Script that removes slashes from bup backup names

fix-bup-slahes.sh

#!/bin/bash

set -e

if [ "$#" -eq "1" ]; then
    git_dir="$1"
else
    if [ "$#" -eq "0" ]; then
        git_dir="~/.bup"
    else
        echo "usage: $0 [bup-dir]" 1>&2
        exit 1
    fi
fi

git='git --git-dir='"$git_dir"

for branch in $($git for-each-ref --format='%(refname)' refs/heads); do
    branch_name=${branch#refs/heads/}

    if [[ $branch_name =~ / ]]; then
        fixed_branch_name=${branch_name//\//-}

        $git branch "$fixed_branch_name" "$branch_name" > /dev/null
        $git branch -D "$branch_name" > /dev/null

        echo "renamed $branch_name to $fixed_branch_name"
    fi
done