A (very) brief introduction to Jasmine and how to apply it to Backbone applications.

1. Testing Backbone
applications with Jasmine
Leon van der Grient
2014

2. You know you should

3. Why?
Confidence

4. What?
Unitsbehavior

5. When?
BeforeDuringAfter

6. How?
• qUnit
• SinonJS
• Mocha
• Jasmine

7. Behavior Driven Testing
"Users should be able to like a message"

8. Test suite
|
* Spec
|
* Expectations

9. describe("Users should be able to", function () {
// Your specs
});

10. describe("Users should be able to", function () {
it("like a message", function () {
var a = 1;
var b = 2;
var c = a + b;
expect(c).toEqual(3);
expect(c).not.toEqual(4);
});
});

11. Spies and mocks
spyOn($, "ajax");
$.ajax(arg);
!
expect($).toHaveBeenCalled();
expect($).toHaveBeenCalledWith(arg);
expect($.calls.count()).toEqual(1);

12. But there is more!
spyOn($, "ajax").and.callFake(function () {
// mock ajax call
var response = {
success: true,
data: {...}
};
arguments[0].success(response);
});

14. Models
Collections
Views

15. Testing models
it("like a message", function () {
this.message.set({liked:false});
this.message.like();
expect(this.message.get('liked').toBeTruthy();
});

16. Testing views
it("like a message", function () {
this.message.set({liked:false});
this.view.likeMessage();
expect(this.message.get('liked').toBeTruthy();
});

17. Using mocks
spyOn($, "ajax").and.callFake(function () {
// mock ajax call
var response = {
success: true,
data: {...}
};
arguments[0].success(response);
});

18. Test for triggers
it("like a message", function () {
var spy = jasmine.createSpy();
this.view.listenTo(this.model, "change",
spy);
this.view.likeMessage();
expect(spy).toHaveBeenCalled();
});

19. Test user interaction with jasmine-jquery plugin
it("follow a user", function () {
var followBtn = $('.follow-btn');
followBtn.click();
expect(followBtn).toHaveClass("unfollow");
});

20. (too) many tests
toBeInDOM()
toBeVisible()
toHaveAttr()
toHaveClass()
toHaveText()
toHaveValue()
toBeChecked()
toBeDisabled()

21. Results

23. Again, what?
• Methods
• The el property
• Events
• ...?