Libraries to stringify extendScript objects?

#target illustrator
function test () {

	"object"!=typeof JSON&&(JSON={}),function(){"use strict";function f(t){return 10>t?"0"+t:t}function quote(t){
		return escapable.lastIndex=0,escapable.test(t)?'"'+t.replace(escapable,function(t){var e=meta[t];
			return"string"==typeof e?e:"\\u"+("0000"+t.charCodeAt(0).toString(16)).slice(-4)})+'"':'"'+t+'"'}
		function str(t,e){var n,r,o,f,u,i=gap,p=e[t];switch(p&&"object"==typeof p&&"function"==typeof p.toJSON&&(p=p.toJSON(t)),
			"function"==typeof rep&&(p=rep.call(e,t,p)),typeof p){case"string":return quote(p);case"number":return isFinite(p)?String(p):"null";
		case"boolean":case"null":return String(p);case"object":if(!p)return"null";if(gap+=indent,u=[],"[object Array]"===Object.prototype.toString.apply(p)){
			for(f=p.length,n=0;f>n;n+=1)u[n]=str(n,p)||"null";return o=0===u.length?"[]":gap?"[\n"+gap+u.join(",\n"+gap)+"\n"+i+"]":"["+u.join(",")+"]",gap=i,o}
				if(rep&&"object"==typeof rep)for(f=rep.length,n=0;f>n;n+=1)"string"==typeof rep[n]&&(r=rep[n],o=str(r,p),o&&u.push(quote(r)+(gap?": ":":")+o));
			else for(r in p)Object.prototype.hasOwnProperty.call(p,r)&&(o=str(r,p),o&&u.push(quote(r)+(gap?": ":":")+o));return o=0===u.length?"{}":gap?"{\n"+gap+
			u.join(",\n"+gap)+"\n"+i+"}":"{"+u.join(",")+"}",gap=i,o}}"function"!=typeof Date.prototype.toJSON&&(Date.prototype.toJSON=function(){
				return isFinite(this.valueOf())?this.getUTCFullYear()+"-"+f(this.getUTCMonth()+1)+"-"+f(this.getUTCDate())+"T"+f(this.getUTCHours())+":"+
				f(this.getUTCMinutes())+":"+f(this.getUTCSeconds())+"Z":null},String.prototype.toJSON=Number.prototype.toJSON=Boolean.prototype.toJSON=function(){
					return this.valueOf()});var cx,escapable,gap,indent,meta,rep;"function"!=typeof JSON.stringify&&
			(escapable=/[\\\"\x00-\x1f\x7f-\x9f\u00ad\u0600-\u0604\u070f\u17b4\u17b5\u200c-\u200f\u2028-\u202f\u2060-\u206f\ufeff\ufff0-\uffff]/g,
				meta={"\b":"\\b","  ":"\\t","\n":"\\n","\f":"\\f","\r":"\\r",'"':'\\"',"\\":"\\\\"},JSON.stringify=function(t,e,n){var r;
					if(gap="",indent="","number"==typeof n)for(r=0;n>r;r+=1)indent+=" ";else"string"==typeof n&&(indent=n);if(rep=e,
						e&&"function"!=typeof e&&("object"!=typeof e||"number"!=typeof e.length))throw new Error("JSON.stringify");return str("",{"":t})}),
			"function"!=typeof JSON.parse&&(cx=/[\u0000\u00ad\u0600-\u0604\u070f\u17b4\u17b5\u200c-\u200f\u2028-\u202f\u2060-\u206f\ufeff\ufff0-\uffff]/g,
				JSON.parse=function(text,reviver){function walk(t,e){var n,r,o=t[e];if(o&&"object"==typeof o)for(n in o)Object.prototype.hasOwnProperty.call(o,n)&&
				(r=walk(o,n),void 0!==r?o[n]=r:delete o[n]);return reviver.call(t,e,o)}var j;if(text=String(text),cx.lastIndex=0,cx.test(text)&&
					(text=text.replace(cx,function(t){return"\\u"+("0000"+t.charCodeAt(0).toString(16)).slice(-4)})),
					/^[\],:{}\s]*$/.test(text.replace(/\\(?:["\\\/bfnrt]|u[0-9a-fA-F]{4})/g,"@")
						.replace(/"[^"\\\n\r]*"|true|false|null|-?\d+(?:\.\d*)?(?:[eE][+\-]?\d+)?/g,"]")
						.replace(/(?:^|:|,)(?:\s*\[)+/g,"")))return j=eval("("+text+")"),"function"==typeof reviver?walk({"":j},""):j;
				throw new SyntaxError("JSON.parse")})}();

