Author contribution stats (+/-) [with git and awk]

git-stats.sh

# /bin/sh

IFS=$'\n'
authors=$(git log --format='%aN' | sort -u)

for author in $authors
do
	echo $author | awk 'BEGIN { FS = "\" " }; { printf "%-20s ", $1 }'
	git log --author="$author" --pretty=tformat: --numstat |
	awk '{ add += $1; subs += $2; edits += $1 + $2 } END { printf "%10d (+) %10s (-) %10s (+/-) \n", add, subs, edits }'
done