decojs/Specs/Modules/for_spa/for_whenContext/when_subscribing_to_events.js

Scalable frontend architecture

describe("when subscribing to events", [
  'deco/spa/whenContext',
  'deco/proclaimWhen'
], function(
  whenContext,
  proclaimWhen
){

  var event,
    when;

  beforeEach(function(){
    event = proclaimWhen.create(function(){});

    when = whenContext();
  });

  describe("when a child context subscribes to the event", function(){

    var spy;

    because(function(){

      spy = sinon.spy();

      when(event, spy);

      event();
    });

    it("should notify the subscriber", function(){
      expect(spy.callCount).toBe(1);
    });

    describe("when the child context is destroyed", function(){

      because(function(){
        spy.reset();

        whenContext.destroyChildContexts();

        event();
      });

      it("should no longer notify the subscriber", function(){
        expect(spy.callCount).toBe(0);
      });
    });

    describe("when the child context unsubscribes from the event", function(){

      because(function(){
        spy.reset();

        when(event).dont(spy);

        event();
      });

      it("should no longer notify the subscriber", function(){
        expect(spy.callCount).toBe(0);
      });
    });
  });

});