add correction for tuples + correct error in quantity if tuples outputed

Author: rcaneill

gsw_xarray/_core.py

@@ -16,8 +16,9 @@
 
 
 def add_attrs(rv, attrs, name):
-    rv.name = name
-    rv.attrs = attrs
+    if isinstance(rv, xr.DataArray):
+        rv.name = name
+        rv.attrs = attrs
 
 
 def pint_compat(args, kwargs):
@@ -68,14 +69,13 @@ def cf_attrs_wrapper(*args, **kwargs):
                 for (i, da) in enumerate(rv):
                     add_attrs(da, attrs_checked[i], name[i])
                     if is_quantity:
-                        da = rv.pint.quantify()
-                        rv_updated.append(da)
+                        rv_updated.append(da.pint.quantify())
                     else:
                         rv_updated.append(da)
 
                 rv = tuple(rv_updated)
 
-            elif isinstance(rv, xr.DataArray):
+            else:
                 add_attrs(rv, attrs_checked, name)
                 if is_quantity:
                     rv = rv.pint.quantify()

gsw_xarray/tests/test_gsw_xarray.py

@@ -1,6 +1,7 @@
 from gsw_xarray import __version__
 import gsw_xarray as gsw
 import xarray as xr
+import numpy as np
 import pytest
 
 
@@ -22,6 +23,12 @@ def test_func_return_tuple(ds):
     assert CT_SA.attrs["units"] == "K/(g/kg)"
 
 
+def test_func_return_tuple_ndarray(ds):
+    (CT_SA, CT_pt) = gsw.CT_first_derivatives(ds.SA.data, 1)
+    assert isinstance(CT_SA, np.ndarray)
+    assert isinstance(CT_pt, np.ndarray)
+
+
 @pytest.mark.parametrize("gsdh", [0, 1, None])
 @pytest.mark.parametrize("ssg", [0, 1, None])
 @pytest.mark.parametrize(

gsw_xarray/tests/test_units.py

@@ -71,3 +71,9 @@ def test_xarray_quantity_or_ds(ds, ds_pint, SA_type, CT_type):
     else:
         assert sigma0.pint.units is None
         assert sigma0.pint.quantify().pint.units == pint_xarray.unit_registry("kg / m^3")
+
+
+def test_func_return_tuple_quantity(ds_pint):
+    pint_xarray = pytest.importorskip("pint_xarray")
+    (CT_SA, CT_pt) = gsw_xarray.CT_first_derivatives(ds_pint.SA, 1)
+    assert CT_SA.pint.units == pint_xarray.unit_registry("K/(g/kg)")