Question

I execute a method in the Backbone’s View initialize method.

initialize : function(options) {
      this.myMethod();
   }

I am trying to spy on this method using sinon like:

this.spyMyMethod = sinon.spy(this.view, "myMethod");

end then

it('should call my method', function(){
  expect(this.spyMyMethod).toHaveBeenCalledOnce();
});

but the test fails…

Any ideas?

Answer 1

You are spying on the method too late.

Wherever you are assigning this.view I assume it is from a call like new Views.SomeView(). It is that new call that will make the initialize function be executed.

Update

I don’t really recommend doing this because it is pretty messy, but you can possibly do something like the following: (I don’t know sinon but this is how you would do it with the base jasmine spy objects)

it('should call my method', function(){
  var dummyView = new Views.SomeView();
  spyOn(dummyView, "myMethod");
  spyOn(Views, "SomeView").andCallFake(function () {
    dummyView.initialize();
    return dummyView;
  });
  new Views.SomeView();
  expect(dummyView.myMethod).toHaveBeenCalled();
});

Another Possiblilty

Looks like it might be possible to override that method with a spy like below. If that works, it is probably the cleanest way to do this.

it('should call my method', function(){
  spyOn(Views.SomeView.prototype, "myMethod");
  new Views.SomeView();
  expect(Views.SomeView.prototype.myMethod).toHaveBeenCalled();
});