--- a/mercurial/templater.py	Fri Mar 21 11:06:02 2008 +0100
+++ b/mercurial/templater.py	Fri Mar 21 12:05:01 2008 +0100
@@ -7,6 +7,7 @@
 
 from i18n import _
 import re, sys, os
+from mercurial import util
 
 def parsestring(s, quoted=True):
     '''parse a string using simple c-like syntax.
@@ -55,6 +56,9 @@
 
         if not mapfile:
             return
+        if not os.path.exists(mapfile):
+            raise util.Abort(_('style not found: %s') % mapfile)
+
         i = 0
         for l in file(mapfile):
             l = l.strip()