Question

I’m getting a bunch of test errors in my django project. They are caused by adding ‘django.contrib.messages’ to INSTALLED_APPS. Has anyone seen these before?

# python manage.py test
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ERROR: test_middleware_disabled_anon_user (django.contrib.messages.tests.cookie.CookieTest)
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Traceback (most recent call last):
  File "/Users/so/Code/freshplum/env/orchard/lib/python2.7/site-packages/django/contrib/messages/tests/base.py", line 284, in test_middleware_disabled_anon_user
    'django.contrib.messages.context_processors.messages',
ValueError: list.remove(x): x not in list

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ERROR: test_middleware_disabled_anon_user_fail_silently (django.contrib.messages.tests.cookie.CookieTest)
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Traceback (most recent call last):
  File "/Users/so/Code/freshplum/env/orchard/lib/python2.7/site-packages/django/contrib/messages/tests/base.py", line 313, in test_middleware_disabled_anon_user_fail_silently
    'django.contrib.messages.context_processors.messages',
ValueError: list.remove(x): x not in list

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ERROR: test_middleware_disabled_auth_user (django.contrib.messages.tests.cookie.CookieTest)
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Traceback (most recent call last):
  File "/Users/so/Code/freshplum/env/orchard/lib/python2.7/site-packages/django/contrib/messages/tests/base.py", line 250, in test_middleware_disabled_auth_user
    'django.contrib.messages.context_processors.messages',
ValueError: list.remove(x): x not in list

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ERROR: test_middleware_disabled_anon_user (django.contrib.messages.tests.fallback.FallbackTest)
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Traceback (most recent call last):
  File "/Users/so/Code/freshplum/env/orchard/lib/python2.7/site-packages/django/contrib/messages/tests/base.py", line 284, in test_middleware_disabled_anon_user
    'django.contrib.messages.context_processors.messages',
ValueError: list.remove(x): x not in list

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ERROR: test_middleware_disabled_anon_user_fail_silently (django.contrib.messages.tests.fallback.FallbackTest)
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Traceback (most recent call last):
  File "/Users/so/Code/freshplum/env/orchard/lib/python2.7/site-packages/django/contrib/messages/tests/base.py", line 313, in test_middleware_disabled_anon_user_fail_silently
    'django.contrib.messages.context_processors.messages',
ValueError: list.remove(x): x not in list

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ERROR: test_middleware_disabled_auth_user (django.contrib.messages.tests.fallback.FallbackTest)
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Traceback (most recent call last):
  File "/Users/so/Code/freshplum/env/orchard/lib/python2.7/site-packages/django/contrib/messages/tests/base.py", line 250, in test_middleware_disabled_auth_user
    'django.contrib.messages.context_processors.messages',
ValueError: list.remove(x): x not in list

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ERROR: test_middleware_disabled_anon_user (django.contrib.messages.tests.user_messages.LegacyFallbackTest)
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Traceback (most recent call last):
  File "/Users/so/Code/freshplum/env/orchard/lib/python2.7/site-packages/django/contrib/messages/tests/base.py", line 284, in test_middleware_disabled_anon_user
    'django.contrib.messages.context_processors.messages',
ValueError: list.remove(x): x not in list

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ERROR: test_middleware_disabled_anon_user_fail_silently (django.contrib.messages.tests.user_messages.LegacyFallbackTest)
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Traceback (most recent call last):
  File "/Users/so/Code/freshplum/env/orchard/lib/python2.7/site-packages/django/contrib/messages/tests/base.py", line 313, in test_middleware_disabled_anon_user_fail_silently
    'django.contrib.messages.context_processors.messages',
ValueError: list.remove(x): x not in list

======================================================================
ERROR: test_middleware_disabled_auth_user (django.contrib.messages.tests.user_messages.LegacyFallbackTest)
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Traceback (most recent call last):
  File "/Users/so/Code/freshplum/env/orchard/lib/python2.7/site-packages/django/contrib/messages/tests/base.py", line 250, in test_middleware_disabled_auth_user
    'django.contrib.messages.context_processors.messages',
ValueError: list.remove(x): x not in list

======================================================================
ERROR: test_middleware_disabled_anon_user (django.contrib.messages.tests.session.SessionTest)
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Traceback (most recent call last):
  File "/Users/so/Code/freshplum/env/orchard/lib/python2.7/site-packages/django/contrib/messages/tests/base.py", line 284, in test_middleware_disabled_anon_user
    'django.contrib.messages.context_processors.messages',
ValueError: list.remove(x): x not in list

======================================================================
ERROR: test_middleware_disabled_anon_user_fail_silently (django.contrib.messages.tests.session.SessionTest)
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Traceback (most recent call last):
  File "/Users/so/Code/freshplum/env/orchard/lib/python2.7/site-packages/django/contrib/messages/tests/base.py", line 313, in test_middleware_disabled_anon_user_fail_silently
    'django.contrib.messages.context_processors.messages',
ValueError: list.remove(x): x not in list

======================================================================
ERROR: test_middleware_disabled_auth_user (django.contrib.messages.tests.session.SessionTest)
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Traceback (most recent call last):
  File "/Users/so/Code/freshplum/env/orchard/lib/python2.7/site-packages/django/contrib/messages/tests/base.py", line 250, in test_middleware_disabled_auth_user
    'django.contrib.messages.context_processors.messages',
ValueError: list.remove(x): x not in list

Answer 1

You’ve added the app to INSTALLED_APPS, but you haven’t added the relevant context processor to TEMPLATE_CONTEXT_PROCESSORS – it needs to include "django.contrib.messages.context_processors.messages".