Expected a spy, but got Function

backbone.js, jasmine, javascript, marionette

Solution

You need to get into the actual method, which in this case is on the prototype.

describe('When onGivePoints is fired', function () {
    beforeEach(function () {
        spyOn(UsersBoardCollection.prototype, 'restartPolling').andCallThrough();
        app.vent.trigger('onGivePoints');
    });
    it('the board collection should be fetched', function () {
        expect(UsersBoardCollection.prototype.restartPolling).toHaveBeenCalled();
    });
});

Spying on the prototype is a nice trick you can use when you can't get to the actual instance you want to spy on.

Problem

I am trying to implement a test (1) for this module (2). My purpose is to check if the collection is fetched when a particular event is triggered. As you can see from my comment in (2) I get the message `Error: Expected a spy, but got Function.` The module works but the test fails. any ideas? (1) ``` // jasmine test module describe('When onGivePoints is fired', function () { beforeEach(function () { spyOn(this.view.collection, 'restartPolling').andCallThrough(); app.vent.trigger('onGivePoints'); }); it('the board collection should be fetched', function () { expect(this.view.collection.restartPolling).toHaveBeenCalled(); // Error: Expected a spy, but got Function. }); }); ``` (2) ``` // model view module return Marionette.CompositeView.extend({ initialize: function () { this.collection = new UserBoardCollection(); this.collection.startPolling(); app.vent.on('onGivePoints', this.collection.restartPolling); }, // other code }); ```

Original source