validate paragraph style names based on list

Another note:

If the parent of style is the document you can tell that the style is in the root of the Paragraph Styles panel.

If not, the parent of that style is a paragraph style group.

Regards,
Uwe Laubender
( Adobe Community Professional )

Here's my approach.

Yet another approach, but a small change to your original script.

1. Change the first line to

var pStyles = app.activeDocument.allParagraphStyles;

This creates an array of all paragraph styles, no matter how deeply they are embedded in style groups.

Then replace your two for-loops with this one:

for (var key in styles) {
  if (styles[key])) {
    foundStyles.push (key);
  } else {
    notFoundStyles.push (key);
	}
}

Peter

I have taken a different approach to the problem. The idea is to try and add the paragraphstyle to the document if we crash while doing so then the style is used(what else can possibly cause the crash) and if it did not crash then the style is unsed. Try the following code.

/*
https://community.adobe.com/t5/indesign-discussions/validate-paragraph-style-names-based-on-list/td-p/13184430

Script to get get a create a collection of used and not used paragraph styles for the input style name collection
To search for styles in groups use / as the path seperator
Pre Requisite:- The script needs an open document
Warning :- No elaborate error checking

Author:- Manan Joshi
Guthub Repo :- https://github.com/Manan-Joshi/InDesign-Scripts.git
*/

function getPStyleGroup(nmCol){
    var pg = app.documents[0]
    for(var i = 0 ; i < nmCol.length - 1; i++){
        pg = pg.paragraphStyleGroups.itemByName(nmCol[i])
        if(!pg.isValid)
            return ""
    }
    return pg
}

function getUsedUnusedStyleFromList(inStyleList, outUsed, outUnused){
    var styleCol = app.documents[0].paragraphStyles
    for(var i = 0; i < inStyleList.length; i++){
        var styleCol = app.documents[0].paragraphStyles
        try{
            var grps = inStyleList[i].split("/")
            if(grps.length > 1)
                styleCol = getPStyleGroup(grps)

            if(styleCol === ""){
                outUnused.push(inStyleList[i])
                continue;
            }
            styleCol.add({name:grps[grps.length - 1]})
            app.documents[0].undo()
            outUnused.push(inStyleList[i])
        }catch(e){
            outUsed.push(inStyleList[i])   
        }
    }
}

var styleList = ["abc/def/PS1", "abc/PS2", "PS3","PS8"]
var used = [], unused = []
getUsedUnusedStyleFromList(styleList, used, unused)
alert("Unused " + unused + " Used " + used)

It works for styles in groups as well. To mention style in group seperate each path with a /

-Manan

Are your styles in groups/folders? The top line only gets toplevel paragraph styles. Also, just take out the second loop and amend the first as so: 

for (var key in styles ) {
          if (pStyles.join().indexOf(styles[key]) != -1){
            foundStyles.push (styles[key]);
 
	  } else {
             notFoundStyles.push(styles[key]);
          }
   }