BUG: datetime.date objects don't get parsed for non-ISO formats (pandas-dev#50109)

* parse datetime.date in non-ISO path

* reword

Co-authored-by: MarcoGorelli <>

Author: MarcoGorelli

doc/source/whatsnew/v2.0.0.rst

@@ -703,7 +703,7 @@ Datetimelike
 - Bug in subtracting a ``datetime`` scalar from :class:`DatetimeIndex` failing to retain the original ``freq`` attribute (:issue:`48818`)
 - Bug in ``pandas.tseries.holiday.Holiday`` where a half-open date interval causes inconsistent return types from :meth:`USFederalHolidayCalendar.holidays` (:issue:`49075`)
 - Bug in rendering :class:`DatetimeIndex` and :class:`Series` and :class:`DataFrame` with timezone-aware dtypes with ``dateutil`` or ``zoneinfo`` timezones near daylight-savings transitions (:issue:`49684`)
-- Bug in :func:`to_datetime` was raising ``ValueError`` when parsing :class:`Timestamp`, ``datetime``, or ``np.datetime64`` objects with non-ISO8601 ``format`` (:issue:`49298`, :issue:`50036`)
+- Bug in :func:`to_datetime` was raising ``ValueError`` when parsing :class:`Timestamp`, ``datetime.datetime``, ``datetime.date``, or ``np.datetime64`` objects when non-ISO8601 ``format`` was passed (:issue:`49298`, :issue:`50036`)
 -
 
 Timedelta

pandas/_libs/tslibs/strptime.pyx

@@ -1,6 +1,7 @@
 """Strptime-related classes and functions.
 """
 from cpython.datetime cimport (
+    PyDate_Check,
     PyDateTime_Check,
     date,
     import_datetime,
@@ -34,6 +35,7 @@ from pandas._libs.tslibs.np_datetime cimport (
     check_dts_bounds,
     npy_datetimestruct,
     npy_datetimestruct_to_datetime,
+    pydate_to_dt64,
     pydatetime_to_dt64,
 )
 from pandas._libs.tslibs.timestamps cimport _Timestamp
@@ -173,6 +175,10 @@ def array_strptime(
                 check_dts_bounds(&dts)
             result_timezone[i] = val.tzinfo
             continue
+        elif PyDate_Check(val):
+            iresult[i] = pydate_to_dt64(val, &dts)
+            check_dts_bounds(&dts)
+            continue
         elif is_datetime64_object(val):
             iresult[i] = get_datetime64_nanos(val, NPY_FR_ns)
             continue

pandas/tests/tools/test_to_datetime.py

@@ -3,6 +3,7 @@
 import calendar
 from collections import deque
 from datetime import (
+    date,
     datetime,
     timedelta,
     timezone,
@@ -469,6 +470,16 @@ def test_to_datetime_mixed_datetime_and_string(self):
         expected = to_datetime([d1, d2]).tz_convert(pytz.FixedOffset(-60))
         tm.assert_index_equal(res, expected)
 
+    @pytest.mark.parametrize(
+        "format", ["%Y-%m-%d", "%Y-%d-%m"], ids=["ISO8601", "non-ISO8601"]
+    )
+    def test_to_datetime_mixed_date_and_string(self, format):
+        # https://github.com/pandas-dev/pandas/issues/50108
+        d1 = date(2020, 1, 2)
+        res = to_datetime(["2020-01-01", d1], format=format)
+        expected = DatetimeIndex(["2020-01-01", "2020-01-02"])
+        tm.assert_index_equal(res, expected)
+
     @pytest.mark.parametrize(
         "fmt",
         ["%Y-%d-%m %H:%M:%S%z", "%Y-%m-%d %H:%M:%S%z"],