[Thermo] ensure that SolutionArray wraps Solution setters/getters

interfaces/cython/cantera/_cantera.pxd

@@ -141,6 +141,8 @@ cdef extern from "cantera/thermo/ThermoPhase.h" namespace "Cantera":
         # miscellaneous
         string type()
         string report(cbool, double) except +translate_exception
+        cbool isStoichPhase()
+        cbool isIncompressible()
         vector[string] defaultState()
         vector[string] fullStates()
         vector[string] partialStates()

interfaces/cython/cantera/composite.py

@@ -481,6 +481,13 @@ class SolutionArray:
         'transport_model',
     ]
 
+    _all_states = [
+        # all setter/getter combos defined by the ThermoPhase base class
+        'TD', 'TDX', 'TDY', 'TP', 'TPX', 'TPY', 'UV', 'UVX', 'UVY', 
+        'DP', 'DPX', 'DPY', 'HP', 'HPX', 'HPY', 'SP', 'SPX', 'SPY',
+        'SV', 'SVX', 'SVY'
+    ]
+
     _interface_passthrough = ['site_density']
     _interface_n_species = ['coverages']
 
@@ -531,6 +538,7 @@ class SolutionArray:
 
         # add properties dynamically
         state_sets = set(phase._full_states.values()) | set(phase._partial_states.values())
+        state_sets = state_sets | set(self._all_states)
         for name in state_sets:
             ph = type(phase)
             if len(name) == 2:

interfaces/cython/cantera/test/test_models.py

@@ -50,8 +50,9 @@ class TestModels(utilities.CanteraTest):
                 # (converted to errors in test suite)
                 if 'Deprecated' not in str(inst):
 
-                    msg = "Error in processing of phase with type '{}'"
-                    raise TypeError(msg.format(ph['thermo'])) from inst
+                    msg = "Error in processing of phase '{}' with type '{}'"
+                    msg = msg.format(ph['name'], ph['thermo'])
+                    raise TypeError(msg) from inst
 
     def test_restore_thermo_models(self):
 
@@ -75,18 +76,26 @@ class TestModels(utilities.CanteraTest):
 
             try:
                 sol = ct.Solution(yml_file, ph_name)
-
                 a = ct.SolutionArray(sol, 10)
 
                 # assign some state
                 T = 373.15 + 100*np.random.rand(10)
+                P = a.P * (1 + np.random.rand(10))
+                X = a.X
                 if sol.n_species > 1:
-                    X = a.X
                     X[:, 1] = .01
                     X = np.diag(X.sum(axis=1)).dot(X)
-                    a.TPX = T, np.linspace(1., 2., 10), X
+                    self.assertFalse(sol._is_stoich_phase)
+                    self.assertIn('TPX', sol._full_states.values())
+                    a.TPX = T, P, X
                 else:
-                    a.TP = T, np.linspace(1., 2., 10)
+                    a.TP = T, P
+                    if sol._is_stoich_phase:
+                        # filter out thermo phases with ambigious definitions
+                        # (single species, but not defined as stoich substance)
+                        self.assertNotIn('TPX', sol._full_states.values())
+                        with self.assertRaises(AttributeError):
+                            a.TPX = T, P, X
 
                 # default columns
                 data, labels = a.collect_data()
@@ -101,8 +110,9 @@ class TestModels(utilities.CanteraTest):
                 # (converted to errors in test suite)
                 if 'Deprecated' not in str(inst):
 
-                    msg = "Error in processing of phase with type '{}'"
-                    raise TypeError(msg.format(ph['thermo'])) from inst
+                    msg = "Error in processing of phase '{}' with type '{}'"
+                    msg = msg.format(ph['name'], ph['thermo'])
+                    raise TypeError(msg) from inst
 
 
 class TestRestoreIdealGas(utilities.CanteraTest):

interfaces/cython/cantera/thermo.pyx

@@ -285,6 +285,20 @@ cdef class ThermoPhase(_SolutionBase):
     def __call__(self, *args, **kwargs):
         print(self.report(*args, **kwargs))
 
+    property _is_stoich_phase:
+        """
+        Phase represents a stoichiometric (fixed composition) substance
+        """
+        def __get__(self):
+            return self.thermo.isStoichPhase()
+
+    property _is_incompressible:
+        """
+        Phase represents an incompressible substance
+        """
+        def __get__(self):
+            return self.thermo.isIncompressible()
+
     property _default_state:
         """
         Default properties defining a state