Observing failing test ( don't understand something ??? )

observes_test.js

test("Observes data...  ", function() {

  var count = 0;

  //var model = SC.IO.Resource.create({
  var model = SC.Object.create({
    data: null

  });

  SC.addObserver(model, 'data', function() { count++; });

  var data = [{ "id": 5 }, {"id":6}];


  SC.run( function(){

    //model.updateData(data);
    set(model, 'data', data);

  });
  equals(count, 1, 'should have invoked observer ');

  SC.run( function(){

    //model.updateData(data);
    set(model, 'data', data);

  });
  equals(count, 2, 'should have invoked observer again ');


});