[Python] Fix unordered SolutionArray append

Author: ischoegl

interfaces/cython/cantera/composite.py

@@ -815,14 +815,14 @@ def append(self, state=None, normalize=True, **kwargs):
                     "the thermodynamic state".format(tuple(kwargs))
                 ) from None
             if normalize or attr.endswith("Q"):
-                setattr(self._phase, attr, list(kwargs.values()))
+                setattr(self._phase, attr, [kwargs[a] for a in attr])
             else:
                 if attr.endswith("X"):
                     self._phase.set_unnormalized_mole_fractions(kwargs.pop("X"))
                 elif attr.endswith("Y"):
                     self._phase.set_unnormalized_mass_fractions(kwargs.pop("Y"))
                 attr = attr[:-1]
-                setattr(self._phase, attr, list(kwargs.values()))
+                setattr(self._phase, attr, [kwargs[a] for a in attr])
 
         self._append(self._phase.state, extra_temp)
         self._indices.append(len(self._indices))

test/python/test_composite.py

@@ -475,6 +475,16 @@ def test_append_no_norm_data(self):
         assert states[0].P == gas.P
         assert states[0].Y == approx(gas.Y)
 
+    def test_append_scrambled_input(self):
+        gas = ct.Solution("h2o2.yaml")
+        gas.TP = 300, ct.one_atm
+        gas.set_unnormalized_mass_fractions(np.full(gas.n_species, 0.3))
+        states = ct.SolutionArray(gas)
+        states.append(Y=gas.Y, P=gas.P, normalize=False, T=gas.T)
+        assert states[0].T == gas.T
+        assert states[0].P == gas.P
+        assert states[0].Y == approx(gas.Y)
+
     @pytest.mark.skipif("native" not in ct.hdf_support(),
                         reason="Cantera compiled without HDF support")
     def test_import_no_norm_data(self):