JSFiddle - React, Tailwind, and code Playground

JavaScript

let object1 = {
  id: 1,
  name: 'hello world'
};

let object2 = {
  id: 2,
  name: undefined
};

// merge object 1 with 2:
let objExtend = $.extend({}, object1, object2);
let objAssign = Object.assign({}, object1, object2);

// diff
console.log(objExtend.name); // "hello world"
console.log(objAssign.name); //  undefined