Fixed #29576 -- Corrected the test client's HTTP_COOKIE header.

django/test/client.py

@@ -277,7 +277,10 @@ class RequestFactory:
         # - REMOTE_ADDR: often useful, see #8551.
         # See http://www.python.org/dev/peps/pep-3333/#environ-variables
         return {
-            'HTTP_COOKIE': self.cookies.output(header='', sep='; '),
+            'HTTP_COOKIE': '; '.join(sorted(
+                '%s=%s' % (morsel.key, morsel.coded_value)
+                for morsel in self.cookies.values()
+            )),
             'PATH_INFO': '/',
             'REMOTE_ADDR': '127.0.0.1',
             'REQUEST_METHOD': 'GET',

tests/test_client_regress/tests.py

@@ -1423,3 +1423,9 @@ class RequestFactoryEnvironmentTests(SimpleTestCase):
         self.assertEqual(request.META.get('SERVER_PORT'), '80')
         self.assertEqual(request.META.get('SERVER_PROTOCOL'), 'HTTP/1.1')
         self.assertEqual(request.META.get('SCRIPT_NAME') + request.META.get('PATH_INFO'), '/path/')
+
+    def test_cookies(self):
+        factory = RequestFactory()
+        factory.cookies.load('A="B"; C="D"; Path=/; Version=1')
+        request = factory.get('/')
+        self.assertEqual(request.META['HTTP_COOKIE'], 'A="B"; C="D"')