Merge remote-tracking branch 'upstream/master' into df_set_index_warn

Author: h-vetinari

ci/travis-27.yaml

@@ -44,7 +44,7 @@ dependencies:
  # universal
  - pytest
  - pytest-xdist
- - moto
+ - moto==1.3.4
  - hypothesis>=3.58.0
  - pip:
  - backports.lzma

doc/source/whatsnew/v0.24.0.txt

@@ -824,6 +824,7 @@ Groupby/Resample/Rolling
 - Bug in :meth:`Resampler.asfreq` when frequency of ``TimedeltaIndex`` is a subperiod of a new frequency (:issue:`13022`).
 - Bug in :meth:`SeriesGroupBy.mean` when values were integral but could not fit inside of int64, overflowing instead. (:issue:`22487`)
 - :func:`RollingGroupby.agg` and :func:`ExpandingGroupby.agg` now support multiple aggregation functions as parameters (:issue:`15072`)
+- Bug in :meth:`DataFrame.resample` and :meth:`Series.resample` when resampling by a weekly offset (``'W'``) across a DST transition (:issue:`9119`, :issue:`21459`)
 
 Sparse
 ^^^^^^

pandas/core/resample.py

@@ -16,7 +16,8 @@
 from pandas.tseries.frequencies import to_offset, is_subperiod, is_superperiod
 from pandas.core.indexes.datetimes import DatetimeIndex, date_range
 from pandas.core.indexes.timedeltas import TimedeltaIndex
-from pandas.tseries.offsets import DateOffset, Tick, Day, delta_to_nanoseconds
+from pandas.tseries.offsets import (DateOffset, Tick, Day,
+ delta_to_nanoseconds, Nano)
 from pandas.core.indexes.period import PeriodIndex
 from pandas.errors import AbstractMethodError
 import pandas.core.algorithms as algos
@@ -1395,18 +1396,21 @@ def _get_time_bins(self, ax):
  def _adjust_bin_edges(self, binner, ax_values):
  # Some hacks for > daily data, see #1471, #1458, #1483
 
- bin_edges = binner.asi8
-
  if self.freq != 'D' and is_superperiod(self.freq, 'D'):
- day_nanos = delta_to_nanoseconds(timedelta(1))
  if self.closed == 'right':
- bin_edges = bin_edges + day_nanos - 1
+ # GH 21459, GH 9119: Adjust the bins relative to the wall time
+ bin_edges = binner.tz_localize(None)
+ bin_edges = bin_edges + timedelta(1) - Nano(1)
+ bin_edges = bin_edges.tz_localize(binner.tz).asi8
+ else:
+ bin_edges = binner.asi8
 
  # intraday values on last day
  if bin_edges[-2] > ax_values.max():
  bin_edges = bin_edges[:-1]
  binner = binner[:-1]
-
+ else:
+ bin_edges = binner.asi8
  return binner, bin_edges
 
  def _get_time_delta_bins(self, ax):

pandas/tests/test_resample.py

@@ -2114,6 +2114,28 @@ def test_downsample_across_dst(self):
  freq='H'))
  tm.assert_series_equal(result, expected)
 
+ def test_downsample_across_dst_weekly(self):
+ # GH 9119, GH 21459
+ df = DataFrame(index=DatetimeIndex([
+ '2017-03-25', '2017-03-26', '2017-03-27',
+ '2017-03-28', '2017-03-29'
+ ], tz='Europe/Amsterdam'),
+ data=[11, 12, 13, 14, 15])
+ result = df.resample('1W').sum()
+ expected = DataFrame([23, 42], index=pd.DatetimeIndex([
+ '2017-03-26', '2017-04-02'
+ ], tz='Europe/Amsterdam'))
+ tm.assert_frame_equal(result, expected)
+
+ idx = pd.date_range("2013-04-01", "2013-05-01", tz='Europe/London',
+ freq='H')
+ s = Series(index=idx)
+ result = s.resample('W').mean()
+ expected = Series(index=pd.date_range(
+ '2013-04-07', freq='W', periods=5, tz='Europe/London'
+ ))
+ tm.assert_series_equal(result, expected)
+
  def test_resample_with_nat(self):
  # GH 13020
  index = DatetimeIndex([pd.NaT,