Retrieve all property names for JavaScript object including non enumerables

getAllPropertyNames.js

function getAllPropertyNames(obj) {
    var props = {};

    do {
        Object.getOwnPropertyNames(obj).forEach(function (prop) {
            if (prop !== 'constructor') {
                props[prop] = undefined;
            }
        });
    } while ((obj = Object.getPrototypeOf(obj)) !== Object.prototype);

    return Object.getOwnPropertyNames(props);
}