BUG: date_range doesn't propagate ambigous=False to tz_localize (#35302)

Author: arw2019

doc/source/whatsnew/v1.2.0.rst

@@ -71,7 +71,7 @@ Timedelta
 Timezones
 ^^^^^^^^^
 
--
+- Bug in :func:`date_range` was raising AmbiguousTimeError for valid input with `ambiguous=False` (:issue:`35297`)
 -
 
 

pandas/core/arrays/datetimes.py

@@ -418,9 +418,9 @@ def _generate_range(
  # index is localized datetime64 array -> have to convert
  # start/end as well to compare
  if start is not None:
- start = start.tz_localize(tz).asm8
+ start = start.tz_localize(tz, ambiguous, nonexistent).asm8
  if end is not None:
- end = end.tz_localize(tz).asm8
+ end = end.tz_localize(tz, ambiguous, nonexistent).asm8
  else:
  # Create a linearly spaced date_range in local time
  # Nanosecond-granularity timestamps aren't always correctly

pandas/tests/indexes/datetimes/test_constructors.py

@@ -787,6 +787,65 @@ def test_construction_with_nat_and_tzlocal(self):
  expected = DatetimeIndex([Timestamp("2018", tz=tz), pd.NaT])
  tm.assert_index_equal(result, expected)
 
+ def test_constructor_with_ambiguous_keyword_arg(self):
+ # GH 35297
+
+ expected = DatetimeIndex(
+ ["2020-11-01 01:00:00", "2020-11-02 01:00:00"],
+ dtype="datetime64[ns, America/New_York]",
+ freq="D",
+ ambiguous=False,
+ )
+
+ # ambiguous keyword in start
+ timezone = "America/New_York"
+ start = pd.Timestamp(year=2020, month=11, day=1, hour=1).tz_localize(
+ timezone, ambiguous=False
+ )
+ result = pd.date_range(start=start, periods=2, ambiguous=False)
+ tm.assert_index_equal(result, expected)
+
+ # ambiguous keyword in end
+ timezone = "America/New_York"
+ end = pd.Timestamp(year=2020, month=11, day=2, hour=1).tz_localize(
+ timezone, ambiguous=False
+ )
+ result = pd.date_range(end=end, periods=2, ambiguous=False)
+ tm.assert_index_equal(result, expected)
+
+ def test_constructor_with_nonexistent_keyword_arg(self):
+ # GH 35297
+
+ timezone = "Europe/Warsaw"
+
+ # nonexistent keyword in start
+ start = pd.Timestamp("2015-03-29 02:30:00").tz_localize(
+ timezone, nonexistent="shift_forward"
+ )
+ result = pd.date_range(start=start, periods=2, freq="H")
+ expected = DatetimeIndex(
+ [
+ pd.Timestamp("2015-03-29 03:00:00+02:00", tz=timezone),
+ pd.Timestamp("2015-03-29 04:00:00+02:00", tz=timezone),
+ ]
+ )
+
+ tm.assert_index_equal(result, expected)
+
+ # nonexistent keyword in end
+ end = pd.Timestamp("2015-03-29 02:30:00").tz_localize(
+ timezone, nonexistent="shift_forward"
+ )
+ result = pd.date_range(end=end, periods=2, freq="H")
+ expected = DatetimeIndex(
+ [
+ pd.Timestamp("2015-03-29 01:00:00+01:00", tz=timezone),
+ pd.Timestamp("2015-03-29 03:00:00+02:00", tz=timezone),
+ ]
+ )
+
+ tm.assert_index_equal(result, expected)
+
  def test_constructor_no_precision_raises(self):
  # GH-24753, GH-24739