JSFiddle - React, Tailwind, and code Playground
JavaScript
var data1 = '{"foo": 123, "test":"foo"}';
var data2 = '{"bar": 456, "test":"bar"}';
var json1 = JSON.parse(data1);
var json2 = JSON.parse(data2);
var obj = $.merge({},json1,json2);
console.log(obj);