gistfile1.sh

#!/bin/bash

MY_S=( )

main() {

  local current
  local branch=${1}
  local branches
  local idx=0
  local quick

  if [ "$(git rev-parse --git-dir 2>/dev/null)" = "" ]; then
    echo "Not a git repository"
    exit 1
  fi  

  if [ "${branch}" = "" ]; then
    echo -e "\nPlease specify a branch (showing latest):\n"
    #echo -e $(echo ${MY_S[@]:0} | sed 's/ /\\n/g')

    while [ ${idx} -lt ${#MY_S[@]} ]; do
      echo ${idx}. ${MY_S[${idx}]}
      ((idx++))
    done

    exit 1
  fi  

  current=$(git symbolic-ref HEAD | sed 's/refs\/heads\///')

  if [[ "${branch}" =~ ^[0-9]$ ]]; then
    branch=${MY_S[${branch}]}
    if [ "${branch}" = "" ]; then
      echo "What!?"
      exit 1
    fi  
  fi  

  if [ "${current}" = "${branch}" ]; then
    echo "You already are on ${branch}"
    exit 1
  fi  

  git checkout ${branch}

  if [ $? -eq 0 ]; then
    if [ "${branch}" = "-" ]; then
      exit 0
    fi  
    if [ ${#MY_S[@]} -eq 5 ]; then
      unset MY_S[0]
    fi  
    MY_S[${#MY_S[@]}+1]=${branch}
    branches=${MY_S[@]:0}
    $(sed -i "s/^MY_S=\(.*\)/MY_S=( ${branches} )/g" ${0})
  fi  

}

main $1