Is it possible to get the non-enumerable inherited property names of an object?

Question

In JavaScript we have a few ways of getting the properties of an object, depending on what we want to get.

1) Object.keys(), which returns all own, enu

Answer 1

An implementation in my personal preferences :)

function getAllProperties(In, Out = {}) {
    const keys = Object.getOwnPropertyNames(In);
    keys.forEach(key => Object.defineProperty(In, key, {
        enumerable: true
    }));
    Out = { ...In, ...Out };

    const Prototype = Object.getPrototypeOf(In);
    return Prototype === Object.prototype ? Out : getAllProperties(Proto, Out);
}