also check use_bottleneck in ffill and bfill

Author: keewis

xarray/core/missing.py

@@ -12,7 +12,7 @@
 from .common import _contains_datetime_like_objects, ones_like
 from .computation import apply_ufunc
 from .duck_array_ops import datetime_to_numeric, push, timedelta_to_numeric
-from .options import _get_keep_attrs
+from .options import OPTIONS, _get_keep_attrs
 from .pycompat import dask_version, is_duck_dask_array
 from .utils import OrderedSet, is_scalar
 from .variable import Variable, broadcast_variables
@@ -405,6 +405,9 @@ def _bfill(arr, n=None, axis=-1):
 
 def ffill(arr, dim=None, limit=None):
     """forward fill missing values"""
+    if not OPTIONS["use_bottleneck"]:
+        raise RuntimeError("ffill requires bottleneck to be enabled")
+
     axis = arr.get_axis_num(dim)
 
     # work around for bottleneck 178
@@ -422,6 +425,9 @@ def ffill(arr, dim=None, limit=None):
 
 def bfill(arr, dim=None, limit=None):
     """backfill missing values"""
+    if not OPTIONS["use_bottleneck"]:
+        raise RuntimeError("bfill requires bottleneck to be enabled")
+
     axis = arr.get_axis_num(dim)
 
     # work around for bottleneck 178

xarray/tests/test_missing.py

@@ -392,6 +392,30 @@ def test_ffill():
     assert_equal(actual, expected)
 
 
+def test_ffill_use_bottleneck():
+    da = xr.DataArray(np.array([4, 5, np.nan], dtype=np.float64), dims="x")
+    with xr.set_options(use_bottleneck=False):
+        with pytest.raises(RuntimeError):
+            da.ffill("x")
+
+    da = da.chunk({"x": 1})
+    with xr.set_options(use_bottleneck=False):
+        with pytest.raises(RuntimeError):
+            da.ffill("x")
+
+
+def test_bfill_use_bottleneck():
+    da = xr.DataArray(np.array([4, 5, np.nan], dtype=np.float64), dims="x")
+    with xr.set_options(use_bottleneck=False):
+        with pytest.raises(RuntimeError):
+            da.bfill("x")
+
+    da = da.chunk({"x": 1})
+    with xr.set_options(use_bottleneck=False):
+        with pytest.raises(RuntimeError):
+            da.bfill("x")
+
+
 @requires_bottleneck
 @requires_dask
 @pytest.mark.parametrize("method", ["ffill", "bfill"])