JSFiddle - React, Tailwind, and code Playground

JavaScript

function objectWatch(object) {

    var keys = Object.keys(object);
    return {
        done: function () {
            var o = {
                created: {},
                removed: {}
            },
            newkeys = Object.keys(object);

            if (keys.length === newkeys.length) return;
            if (keys.length > newkeys.length) {
                for (var i = 0, l = keys.length; i < l; i++) {
                    if (newskeys.indexOf(keys[i]) === -1) o.removed[keys[i]] = object[keys[i]];
                }
            }
            for (var i = 0, l = newkeys.length; i < l; i++) {
                if (keys.indexOf(newkeys[i]) === -1) o.created[newkeys[i]] = object[newkeys[i]];

            }

            return o;



        }
    };
}

check = new objectWatch(window);
x = 1;
y = 1;
console.log(check.done());