this is a spy test double in javascript

stub_spy.js

//original Code
function HttpAuthenticator($http){
  this.load = (){
      return $http.get('/api/login')
  };
}
 
var Authenticator = new HttpAuthenticator();
 
//the controller which will attempt to log in when it is loaded
angular.module('app').controller(function(Authenticator){
     
     Authenticator.load().then(function(dto){
         if(dto.authenticationSuccessful){
             $scope.showLoggedInPanel = true;//we want to test this value is set
         }
     })
   
});


//Stub Test Double - returns something
function AuthenticatorSuccessStub(){
  this.load = function(){
      return $.when({authenticationSuccessful:true;});
  };
}


//Spy Test Double - sets something
function AuthenticatorSpy(){
  var loadedCalled = false;
  this.load = function(){
      loadedCalled = true;
      return $.when({});
  };
}