recognized_scalars):
-            # needed to localize naive datetimes
+        if any([
+            isinstance(key, self._data._recognized_scalars) or
+            isinstance(key, date)
+        ]):
+            # needed to localize naive dates and datetimes
             key = self._maybe_cast_for_get_loc(key)
 
         elif isinstance(key, str):

pandas/tests/indexes/datetimes/test_datetime.py

@@ -402,3 +402,10 @@ 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