Fixed #22939 -- Delayed admin_static backend detection

register = Library()

_static = None

@register.simple_tag

def static(path):

    global _static

    if _static is None:

        if apps.is_installed('django.contrib.staticfiles'):

    from django.contrib.staticfiles.templatetags.staticfiles import static

            from django.contrib.staticfiles.templatetags.staticfiles import static as _static

        else:

    from django.templatetags.static import static

static = register.simple_tag(static)

            from django.templatetags.static import static as _static

    return _static(path)

from django.contrib.admin import ModelAdmin

from django.contrib.admin.helpers import ACTION_CHECKBOX_NAME

from django.contrib.admin.models import LogEntry, DELETION

from django.contrib.admin.templatetags.admin_static import static

from django.contrib.admin.templatetags.admin_urls import add_preserved_filters

from django.contrib.admin.tests import AdminSeleniumWebDriverTestCase

from django.contrib.admin.utils import quote

from django.contrib.auth import REDIRECT_FIELD_NAME

from django.contrib.auth.models import Group, User, Permission

from django.contrib.contenttypes.models import ContentType

from django.contrib.staticfiles.storage import staticfiles_storage

from django.forms.utils import ErrorList

from django.template.response import TemplateResponse

from django.test import TestCase, skipUnlessDBFeature

            '/test_admin/%s/admin_views/article/add/' % self.urlbit,

            status_code=301)

    def test_admin_static_template_tag(self):

        """

        Test that admin_static.static is pointing to the collectstatic version

        (as django.contrib.collectstatic is in installed apps).

        """

        old_url = staticfiles_storage.base_url

        staticfiles_storage.base_url = '/test/'

        try:

            self.assertEqual(static('path'), '/test/path')

        finally:

            staticfiles_storage.base_url = old_url

    def test_basic_add_GET(self):

        """

        A smoke test to ensure GET on the add_view works.