I am new to Angular JS.My first question how to understand the error messages from console in Angular JS. I have written this snippet of code for matching passwords. It throws error on console, But it works fine.Its wired. I am not able to understand anything from those console messages. Could anyone please point me out why I am getting error message on console.
var sampleApp = angular.module("sampleApp",[]);
    sampleApp.controller('sampleCtrl', ['$scope', function($scope){
     
    }]);
    sampleApp.directive('pwCheck', [function(){
     // Runs during compile
     return {
      
      require: 'ngModel', // Array = multiple requires, ? = optional, ^ = check parent elements
      
      link: function($scope, iElm, iAttrs, controller) {
       var password1 = iAttrs.ngModel;
       var password2 = iAttrs.pwCheck;
       $scope.$watch('[password1, password2]', function(newValue, oldValue){
       controller.$setValidity('pwmatch', $scope[password1] === $scope[password2] );
      });
      }
     };
    }]);
<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.2.23/angular.min.js"></script>
<html ng-app="sampleApp">
 <head>
 </head>
 <body ng-controller="sampleCtrl">
  <form name="myForm">
   <label for="pw1">Set a password:</label><br />
   <input type="password" id="pw1" name="pw1" ng-model="pw1" /><br />
   <label for="pw2">Confirm the password:</label><br />
   <input type="password" id="pw2" name="pw2" ng-model="pw2" pw-check="pw1" />
   <div class="msg-block" ng-show="myForm.$error"> 
    <span class="msg-error" ng-show="myForm.pw2.$error.pwmatch">Passwords don't match.</span> 
            </div>
  </form>
 </body>
</html>
Is there any easy way/tool to debug Angular JS code, As I am facing a lot of difficulty in understanding the console error messages.
Screenshot of console:
