Updates to object lifecycle for WeightWindows and WeightWindowGenerators (#2582)

tests/regression_tests/weightwindows/generators/test.py

@@ -28,13 +28,20 @@ def test_ww_generator(run_in_tmpdir):
     energy_bounds = np.linspace(0.0, 1e6, 70)
     particle = 'neutron'
 
+    # include another tally to make sure user-specified tallies and those automaticaly
+    # created by weight window generators can coexist
+    tally = openmc.Tally()
+    ef = openmc.EnergyFilter(energy_bounds)
+    tally.filters = [ef]
+    tally.scores = ['flux']
+    model.tallies = [tally]
+
     wwg = openmc.WeightWindowGenerator(mesh, energy_bounds, particle)
-    wwg.update_parameters = {'ratio' : 5.0, 'threshold': 0.8, 'value' : 'mean'}
+    wwg.update_parameters = {'ratio': 5.0, 'threshold': 0.8, 'value': 'mean'}
 
     model.settings.weight_window_generators = wwg
-    model.export_to_xml()
-
     model.run()
+
     # we test the effectiveness of the update method elsewhere, so
     # just test that the generation happens successfully here
     assert os.path.exists('weight_windows.h5')

tests/unit_tests/weightwindows/test.py

@@ -241,7 +241,21 @@ def test_roundtrip(run_in_tmpdir, model, wws):
         assert(ww_out == ww_in)
 
 
-def test_ww_attrs(run_in_tmpdir, model):
+def test_ww_attrs_python(model):
+    mesh = openmc.RegularMesh.from_domain(model.geometry)
+    lower_bounds = np.ones(mesh.dimension)
+
+    # ensure that creation of weight window objects with default arg values
+    # is successful
+    wws = openmc.WeightWindows(mesh, lower_bounds, upper_bound_ratio=10.0)
+
+    assert wws.energy_bounds == None
+
+    wwg = openmc.WeightWindowGenerator(mesh)
+
+    assert wwg.energy_bounds == None
+
+def test_ww_attrs_capi(run_in_tmpdir, model):
     model.export_to_xml()
 
     openmc.lib.init()