From 2f503a8dc3fa04d24d7add7b08916ff00760b9eb Mon Sep 17 00:00:00 2001
From: David Anderson <cantspamdave@gmail.com>
Date: Sun, 24 Jan 2021 18:45:13 +0000
Subject: [PATCH 1/2] BUG: GH35830 Restore index by Date to DatetimeIndex

DatetimeIndex has supported indexing by date for many many years. This was broken
after 1.0.5. This attempts to restore support by promoting date a non--tz aware
datetime at midnight.
---
 pandas/core/arrays/datetimelike.py |  7 ++++++-
 pandas/core/indexes/datetimes.py   |  4 ++++
 pandas/tests/indexing/test_loc.py  | 12 +++++++++++-
 3 files changed, 21 insertions(+), 2 deletions(-)

diff --git a/pandas/core/arrays/datetimelike.py b/pandas/core/arrays/datetimelike.py
index be9864731842d..2598cb722a046 100644
--- a/pandas/core/arrays/datetimelike.py
+++ b/pandas/core/arrays/datetimelike.py
@@ -1,6 +1,6 @@
 from __future__ import annotations
 
-from datetime import datetime, timedelta
+from datetime import date, datetime, time, timedelta
 import operator
 from typing import (
     TYPE_CHECKING,
@@ -543,6 +543,11 @@ def _validate_scalar(
         -------
         self._scalar_type or NaT
         """
+
+        if type(value) == date:
+            # GH35830
+            value = datetime.combine(value, time.min)
+
         if isinstance(value, str):
             # NB: Careful about tzawareness
             try:
diff --git a/pandas/core/indexes/datetimes.py b/pandas/core/indexes/datetimes.py
index 8329c41a74596..1de3653a395b1 100644
--- a/pandas/core/indexes/datetimes.py
+++ b/pandas/core/indexes/datetimes.py
@@ -649,6 +649,10 @@ def get_loc(self, key, method=None, tolerance=None):
         if is_valid_nat_for_dtype(key, self.dtype):
             key = NaT
 
+        if type(key) == date:
+            # GH35830
+            key = datetime.combine(key, time.min)
+
         if isinstance(key, self._data._recognized_scalars):
             # needed to localize naive datetimes
             self._deprecate_mismatched_indexing(key)
diff --git a/pandas/tests/indexing/test_loc.py b/pandas/tests/indexing/test_loc.py
index 68f12a939e061..18cb4104a1c2a 100644
--- a/pandas/tests/indexing/test_loc.py
+++ b/pandas/tests/indexing/test_loc.py
@@ -1,5 +1,5 @@
 """ test label based indexing with loc """
-from datetime import datetime, time, timedelta
+from datetime import date, datetime, time, timedelta
 from io import StringIO
 import re
 
@@ -2090,3 +2090,13 @@ def test_loc_iloc_setitem_with_listlike(self, size, array_fn):
         ser = Series(0, index=list("abcde"), dtype=object)
         ser.iloc[0] = arr
         tm.assert_series_equal(ser, expected)
+
+    def test_loc_getitem_date_objs_with_datetimeindex(self):
+        # GH35830
+        dates = [date(2000, 1, i) for i in (1, 2, 5)]
+        values = [1, 2, 3]
+        s = Series(values, pd.DatetimeIndex(dates))
+        i = 1
+        expected = values[i]
+        result = s.loc[dates[i]]
+        assert result == expected

From 670e868d6ea5f17dd6e1ca1a77dabdebe52bccf7 Mon Sep 17 00:00:00 2001
From: David Anderson <cantspamdave@gmail.com>
Date: Sun, 24 Jan 2021 20:49:05 +0000
Subject: [PATCH 2/2] fixing inconsistent-namespace-usage

---
 pandas/tests/indexing/test_loc.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/pandas/tests/indexing/test_loc.py b/pandas/tests/indexing/test_loc.py
index 18cb4104a1c2a..55355f615b2fe 100644
--- a/pandas/tests/indexing/test_loc.py
+++ b/pandas/tests/indexing/test_loc.py
@@ -2095,7 +2095,7 @@ def test_loc_getitem_date_objs_with_datetimeindex(self):
         # GH35830
         dates = [date(2000, 1, i) for i in (1, 2, 5)]
         values = [1, 2, 3]
-        s = Series(values, pd.DatetimeIndex(dates))
+        s = Series(values, dates)
         i = 1
         expected = values[i]
         result = s.loc[dates[i]]