mercurial/filemerge.py

--- a/mercurial/filemerge.py	Wed Oct 07 00:01:16 2015 -0700
+++ b/mercurial/filemerge.py	Wed Oct 07 00:24:44 2015 -0700
@@ -231,8 +231,8 @@
 def _symlinkcheck(repo, mynode, orig, fcd, fco, fca, toolconf):
     tool, toolpath, binary, symlink = toolconf
     if symlink:
-        repo.ui.warn(_('warning: internal :merge cannot merge symlinks '
-                       'for %s\n') % fcd.path())
+        repo.ui.warn(_('warning: internal %s cannot merge symlinks '
+                       'for %s\n') % (tool, fcd.path()))
         return False
     return True