Node.js - Cannot read property 'isDirectory' of undefined

I tried to run this small node test app but when I try to use the stat method from the fs module, it keeps on throwing the same error as - cannot read property 'isDirectory' of undefined

var http = require("http");
var fileSys = require("fs");

http.createServer(function(req, res) {
    if(req.statusCode != 404) {
        fileSys.readdir("templates", function(error, folders) {
            if(!error) {
                for (var i in folders) {
                    fileSys.stat(folders[i], function(error, stats) {
                        if(!error) {
                           res.writeHead("200", {"Content-type": "text/plain"});
                           res.end(stats.isDirectory());
                        } else {
                            console.log(error);
                            return;
                        }
                    });
                }
            } else {
                console.log(error);
                return;
            }
        });
    }
}).listen(8080);


console.log("Server started.......");
console.log("Server running on  loopback:8080 ;)");

then I ran the code twice with and without admin privileges but the problem still persists and the error shows up