Fixed #6681 -- Don't break docutils when rendering reStructuredText.

Don't set a global default interpreted role function for reStructuredText.
Instead, use the `default-role` directive to change the default only within
the `parse_rst()` function.

Thanks Malcolm Tredinnick for the report.

django/contrib/admindocs/utils.py

@@ -67,9 +67,18 @@ def parse_rst(text, default_reference_context, thing_being_parsed=None):
     }
     if thing_being_parsed:
         thing_being_parsed = force_bytes("<%s>" % thing_being_parsed)
-    parts = docutils.core.publish_parts(text, source_path=thing_being_parsed,
-                destination_path=None, writer_name='html',
-                settings_overrides=overrides)
+    # Wrap ``text`` in some reST that sets the default role to ``cmsreference``,
+    # then restores it.
+    source = """
+.. default-role:: cmsreference
+
+%s
+
+.. default-role::
+"""
+    parts = docutils.core.publish_parts(source % text,
+                source_path=thing_being_parsed, destination_path=None,
+                writer_name='html', settings_overrides=overrides)
     return mark_safe(parts['fragment'])
 
 #
@@ -100,7 +109,6 @@ def default_reference_role(name, rawtext, text, lineno, inliner, options=None, c
 
 if docutils_is_available:
     docutils.parsers.rst.roles.register_canonical_role('cmsreference', default_reference_role)
-    docutils.parsers.rst.roles.DEFAULT_INTERPRETED_ROLE = 'cmsreference'
 
     for name, urlbase in ROLES.items():
         create_reference_role(name, urlbase)

tests/admin_docs/tests.py

+import unittest
+
+try:
+    import docutils
+except ImportError:
+    docutils = None
+
+from django.contrib.admindocs import utils
 from django.contrib.auth.models import User
 from django.test import TestCase
 from django.test.utils import override_settings
@@ -43,3 +51,39 @@ class XViewMiddlewareTest(TestCase):
         user.save()
         response = self.client.head('/xview/class/')
         self.assertFalse('X-View' in response)
+
+
+@unittest.skipUnless(docutils, "no docutils installed.")
+class DefaultRoleTest(TestCase):
+    urls = 'admin_docs.urls'
+
+    def test_parse_rst(self):
+        """
+        Tests that ``django.contrib.admindocs.utils.parse_rst`` uses
+        ``cmsreference`` as the default role.
+        """
+        markup = ('<p><a class="reference external" href="/admindocs/%s">'
+                  'title</a></p>\n')
+        self.assertEqual(utils.parse_rst('`title`', 'model'),
+                         markup % 'models/title/')
+        self.assertEqual(utils.parse_rst('`title`', 'view'),
+                         markup % 'views/title/')
+        self.assertEqual(utils.parse_rst('`title`', 'template'),
+                         markup % 'templates/title/')
+        self.assertEqual(utils.parse_rst('`title`', 'filter'),
+                         markup % 'filters/#title')
+        self.assertEqual(utils.parse_rst('`title`', 'tag'),
+                         markup % 'tags/#title')
+
+    def test_publish_parts(self):
+        """
+        Tests that Django hasn't broken the default role for interpreted text
+        when ``publish_parts`` is used directly, by setting it to
+        ``cmsreference``. See #6681.
+        """
+        self.assertNotEqual(docutils.parsers.rst.roles.DEFAULT_INTERPRETED_ROLE,
+                            'cmsreference')
+        source = 'reST, `interpreted text`, default role.'
+        markup = '<p>reST, <cite>interpreted text</cite>, default role.</p>\n'
+        parts = docutils.core.publish_parts(source=source, writer_name="html4css1")
+        self.assertEqual(parts['fragment'], markup)

tests/admin_docs/urls.py

-from django.conf.urls import patterns
+from django.conf.urls import include, patterns
 
 from . import views
 
 urlpatterns = patterns('',
+    (r'^admindocs/', include('django.contrib.admindocs.urls')),
     (r'^xview/func/$', views.xview_dec(views.xview)),
     (r'^xview/class/$', views.xview_dec(views.XViewClass.as_view())),
 )