Addressed pull request feedback.

common/lib/xmodule/xmodule/modulestore/tests/django_utils.py

@@ -14,6 +14,22 @@ class ModuleStoreTestCase(TestCase):
     collection with templates before running the TestCase
     and drops it they are finished. """
 
+    def update_course(self, course, data):
+        """
+        Updates the version of course in the mongo modulestore
+        with the metadata in data and returns the updated version.
+        """
+
+        store = xmodule.modulestore.django.modulestore()
+
+        store.update_item(course.location, data)
+
+        store.update_metadata(course.location, data)
+
+        updated_course = store.get_instance(course.id, course.location)
+
+        return updated_course
+
     @staticmethod
     def flush_mongo_except_templates():
         '''

common/lib/xmodule/xmodule/modulestore/tests/factories.py

@@ -60,6 +60,8 @@ class XModuleCourseFactory(Factory):
         if data is not None:
             store.update_item(new_course.location, data)
 
+        '''update_item updates the the course as it exists in the modulestore, but doesn't
+        update the instance we are working with, so have to refetch the course after updating it.'''
         new_course = store.get_instance(new_course.id, new_course.location)
 
         return new_course
@@ -150,6 +152,8 @@ class XModuleItemFactory(Factory):
         if new_item.location.category not in DETACHED_CATEGORIES:
             store.update_children(parent_location, parent.children + [new_item.location.url()])
 
+        '''update_children updates the the item as it exists in the modulestore, but doesn't
+        update the instance we are working with, so have to refetch the item after updating it.'''
         new_item = store.get_item(new_item.location)
 
         return new_item