Here is a script I wrote a while ago based on an answer from CoreyG that does precisely what you are looking for and just a bit more...
function getScriptFolderTree() {
var thisScript = getThisScriptInDrive();
var names = [];
var Ids = [];
var folder = thisScript.getParents()[0];
while (folder.getName() != "Root"){
names.unshift(folder.getName());
Ids.unshift(folder.getId());
var parents = folder.getParents();
var folder = parents[0];
}
Logger.log('Root/'+names.join().replace(/,/g,'/'));
Ids.unshift(DocsList.getRootFolder().getId());
Logger.log(Ids)
}
function getThisScriptInDrive() {
return DocsList.find("poiuytrezazertyujhgfdsdcvcxyydryfhchfh")[0];
}