Prints the ahead and behind status for each tracked branch.

git-branch-status.sh

#!/bin/bash
# Adapted from https://stackoverflow.com/a/7774433/2045006

git for-each-ref --format="%(refname:short) %(upstream:short)" refs/heads | \
while read local remote
do
    [ -z "$remote" ] && continue
    git rev-list --left-right ${local}...${remote} -- 2>/dev/null >/tmp/git_upstream_status_delta || continue
    LEFT_AHEAD=$(grep -c '^<' /tmp/git_upstream_status_delta)
    RIGHT_AHEAD=$(grep -c '^>' /tmp/git_upstream_status_delta)
    echo -e "\033[32m$local\033[00m...\033[31m$remote\033[00m [ahead \033[32m$LEFT_AHEAD\033[00m] [behind \033[31m$RIGHT_AHEAD\033[00m]"
done