Testing routers in backbone.js properly?

Question

So I\'ve just started to write tests for my in-progress javascript app, using sinon.js & jasmine.js. Works pretty well overall, but I need to also

Answer 1

When I'm testing a backbone router, what I care about is that the routes I provided are invoking the functions I specify with the correct arguments. A lot of the other answers here aren't really testing that.

If you need to test the functionality of some routes, you can test those functions by themselves.

Assuming you have a simple router:

App.Router = Backbone.Router.extend({
  routes: {
    '(/)':'index',
    '/item/:id':'item'
  },
  index: {
    //render some template
  }, 
  item: {
    //render some other template, or redirect, or _whatever_
  }
});

Here's how I do it:

describe('Router', function() {

  var trigger = {trigger: true};
  var router

  beforeEach(function() {
    // This is the trick, right here:
    // The Backbone history code dodges our spies
    // unless we set them up exactly like this:
    Backbone.history.stop(); //stop the router
    spyOn(Router.prototype, 'index'); //spy on our routes, and they won't get called
    spyOn(Router.prototype, 'route2'); 

    router = new App.Router(); // Set up the spies _before_ creating the router
    Backbone.history.start();
  });

  it('empty route routes to index', function(){
    Backbone.history.navigate('', trigger);
    expect(router.index).toHaveBeenCalled();
  });

  it('/ routes to index', function(){
    router.navigate('/', trigger);
    expect(router.index).toHaveBeenCalled();
  });

  it('/item routes to item with id', function(){
    router.navigate('/item/someId', trigger);
    expect(router.item).toHaveBeenCalledWith('someId');
  });
});