bash prompt - colourful git status

.bashrc

# got it via http://aussie.lunix.com.au/blog/2013/02/08/coloured-git-status-in-your-bash-prompt/
# put into .bashrc or .bash_profile

function _git_prompt() {
    local git_status="`git status -unormal 2>&1`"
    if ! [[ "$git_status" =~ Not\ a\ git\ repo ]]; then
        if [[ "$git_status" =~ nothing\ to\ commit ]]; then
            local ansi=32
        elif [[ "$git_status" =~ nothing\ added\ to\ commit\ but\ untracked\ files\ present ]]; then
            local ansi=34
        else
            local ansi=33
        fi  
        echo -n '\[\e[0;33;'"$ansi"'m\]'"$(__git_ps1)"'\[\e[0m\]'
    fi
}

function _prompt_command() {
  PS1="[\[\033[32m\]\w\[\033[0m\]]\[\033[0m\]\n\[\033[1;36m\]\u@\[\033[0;37m\]\h] `_git_prompt` \[\033[1;33m\]-> \[\033[0m\]"
}

PROMPT_COMMAND=_prompt_command

# if you get 
# -bash: __git_ps1: command not found 
# error do 
# $ curl https://raw.github.com/git/git/master/contrib/completion/git-prompt.sh > ~/.bash_git 
# and add 
# source ~/.bash_git 
# above this code