grep: display correct user/revision for --all in reverse. Also handle multiple occurrences of the same line by storing linestates in an array instead of a dict, and using difflib to compute the difference between linestates.

#!/bin/sh

HGRCPATH=$HGTMP/.hgrc; export HGRCPATH
echo "[extensions]" >> $HGTMP/.hgrc
echo "mq=" >> $HGTMP/.hgrc

hg init a
cd a

echo 'base' > base
hg ci -Ambase -d '1 0'

hg qnew -mmqbase mqbase

hg qsave
hg qrestore 2