Accessing session in middleware causes contrib.auth tests to fail

[Tomek Paczkowski]

I have custom middleware that looks like this:

class MyMiddleware:
    def process_request(self, request):
        if request.user.is_authenticated():
            pass # not important

After adding to MIDDLEWARE_CLASSES this causes following error to appear in tests:

FAIL: test_session_not_accessed (django.contrib.auth.tests.context_processors.AuthContextProcessorTests)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/home/oinopion/Devel/django/django/contrib/auth/tests/context_processors.py", line 31, in test_session_not_accessed
    self.assertContains(response, "Session not accessed")
  File "/home/oinopion/Devel/django/django/test/testcases.py", line 524, in assertContains
    msg_prefix + "Couldn't find '%s' in response" % text)
AssertionError: False is not True : Couldn't find 'Session not accessed' in response

[Aymeric Augustin]

This was reported in #16366.