Backport PR #27556: BUG: Allow ensure_index to coerce nan to NaT with numpy object array and tz Timestamp (#27561)

Author: meeseeksmachine

doc/source/whatsnew/v0.25.1.rst

@@ -50,7 +50,7 @@ Timedelta
 Timezones
 ^^^^^^^^^
 
--
+- Bug in :class:`Index` where a numpy object array with a timezone aware :class:`Timestamp` and ``np.nan`` would not return a :class:`DatetimeIndex` (:issue:`27011`)
 -
 -
 

pandas/core/indexes/base.py

@@ -489,19 +489,15 @@ def __new__(
  pass
  elif inferred != "string":
  if inferred.startswith("datetime"):
- if (
- lib.is_datetime_with_singletz_array(subarr)
- or "tz" in kwargs
- ):
- # only when subarr has the same tz
- from pandas import DatetimeIndex
+ from pandas import DatetimeIndex
 
- try:
- return DatetimeIndex(
- subarr, copy=copy, name=name, **kwargs
- )
- except OutOfBoundsDatetime:
- pass
+ try:
+ return DatetimeIndex(subarr, copy=copy, name=name, **kwargs)
+ except (ValueError, OutOfBoundsDatetime):
+ # GH 27011
+ # If we have mixed timezones, just send it
+ # down the base constructor
+ pass
 
  elif inferred.startswith("timedelta"):
  from pandas import TimedeltaIndex

pandas/tests/arrays/interval/test_interval.py

@@ -42,10 +42,9 @@ class TestAttributes:
  (0, 1),
  (Timedelta("0 days"), Timedelta("1 day")),
  (Timestamp("2018-01-01"), Timestamp("2018-01-02")),
- pytest.param(
+ (
  Timestamp("2018-01-01", tz="US/Eastern"),
  Timestamp("2018-01-02", tz="US/Eastern"),
- marks=pytest.mark.xfail(strict=True, reason="GH 27011"),
  ),
  ],
  )

pandas/tests/indexes/datetimes/test_construction.py

@@ -822,6 +822,12 @@ def test_constructor_wrong_precision_raises(self):
  with pytest.raises(ValueError):
  pd.DatetimeIndex(["2000"], dtype="datetime64[us]")
 
+ def test_index_constructor_with_numpy_object_array_and_timestamp_tz_with_nan(self):
+ # GH 27011
+ result = Index(np.array([Timestamp("2019", tz="UTC"), np.nan], dtype=object))
+ expected = DatetimeIndex([Timestamp("2019", tz="UTC"), pd.NaT])
+ tm.assert_index_equal(result, expected)
+
 
 class TestTimeSeries:
  def test_dti_constructor_preserve_dti_freq(self):