Angularjs testing: using $broadcast doesn't fill variables as expected

In my scenerio I do the following:

1) Grab data from socket
2) Raise an event $scope.$broadcast('socket:newData', data)
3) Watch it in the directive:

$scope.processedData = [];
$scope.$on('socket:newData', function(e,data){
  // gets data processed, and adds it to $scope.processedData
  myService.dataProcess($scope.processedData, data);
});

In the app it works fine and I get the data. In my test I define $rootScope and $compile. The directive builds nicely and I do some tests for its isolated scope as well as HTML and everything seems to be in order (including templates and subdirectives loading).

The problem is: $scope.prcessedData remains empty.

Here is my test code:

beforeEach(module('app'));

beforeEach(_inject(function(_$rootScope_, _$compile_, _myService_){
  $rootScope = _$rootScope_;
  $compile - _$compile_;
  myService = _myService_;
  element = angular.element('<my-directive></my-directive>');
  $compile(element)($rootScope);
}));

beforeEach(function(){
  spyOn(myService, 'dataProcess');
  var data = getMockData(); // returns some data sample that's in the format of the data recieved from the socket
  $rootScope.$broadcast('socket:newData', data);
  $rootScope.$apply();
    });

it('Processed data should be filled', function(){
  // *getExpected* returns the expected processed data  
  expect(element.isolateScope().processedData).toEqual(getExpected(getMockData()));
});

But element.isolateScope().processedData returns []...

I've tried the following to make sure the processing function runs its course:

it('Expect the function "dataProcess" to run', function(){
  expect(myService.dataProcess).toHaveBeenCalledWith(element.isolateScope().processedData, getMockData());
});

Which passes and still element.isolateScope().processedData returns []...

How can I retrieve the values after the function has run its course?