Fixed #16866 -- Clearer error message if empty list is passed to sele…

…ct_template. Thanks Silver_Ghost for report and patch.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@16861 bcc190cf-cafb-0310-a4f2-bffc1f526a37

django/template/loader.py

@@ -179,6 +179,8 @@ def render_to_string(template_name, dictionary=None, context_instance=None):
 
 def select_template(template_name_list):
     "Given a list of template names, returns the first that can be loaded."
+    if not template_name_list:
+        raise TemplateDoesNotExist("No template names provided")
     not_found = []
     for template_name in template_name_list:
         try:

tests/regressiontests/templates/loaders.py

@@ -143,5 +143,16 @@ def test_existing_context_kept_clean(self):
         self.assertEqual(output, 'obj:after')
         self.assertEqual(context['obj'], 'before')
 
+    def test_empty_list(self):
+        self.assertRaisesRegexp(TemplateDoesNotExist,
+                                'No template names provided$',
+                                loader.render_to_string, [])
+
+
+    def test_select_templates_from_empty_list(self):
+        self.assertRaisesRegexp(TemplateDoesNotExist,
+                                'No template names provided$',
+                                loader.select_template, [])
+
 if __name__ == "__main__":
     unittest.main()