Adding Cookiecutter-django users urls to i18n_patterns breaks tests

Question

I'm having a problem with tests and internationalization.

• Project is Django 1.11
• Python 3.5
• project created with cookiecutter-django

Internationalization code in settings.py:

TIME_ZONE = 'UTC'

LANGUAGE_CODE = 'en-us'
SITE_ID = 1
USE_I18N = True
USE_L10N = True
USE_TZ = True

LANGUAGES = [
    ('en', _('English')),
    ('fr', _('French')),
    ('es', _('Spanish')),
    ('de', _('German')),
]

Running pytest on the standard Cookiecutter tests for Users, without adding i18n_patterns, successfully completes. Once the urls are updated like this:

urlpatterns += i18n_patterns(
    ....
    # User management
    url(r'^accounts/', include('allauth.urls')),
    url(r'^users/', include('users.urls', namespace='users')),
    ....
)

The url tests then fail. The output looks like this:

======================================================================
FAIL: test_get_redirect_url (users.tests.test_views.TestUserRedirectView)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "users/tests/test_views.py", line 33, in test_get_redirect_url
    '/users/testuser/'
AssertionError: '/en-us/users/testuser/' != '/users/testuser/'
- /en-us/users/testuser/
? ------
+ /users/testuser/

As you can see, the issue is that /en-us/ is the prefix being used on the url. Now, I could fix this by adding /en-us/ to my assertions. However, the /en-us/ prefix is incorrect. This is a language code and not the regular language prefix as shown in my settings file.

Outside of testing, and using runserver, if I navigate to the /users// url it is prefaced with /en/ not /en-us/

So, the big question is why do the tests preface with /en-us/ when i18n_patterns() uses /en/?

Edit Here are the contents of users/tests/test_urls.py

from django.core.urlresolvers import reverse, resolve

from test_plus.test import TestCase


class TestUserURLs(TestCase):
    """Test URL patterns for users app."""

    def setUp(self):
        self.user = self.make_user()

    def test_list_reverse(self):
        """users:list should reverse to /users/."""
        self.assertEqual(reverse('users:list'), '/users/')

    def test_list_resolve(self):
        """/users/ should resolve to users:list."""
        self.assertEqual(resolve('/users/').view_name, 'users:list')

    def test_redirect_reverse(self):
        """users:redirect should reverse to /users/~redirect/."""
        self.assertEqual(reverse('users:redirect'), '/users/~redirect/')

    def test_redirect_resolve(self):
        """/users/~redirect/ should resolve to users:redirect."""
        self.assertEqual(
            resolve('/users/~redirect/').view_name,
            'users:redirect'
        )

    def test_detail_reverse(self):
        """users:detail should reverse to /users/testuser/."""
        self.assertEqual(
            reverse('users:detail', kwargs={'username': 'testuser'}),
            '/users/testuser/'
        )

    def test_detail_resolve(self):
        """/users/testuser/ should resolve to users:detail."""
        self.assertEqual(resolve('/users/testuser/').view_name, 'users:detail')

    def test_update_reverse(self):
        """users:update should reverse to /users/~update/."""
        self.assertEqual(reverse('users:update'), '/users/~update/')

    def test_update_resolve(self):
        """/users/~update/ should resolve to users:update."""
        self.assertEqual(
            resolve('/users/~update/').view_name,
            'users:update'
        )