Auto workon/deactivate a python virtualenv

auto-ve

function has_virtualenv() {
    if [[ $PWD == $PROJECT_HOME* ]]; then
        PRJCT_NAME=$(echo ${PWD//$PROJECT_HOME/} | cut -f 2 -d /)
        if [ -n "$PRJCT_NAME" ]; then
            if [ -e $WORKON_HOME/$PRJCT_NAME ]; then
                if [ -z "$VIRTUAL_ENV" ]; then
                    workon $PRJCT_NAME
                fi
                return
            fi
        fi
    fi
    if [ -n "$VIRTUAL_ENV" ]; then
        deactivate &> /dev/null
    fi
}

function venv_cd() {
    cd "$@" && has_virtualenv
}

alias cd="venv_cd"