Javascript Unit testing dependencies - How to make a test fail when a depended object changes

Question

I have a controller which is depended on a model property. I wrote a test which test this controller and stubbed the model, How can I make my controller test fail whenever the model property name changes?

Here is an example:

Model:

function Model(obj){
  this.id = obj.id; 
  this.name = obj.name;
}

Controller:

function Controller( model ){
  this.model = model
};
Controller.prototype.showName = function() { 
  return this.model.name; 
}

Controller test:

describe("A controller", function(){

  var controller = new Controller( new Model({id:1, name: "john"}) );

  it ("should show the person name", function(){
    expect(controller.showName).toEqual("john");
  });

});

I want this test to fail whenever the "name" property changes to something else, something like "name2".

Anyone got a good suggestion on how to do it in javascript?

Thanks, Shai

Answer 1

Since the model is exposed you can check for the existence of the property.

expect(controller.name).toBeDefined();

On the other hand, this test would fail anyway if the property of the model was renamed and the controller wouldn't be altered too.