	function ArtNode (typename, name, note, children, extraProps) {
		this.typename = typename;
		this.name = name;
		this.note = note;
		if (typename == "GroupItem") {
			this.children = children || [];
		}
		if (extraProps) {
			for (var all in extraProps) {
				this[all] = extraProps[all];
			}
		}
	};
	function getArtTree (rootArt) {
		function getNodeInfo (art) {
			var thisTypename = art.typename;
			var extraProps = null;
			switch (thisTypename) {
				case "TextFrame":
					extraProps = { "contents" : art.contents };
					break;
				case "SymbolItem":
					extraProps = { "symbol_name" : art.symbol.name };
					break;
				default:
					break;
			}
			var children = null;
			if (thisTypename == "GroupItem") {
				children = [];
				var thisPageItem, newObj;
				for (var i = 0; i < art.pageItems.length; i++) {
					thisPageItem = art.pageItems[i];
					newObj = getNodeInfo(thisPageItem);
					children.push(newObj);
				}
			}
			var thisNode = new ArtNode(
				thisTypename,
				art.name,
				art.note,
				children,
				extraProps
			);
			return thisNode;
		};
		return getNodeInfo(rootArt);
	};
	var doc = app.activeDocument;
	var sel = doc.selection[0];
	var treeObj = getArtTree(sel);
	alert(JSON.stringify(treeObj, null, 2));
};
test();​

{
  "typename": "GroupItem",
  "name": "",
  "note": "",
  "children": [
    {
      "typename": "GroupItem",
      "name": "",
      "note": "",
      "children": [
        {
          "typename": "TextFrame",
          "name": "MyText",
          "note": "",
          "contents": "hey!"
        },
        {
          "typename": "GroupItem",
          "name": "SpecialGroup",
          "note": "",
          "children": [
            {
              "typename": "GroupItem",
              "name": "",
              "note": "",
              "children": [
                {
                  "typename": "PathItem",
                  "name": "",
                  "note": "Note here."
                },
                {
                  "typename": "SymbolItem",
                  "name": "",
                  "note": "",
                  "symbol_name": "Gerbera"
                }
              ]
            },
            {
              "typename": "PathItem",
              "name": "",
              "note": ""
            }
          ]
        },
        {
          "typename": "GroupItem",
          "name": "",
          "note": "",
          "children": [
            {
              "typename": "PathItem",
              "name": "",
              "note": "A note."
            },
            {
              "typename": "PathItem",
              "name": "MyRect",
              "note": "MyRect's note."
            }
          ]
        }
      ]
    },
    {
      "typename": "CompoundPathItem",
      "name": "",
      "note": ""
    }
  ]
}

One approach could be to do it via SVG.

You can export/import SVGs to the filesystem, or you may be able to take advantage of a clipboard hack...

When you copy a selection to the clipboard in Illustrator it serialises it to SVG.

As far as I can tell illustrator doesn't provide a method to directly access the clipboard contents (although there are some workarounds on Windows to do this), but what you should be able to do is create a temporary textframe on the document and paste the clipboard contents into its content property, then read the content back into your javascript to get the raw SVG text.

To paste the SVG back into the file you'd do the reverse.

Copying the text to the clipboard may be a bit tricky, but there seem to be a few discussions about how to do it, like this one: https://community.adobe.com/t5/illustrator/is-it-possible-to-copy-text-to-the-clipboard-in-illustrator-via-javascript/td-p/3424658/page/2?page=1

Do you mean using JSON.stringify for any object within a JSX file, or using JSON.stringify on specific objects like app? If the latter there shouldn't be a need to grab every single property and method of a given native object. What are you actually trying to achieve?

What code gives you the stack overrun error?