JS取得した位置は、現在のスクリプトを実行します

var whereAmI = function(){
    var jsPath = document.currentScript ? document.currentScript.src : function(){
        var js = document.scripts
            ,last = js.length - 1
            ,src;
        for(var i = last; i > 0; i--){
            if(js[i].readyState === 'interactive'){
                src = js[i].src;
                break;
            }
        }
        return src || js[last].src;
    }();
    return jsPath.substring(0, jsPath.lastIndexOf('/') + 1);
}();