#!/usr/bin/env bash

export USAGE='[<base>]'

# This is the recommended pattern from `man git-sh-setup`.
#
# shellcheck disable=SC1090
. "$(git --exec-path)/git-sh-setup"

set -euo pipefail

case "$#" in
    0)
        base=$(git remote show origin | grep "HEAD branch" | awk '{ print $3 }')
        ;;
    1)
        base="$1"
        ;;
    *) usage ;;
esac

git branch --list --format='%(refname:short)' \
    | xargs -t -n 1 git rebase "${base}"