#!/usr/bin/env bash

old=$1
new=$2

test -z "$old" && echo "old tag name required." 1>&2 && exit 1
test -z "$new" && echo "new tag name required." 1>&2 && exit 1

git tag "$new" "$old"
git tag -d "$old"
git push origin "$new"
git push origin ":refs/tags/$old"