git-closest-match

#!/bin/sh
# find the closest match from all (or a limited amount) of the reachable trees to a specified tree (where tree is referenced by it's checksum)
# very useful to process the results of `git fsck --unreachable | cut -d\  -f3`

spec=$1
mode=${2:-diff} # num: number of lines or diff: actual diff/log message?
range=${3:-30} # 'all' or most recent <num> in current branch?. 'all' can be quite slow
if [ "$range" = 'all' ]; then
	all=`git rev-list --all | awk '/^commit/ {print $NF}'`
else
	all=`git log -n $range | awk '/^commit/ {print $NF}'`
fi

commit=`for i in $all; do
	echo -n "$i "
	# why is there no git diff --shortnumstat ?
	git diff -M $spec $i | wc -l
done | sort -k 2 -n | head -n 1 | cut -f 1 -d ' '`
if [ "$mode" = diff ]; then
	git log --no-walk $commit | cat -
	git diff -M $spec $commit | cat -
else
	echo -n "$commit: "
	 git diff -M $spec $commit | wc -l
fi