Fixed #23933 -- Made override_settings(DATABASE_ROUTERS) affect the master router.

django/test/signals.py

@@ -4,7 +4,8 @@ import threading
 import warnings
 
 from django.conf import settings
-from django.db import connections
+from django.db import connections, router
+from django.db.utils import ConnectionRouter
 from django.dispatch import receiver, Signal
 from django.utils import timezone
 from django.utils.functional import empty
@@ -77,6 +78,12 @@ def update_connections_time_zone(**kwargs):
             conn.cursor().execute(tz_sql, [tz])
 
 
+@receiver(setting_changed)
+def clear_routers_cache(**kwargs):
+    if kwargs['setting'] == 'DATABASE_ROUTERS':
+        router.routers = ConnectionRouter().routers
+
+
 @receiver(setting_changed)
 def reset_default_template_engine(**kwargs):
     if kwargs['setting'] in {

docs/releases/1.8.txt

@@ -500,6 +500,9 @@ Tests
   for Oracle: :setting:`DATAFILE`, :setting:`DATAFILE_TMP`,
   :setting:`DATAFILE_MAXSIZE` and :setting:`DATAFILE_TMP_MAXSIZE`.
 
+* The :func:`~django.test.override_settings` decorator can now affect the
+  master router in :setting:`DATABASE_ROUTERS`.
+
 Validators
 ^^^^^^^^^^
 

tests/test_utils/tests.py

@@ -6,7 +6,7 @@ import unittest
 from django.conf.urls import url
 from django.core.files.storage import default_storage
 from django.core.urlresolvers import NoReverseMatch, reverse
-from django.db import connection
+from django.db import connection, router
 from django.forms import EmailField, IntegerField
 from django.http import HttpResponse
 from django.template.loader import render_to_string
@@ -842,3 +842,11 @@ class OverrideSettingsTests(TestCase):
         self.assertIsNone(default_storage.directory_permissions_mode)
         with self.settings(FILE_UPLOAD_DIRECTORY_PERMISSIONS=0o777):
             self.assertEqual(default_storage.directory_permissions_mode, 0o777)
+
+    def test_override_database_routers(self):
+        """
+        Overriding DATABASE_ROUTERS should update the master router.
+        """
+        test_routers = (object(),)
+        with self.settings(DATABASE_ROUTERS=test_routers):
+            self.assertSequenceEqual(router.routers, test_routers)