Test flox kwargs

Author: dcherian

xarray/tests/__init__.py

@@ -78,6 +78,8 @@ def _importorskip(modname, minversion=None):
 has_cartopy, requires_cartopy = _importorskip("cartopy")
 has_pint, requires_pint = _importorskip("pint")
 has_numexpr, requires_numexpr = _importorskip("numexpr")
+has_flox, requires_flox = _importorskip("flox")
+
 
 # some special cases
 has_scipy_or_netCDF4 = has_scipy or has_netCDF4

xarray/tests/test_groupby.py

@@ -17,6 +17,7 @@
     assert_identical,
     create_test_data,
     requires_dask,
+    requires_flox,
     requires_scipy,
 )
 
@@ -928,6 +929,17 @@ def test_groupby_dataset_assign():
     assert_identical(actual, expected)
 
 
+@requires_flox
+@pytest.mark.parametrize("kwargs", [{"method": "map-reduce"}, {"engine": "numpy"}])
+def test_groupby_flox_kwargs(kwargs):
+    ds = Dataset({"a": ("x", range(5))}, {"c": ("x", [0, 0, 1, 1, 1])})
+    with xr.set_options(use_flox=False):
+        expected = ds.groupby("c").mean()
+    with xr.set_options(use_flox=True):
+        actual = ds.groupby("c").mean(**kwargs)
+    assert_identical(expected, actual)
+
+
 class TestDataArrayGroupBy:
     @pytest.fixture(autouse=True)
     def setup(self):