Only use ModelGroup.details if python-ihm supports it

Author: benmwebb

modelcif/dumper.py

@@ -641,7 +641,10 @@ def dump_model_groups(self, system, writer):
     def dump_model_group_summary(self, system, writer):
         with writer.loop("_ma_model_group", ["id", "name", "details"]) as lp:
             for group in system.model_groups:
-                lp.write(id=group._id, name=group.name, details=group.details)
+                # ihm.model.ModelGroup only supports details after v1.8
+                lp.write(id=group._id, name=group.name,
+                         details=group.details
+                         if hasattr(group, 'details') else None)
 
     def dump_model_group_link(self, system, writer):
         with writer.loop("_ma_model_group_link",

test/test_dumper.py

@@ -434,8 +434,9 @@ class CustomModel(modelcif.model.Model):
         system.model_groups.append(mg)
         # model1 is in both groups
         mg = modelcif.model.ModelGroup((model1,),
-                                       name='second group',
-                                       details='second group details')
+                                       name='second group')
+        # ModelGroup constructor only supports details with python-ihm > 1.8
+        mg.details = 'second group details'
         system.model_groups.append(mg)
         dumper = modelcif.dumper._ModelDumper()
         dumper.finalize(system)