Fix the remaining module storage tests.

lms/djangoapps/courseware/model_data.py

@@ -25,7 +25,7 @@ def chunks(items, chunk_size):
 class ModelDataCache(object):
     """
     A cache of django model objects needed to supply the data
-    for a module and its decendents
+    for a module and its decendants
     """
     def __init__(self, descriptors, course_id, user, select_for_update=False):
         '''
@@ -35,10 +35,10 @@ class ModelDataCache(object):
         state will have a StudentModule.
 
         Arguments
-        descriptors: An array of XModuleDescriptors.
+        descriptors: A list of XModuleDescriptors.
         course_id: The id of the current course
         user: The user for which to cache data
-        select_for_update: Flag indicating whether the rows should be locked until end of transaction
+        select_for_update: True if rows should be locked until end of transaction
         '''
         self.cache = {}
         self.descriptors = descriptors

lms/djangoapps/courseware/tests/test_model_data.py

@@ -131,7 +131,8 @@ class TestStudentModuleStorage(TestCase):
 
     def setUp(self):
         self.desc_md = {}
-        self.user = UserFactory.create()
+        student_module = StudentModuleFactory(state=json.dumps({'a_field': 'a_value'}))
+        self.user = student_module.student
         self.mdc = ModelDataCache([mock_descriptor([mock_field(Scope.student_state, 'a_field')])], course_id, self.user)
         self.kvs = LmsKeyValueStore(self.desc_md, self.mdc)
 
@@ -159,7 +160,7 @@ class TestStudentModuleStorage(TestCase):
         "Test that deleting an existing field removes it from the StudentModule"
         self.kvs.delete(student_state_key('a_field'))
         self.assertEquals(1, StudentModule.objects.all().count())
-        self.assertEquals({}, self.mdc.find.return_value.state)
+        self.assertRaises(KeyError, self.kvs.get, student_state_key('not_a_field'))
 
     def test_delete_missing_field(self):
         "Test that deleting a missing field from an existing StudentModule raises a KeyError"