Object.clone literal

/**
* Creates a clone of the input (or this) object.
* To avoid unexpected results, one should not use this function to clone arrays.
* If you want to be able to clone object with null prototype, remove the
* corresponding statement below (see the comments).
* @method clone
* @param {Object} obj
* @returns {Object|Boolean} Returns a new object or false if the input value is not a valid object.
*/
clone: function (obj) {
var donor;
if (obj) {
if (typeof obj !== 'object') {
return false; // not an object
}
donor = obj;
} else {
donor = this;
}
if (!donor.__proto__) { // remove this statement to be able to clone object with __proto__ === null
return false; // has not prototype
}
if (typeof donor.__proto__ !== 'object') {
return false; // prototype is not an object
}
let result = Object.create(donor.__proto__);
for (let key in donor) {
if (!donor.hasOwnProperty(key)) {
continue;
}
result[key] = donor[key];
}
return result;
}