var app = angular.module('plunker', []);

app.controller('MainCtrl', function($scope) {
  $scope.name = 'World';
});

/**
 * Deep diff between two object, using lodash
 * @param  {Object} object Object compared
 * @param  {Object} base   Object to compare with
 * @return {Object}        Return a new object who represent the diff
 */
function difference(object, base) {
	function changes(object, base) {
		return _.transform(object, function(result, value, key) {
			if (!_.isEqual(value, base[key])) {
				result[key] = (_.isObject(value) && _.isObject(base[key])) ? changes(value, base[key]) : value;
			}
		});
	}
	return changes(object, base);
}

obj1 ={a:1, b:2} 
obj2 ={a:1, b:4}

df = difference(obj1, obj2)

console.log (df)
<!DOCTYPE html>
<html ng-app="plunker">

  <head>
    <meta charset="utf-8" />
    <title>AngularJS Plunker</title>
    <script>document.write('<base href="' + document.location + '" />');</script>
    <link rel="stylesheet" href="style.css" />
    <script data-require="angular.js@1.5.x" src="https://cdnjs.cloudflare.com/ajax/libs/angular.js/1.5.11/angular.min.js" data-semver="1.5.11"></script>
    <script data-require="lodash@*" data-semver="2.3.0" src="https://raw.github.com/lodash/lodash/2.3.0/dist/lodash.js"></script>
    <script src="app.js"></script>
  </head>

  <body ng-controller="MainCtrl">
    <p>Hello {{name}}!</p>
    <a href="http://www.mattzeunert.com/2016/01/28/javascript-deep-equal.html">http://www.mattzeunert.com/2016/01/28/javascript-deep-equal.html</a><br />
    <a href="https://www.samanthaming.com/tidbits/33-how-to-compare-2-objects">https://www.samanthaming.com/tidbits/33-how-to-compare-2-objects</a><br />
   <b><i>this plunk 201811:</i><a href="https://gist.github.com/Yimiprod/7ee176597fef230d1451">https://gist.github.com/Yimiprod/7ee176597fef230d1451</a><br /></b>
    <a href="https://gist.github.com/nicbell/6081098">https://gist.github.com/nicbell/6081098</a><br />
    <a href=""></a><br />
    <a href=""></a><br />
    <a href=""></a><br />
    <a href=""></a><br />
    <a href=""></a><br />
    <a href=""></a><br />
    <a href=""></a><br />
    
  </body>

</html>
/* Put your css in here */