title: Testing $broadcast event
body: <p>I have a problem with angular tests. I'm trying to test that $broadcast was successfully fired. I'm having some strange behavior trying to use spyOn. If you have any suggestions please help I've been trying to solve this for hours. My test looks like this: </p>
  
  <pre><code>describe('Signup controller', function() {
  
    beforeEach(module('myApp'));
  
    describe('SignupCtrl', function(){
      var $scope, ctrl, $httpBackend, AUTH_EVENTS, $rootScope;
  
      beforeEach(inject(function($injector, $controller,
        _$httpBackend_, _apiUrl_, _AUTH_EVENTS_){
  
          $rootScope = $injector.get('$rootScope');
          $scope = $rootScope.$new();
          ctrl = $controller('SignupCtrl', {$scope: $scope});
          $httpBackend = _$httpBackend_;
          apiUrl = _apiUrl_;
          AUTH_EVENTS = _AUTH_EVENTS_;
          spyOn($rootScope, "$broadcast");
        }
      ));
  
      afterEach(function() {
        $httpBackend.verifyNoOutstandingExpectation();
        $httpBackend.verifyNoOutstandingRequest();
      });
  
      it('should show error message from API', function() {
        var apiMessage = 'That email already exists.';
        $httpBackend.expectPOST('/users').respond(400, {
          message: apiMessage
        });
  
        // call controller register function with mock empty credentials
        $scope.register({});
  
        $httpBackend.flush();
        expect($rootScope.$broadcast).toHaveBeenCalledWith(AUTH_EVENTS.signupFailed);
        expect($scope.errorMessage).toBe(apiMessage);
        expect($scope.showErrorMessage).toBe(true);
      });
  
    });
  });
  </code></pre>
  
  <p>And the error I'm getting is:</p>
  
  <pre><code>TypeError: 'undefined' is not an object (evaluating '$rootScope.$broadcast('$locationChangeStart', $location.absUrl(), oldUrl).
              defaultPrevented')
    at /src/web/src/vendor-bower/angular/angular.js:9789
    at /src/web/src/vendor-bower/angular/angular.js:12595
    at /src/web/src/vendor-bower/angular/angular.js:12407
    at /src/web/src/vendor-bower/angular-mocks/angular-mocks.js:1438
  </code></pre>