command line templates: add formatnode filter This will print a full hash node with --debug and a short one otherwise. Use it with some default templates and in map-cmdline.default to print the parents. This should fix issue538.

#!/bin/sh
# http://www.selenic.com/mercurial/bts/issue433

hg init a
cd a       
echo a > a 
hg commit -Ama 

hg parents -r 0 doesnotexist
true