Remove keep_attrs from resample signature (pydata#8444)

doc/whats-new.rst

@@ -47,6 +47,9 @@ Deprecations
   existing methods work and don't raise any warnings, given the relatively small
   benefits of the change.
   By `Maximilian Roos <https://github.com/max-sixty>`_.
+- Finally remove ``keep_attrs`` kwarg from :py:meth:`DataArray.resample` and
+  :py:meth:`Dataset.resample`. These were deprecated a long time ago.
+  By `Deepak Cherian <https://github.com/dcherian>`_.
 
 Bug fixes
 ~~~~~~~~~

xarray/core/common.py

@@ -860,7 +860,6 @@ def _resample(
         base: int | None,
         offset: pd.Timedelta | datetime.timedelta | str | None,
         origin: str | DatetimeLike,
-        keep_attrs: bool | None,
         loffset: datetime.timedelta | str | None,
         restore_coord_dims: bool | None,
         **indexer_kwargs: str,
@@ -989,13 +988,6 @@ def _resample(
         from xarray.core.pdcompat import _convert_base_to_offset
         from xarray.core.resample import RESAMPLE_DIM
 
-        if keep_attrs is not None:
-            warnings.warn(
-                "Passing ``keep_attrs`` to ``resample`` has no effect and will raise an"
-                " error in xarray 0.20. Pass ``keep_attrs`` directly to the applied"
-                " function, e.g. ``resample(...).mean(keep_attrs=True)``."
-            )
-
         # note: the second argument (now 'skipna') use to be 'dim'
         if (
             (skipna is not None and not isinstance(skipna, bool))

xarray/core/dataarray.py

@@ -7021,7 +7021,6 @@ def resample(
         base: int | None = None,
         offset: pd.Timedelta | datetime.timedelta | str | None = None,
         origin: str | DatetimeLike = "start_day",
-        keep_attrs: bool | None = None,
         loffset: datetime.timedelta | str | None = None,
         restore_coord_dims: bool | None = None,
         **indexer_kwargs: str,
@@ -7143,7 +7142,6 @@ def resample(
             base=base,
             offset=offset,
             origin=origin,
-            keep_attrs=keep_attrs,
             loffset=loffset,
             restore_coord_dims=restore_coord_dims,
             **indexer_kwargs,

xarray/core/dataset.py

@@ -10327,7 +10327,6 @@ def resample(
         base: int | None = None,
         offset: pd.Timedelta | datetime.timedelta | str | None = None,
         origin: str | DatetimeLike = "start_day",
-        keep_attrs: bool | None = None,
         loffset: datetime.timedelta | str | None = None,
         restore_coord_dims: bool | None = None,
         **indexer_kwargs: str,
@@ -10404,7 +10403,6 @@ def resample(
             base=base,
             offset=offset,
             origin=origin,
-            keep_attrs=keep_attrs,
             loffset=loffset,
             restore_coord_dims=restore_coord_dims,
             **indexer_kwargs,

xarray/tests/test_groupby.py

@@ -1776,11 +1776,6 @@ def test_resample_keep_attrs(self):
         expected = DataArray([1, 1, 1], [("time", times[::4])], attrs=array.attrs)
         assert_identical(result, expected)
 
-        with pytest.warns(
-            UserWarning, match="Passing ``keep_attrs`` to ``resample`` has no effect."
-        ):
-            array.resample(time="1D", keep_attrs=True)
-
     def test_resample_skipna(self):
         times = pd.date_range("2000-01-01", freq="6H", periods=10)
         array = DataArray(np.ones(10), [("time", times)])
@@ -2138,11 +2133,6 @@ def test_resample_by_mean_with_keep_attrs(self):
         expected = ds.attrs
         assert expected == actual
 
-        with pytest.warns(
-            UserWarning, match="Passing ``keep_attrs`` to ``resample`` has no effect."
-        ):
-            ds.resample(time="1D", keep_attrs=True)
-
     def test_resample_loffset(self):
         times = pd.date_range("2000-01-01", freq="6H", periods=10)
         ds = Dataset(