--- a/tests/test-command-template.t	Tue Mar 18 14:29:33 2014 -0700
+++ b/tests/test-command-template.t	Mon Mar 31 10:12:07 2014 -0500
@@ -1439,6 +1439,12 @@
   abort: template filter 'datefilter' is not compatible with keyword 'author'
   [255]
 
+Thrown an error if a template function doesn't exist
+
+  $ hg tip --template '{foo()}\n'
+  hg: parse error: unknown function 'foo'
+  [255]
+
   $ cd ..