My function is returning list of empty object a

You must add the objects to the array with the method push, like this:

objlist=[];
for(file in files){
    obj = {};
    obj.file = file;
    //... do all stuff with obj
    objlist.push(obj);
}

Also your function is asynchronous inside the fs.readdir, so if you have to build and populate in the function or do an await to receive the result.

Otherwise you will call the function, it will be executed asynchronously, you will continue at the main function without the wait of the response of the fs.readdir and the array will continue empty because you async function may or may not have been executed.

There are two mistakes in your code:-

1) You are using an array as an object

2) Since for loop is synchronous loop and you are trying asynchronous task inside it and hence either use synchronous version of fs or change your for loop as follows:-

for(file in files) {
    obj = {};
    obj[file]={};
    (function(f){
                fs.stat(path + '\\' + files[f], function(err,stats){
                    if(err)
                        throw err;
                    if(stats.isDirectory()){
                        obj[file]['file'] = 'folder'
                    }
                    if(stats.isFile()){
                        obj[file]['file'] = 'file'
                    }
                    obj[file]['name'] = files[file]
                    obj[file]['size'] = stats.size
                    objlist.push(obj)
                    //console.log(objlist)
                    //console.log(stats)

                });
            }
    }(file))
}