BUG: numpy.split on non-UTC changes original time (#14042)

doc/source/whatsnew/v0.22.0.txt

@@ -96,7 +96,7 @@ Conversion
 Indexing
 ^^^^^^^^
 
--
+- Bug in ``numpy`` ``array_wrap`` with a pandas ``Series``/``Index`` (:issue:`14042`)
 -
 -
 

pandas/core/indexes/base.py

@@ -573,7 +573,13 @@ def __array_wrap__(self, result, context=None):
 
  attrs = self._get_attributes_dict()
  attrs = self._maybe_update_attributes(attrs)
- return Index(result, **attrs)
+ from pandas.core.dtypes.generic import ABCDatetimeIndex
+ if issubclass(self, ABCDatetimeIndex) and 'tz' in attrs:
+ from pandas.core.indexes.datetimes import _new_DatetimeIndex
+ attrs['data'] = result
+ return _new_DatetimeIndex(self, attrs)
+ else:
+ return Index(result, **attrs)
 
  @cache_readonly
  def dtype(self):

pandas/tests/indexes/datetimes/test_datetime.py

@@ -794,3 +794,19 @@ def test_slice_duplicate_monotonic(self):
  result = idx._maybe_cast_slice_bound('2017-01-01', 'left', 'loc')
  expected = Timestamp('2017-01-01')
  assert result == expected
+
+ def test_split_datetime_index_with_timezone(self):
+ # https://github.com/pandas-dev/pandas/issues/14042
+ # check if timezone is correctly handled in array_wrapper
+ tz = 'Asia/Seoul'
+ index = date_range('2000-01-01', periods=10, freq='D', tz=tz)
+ series = Series(index, np.arange(10))
+ index_split = np.split(index, indices_or_sections=5)
+ series_split = np.split(series, indices_or_sections=5)
+ for i in range(5):
+ index_expected = date_range('2000-01-{0:02d}'.format(2 * i + 1),
+ periods=2, freq='D', tz=tz)
+ series_expected = Series(index_expected,
+ np.arange(2 * i, 2 * i + 2))
+ tm.assert_index_equal(index_split[i], index_expected)
+ tm.assert_series_equal(series_split[i], series_expected)