Add a TestCase mixin for enabling caches in tests

By default, disable all caching in tests, to preserve test independence.
In order to enable caching, inherit from CacheSetupMixin, and specify
which cache configuration is needed.

[EV-32]

common/djangoapps/student/tests/test_login.py

@@ -17,6 +17,7 @@ from mock import patch
 from social.apps.django_app.default.models import UserSocialAuth
 
 from external_auth.models import ExternalAuthMap
+from openedx.core.djangolib.testing.utils import CacheIsolationTestCase
 from student.tests.factories import UserFactory, RegistrationFactory, UserProfileFactory
 from student.views import login_oauth_token
 from third_party_auth.tests.utils import (
@@ -28,11 +29,13 @@ from xmodule.modulestore.tests.factories import CourseFactory
 from xmodule.modulestore.tests.django_utils import ModuleStoreTestCase
 
 
-class LoginTest(TestCase):
+class LoginTest(CacheIsolationTestCase):
     '''
     Test student.views.login_user() view
     '''
 
+    ENABLED_CACHES = ['default']
+
     def setUp(self):
         super(LoginTest, self).setUp()
         # Create one user and save it to the database

common/djangoapps/student/tests/test_login_registration_forms.py

@@ -158,7 +158,7 @@ class RegisterFormTest(ThirdPartyAuthTestMixin, UrlResetMixin, SharedModuleStore
     """Test rendering of the registration form. """
 
     URLCONF_MODULES = ['lms.urls']
-    
+
     @classmethod
     def setUpClass(cls):
         super(RegisterFormTest, cls).setUpClass()

common/djangoapps/student/tests/test_reset_password.py

@@ -19,6 +19,7 @@ from django.utils.http import urlsafe_base64_encode, base36_to_int, int_to_base3
 from mock import Mock, patch
 import ddt
 
+from openedx.core.djangolib.testing.utils import CacheIsolationTestCase
 from student.views import password_reset, password_reset_confirm_wrapper, SETTING_CHANGE_INITIATED
 from student.tests.factories import UserFactory
 from student.tests.test_email import mock_render_to_string
@@ -28,11 +29,13 @@ from .test_microsite import fake_microsite_get_value
 
 
 @ddt.ddt
-class ResetPasswordTests(EventTestMixin, TestCase):
+class ResetPasswordTests(EventTestMixin, CacheIsolationTestCase):
     """ Tests that clicking reset password sends email, and doesn't activate the user
     """
     request_factory = RequestFactory()
 
+    ENABLED_CACHES = ['default']
+
     def setUp(self):
         super(ResetPasswordTests, self).setUp('student.views.tracker')
         self.user = UserFactory.create()

common/djangoapps/student/tests/test_user_profile_properties.py

@@ -7,14 +7,17 @@ from django.test import TestCase
 from student.models import UserProfile
 from student.tests.factories import UserFactory
 from django.core.cache import cache
+from openedx.core.djangolib.testing.utils import CacheIsolationTestCase
 
 
 @ddt.ddt
-class UserProfilePropertiesTest(TestCase):
+class UserProfilePropertiesTest(CacheIsolationTestCase):
     """Unit tests for age, gender_display, and level_of_education_display properties ."""
 
     password = "test"
 
+    ENABLED_CACHES = ['default']
+
     def setUp(self):
         super(UserProfilePropertiesTest, self).setUp()
         self.user = UserFactory.create(password=self.password)