Remove the create_user argument to setUp.

Instead, use a class attribute to define test behavior. This allows for
easier addition of new mixins over time.

common/djangoapps/third_party_auth/tests/utils.py

@@ -26,9 +26,11 @@ class ThirdPartyOAuthTestMixin(ThirdPartyAuthTestMixin):
     access_token = "test_access_token"
     client_id = "test_client_id"
 
-    def setUp(self, create_user=True):
+    CREATE_USER = True
+
+    def setUp(self):
         super(ThirdPartyOAuthTestMixin, self).setUp()
-        if create_user:
+        if self.CREATE_USER:
             self.user = UserFactory()
             UserSocialAuth.objects.create(user=self.user, provider=self.BACKEND, uid=self.social_uid)
         self.oauth_client = self._create_client()

common/djangoapps/util/tests/test_keyword_sub_utils.py

@@ -17,8 +17,10 @@ from util import keyword_substitution as Ks
 class KeywordSubTest(ModuleStoreTestCase):
     """ Tests for the keyword substitution feature """
 
+    CREATE_USER = False
+
     def setUp(self):
-        super(KeywordSubTest, self).setUp(create_user=False)
+        super(KeywordSubTest, self).setUp()
         self.user = UserFactory.create(
             email="testuser@edx.org",
             username="testuser",

common/djangoapps/util/tests/test_milestones_helpers.py

@@ -18,11 +18,13 @@ class MilestonesHelpersTestCase(ModuleStoreTestCase):
     Main test suite for Milestones API client library
     """
 
+    CREATE_USER = False
+
     def setUp(self):
         """
         Test case scaffolding
         """
-        super(MilestonesHelpersTestCase, self).setUp(create_user=False)
+        super(MilestonesHelpersTestCase, self).setUp()
         self.course = CourseFactory.create(
             metadata={
                 'entrance_exam_enabled': True,

common/djangoapps/util/tests/test_organizations_helpers.py

@@ -14,11 +14,13 @@ class OrganizationsHelpersTestCase(ModuleStoreTestCase):
     Main test suite for Organizations API client library
     """
 
+    CREATE_USER = False
+
     def setUp(self):
         """
         Test case scaffolding
         """
-        super(OrganizationsHelpersTestCase, self).setUp(create_user=False)
+        super(OrganizationsHelpersTestCase, self).setUp()
         self.course = CourseFactory.create()
 
         self.organization = {

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

@@ -383,16 +383,16 @@ class ModuleStoreTestCase(TestCase):
     """
 
     MODULESTORE = mixed_store_config(mkdtemp_clean(), {})
+
+    CREATE_USER = True
+
     # Tell Django to clean out all databases, not just default
     multi_db = True
 
-    def setUp(self, **kwargs):
+    def setUp(self):
         """
-        Creates a test User if `create_user` is True.
-        Returns the password for the test User.
-
-        Args:
-            create_user - specifies whether or not to create a test User.  Default is True.
+        Creates a test User if `self.CREATE_USER` is True.
+        Sets the password as self.user_password.
         """
         settings_override = override_settings(MODULESTORE=self.MODULESTORE)
         settings_override.__enter__()
@@ -422,11 +422,11 @@ class ModuleStoreTestCase(TestCase):
 
         uname = 'testuser'
         email = 'test+courses@edx.org'
-        password = 'foo'
+        self.user_password = 'foo'
 
-        if kwargs.pop('create_user', True):
+        if self.CREATE_USER:
             # Create the user so we can log them in.
-            self.user = User.objects.create_user(uname, email, password)
+            self.user = User.objects.create_user(uname, email, self.user_password)
 
             # Note that we do not actually need to do anything
             # for registration if we directly mark them active.
@@ -436,7 +436,6 @@ class ModuleStoreTestCase(TestCase):
             self.user.is_staff = True
             self.user.save()
 
-        return password
 
     def create_non_staff_user(self):
         """