Debug 400 page now displays special error message if your URLconf is empty.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@1552 bcc190cf-cafb-0310-a4f2-bffc1f526a37

django/views/debug.py

@@ -128,15 +128,21 @@ def technical_404_response(request, exception):
     Create a technical 404 error response.  The exception should be the Http404
     exception.
     """
+    urlconf_is_empty = False
     try:
         tried = exception.args[0]['tried']
     except (IndexError, TypeError):
         tried = []
+    else:
+        if not tried:
+            # tried exists but is an empty list. The URLconf must've been empty.
+            urlconf_is_empty = True
 
     t = Template(TECHNICAL_404_TEMPLATE)
     c = Context({
         'root_urlconf': settings.ROOT_URLCONF,
         'urlpatterns': tried,
+        'urlconf_is_empty': urlconf_is_empty,
         'reason': str(exception),
         'request': request,
         'request_protocol': os.environ.get("HTTPS") == "on" and "https" or "http",
@@ -533,6 +539,9 @@ TECHNICAL_404_TEMPLATE = """
     </table>
   </div>
   <div id="info">
+    {% if urlconf_is_empty %}
+      <p>Your URLconf, <code>{{ settings.ROOT_URLCONF }}</code>, was empty.</p>
+    {% else %}
       {% if urlpatterns %}
         <p>
         Using the URLconf defined in <code>{{ settings.ROOT_URLCONF }}</code>,
@@ -547,6 +556,7 @@ TECHNICAL_404_TEMPLATE = """
       {% else %}
         <p>{{ reason|escape }}</p>
       {% endif %}
+    {% endif %}
   </div>
 
   <div id="explanation">