Testing JS - In Rails

Transcript

1. Testing JavaScript in Rails?
2. Hey JavaScript developers… how do you feel about testing?
5. What’s a Test?
6. Unit Test vs. Feature Test
7. Feature Testing Acceptance Test Written from the perspective of a user clicking around an application Where multiple modules or sections of code are combined and tested as a group Integration Testing Where the smallest testable part of an application is tested. Unit Testing
8. Why is Testing JS hard?
9. Unit & Integration Testing
11. An ‘all in one package’ for testing. You’ve seen it when you do Exercisms. Jasmine A ‘simple, flexible, fun’ testing framework - meaning you have to include utility libraries like Chai for things like ‘assertions’ Mocha Testing Frameworks
12. Given a certain input, give a certain output.
13. The DOM
17. Two Potential Fixes A function that takes in a value, such as an idea’s existing quality and returns a value, such as the idea’s new promoted value Treating Idea as a ‘class’ or ‘object’, separate from the DOM, and testing that our function changes that object when called
18. The Asset Pipeline
19. The Asshat Pipeline
20. The Asset Pipeline
21. Two different gems maintained by the Jasmine Core team/Justin Searls that specifically integrate Jasmine and Rails Jasmine Gem or Jasmine Rails Teaspoon is a bridge that lets your JavaScript testing framework of choice hook into the Asset Pipeline. As a bonus, it includes many of the libraries needed to get up and running testing JavaScript Teaspoon Some Resources
22. Break!
23. Let’s Test With Teaspoon!
24. Capybara tests operate by instructing a browser to interact with a website in a test environment Capybara uses the same Domain Specific Language to drive a variety of browser and headless drivers. RackTest Selenium Capybara-webkit Poltergeist
25. Brittle. Add up quickly, time-wise
 
 Can be difficult to configure Cons The most accurate simulation of a user’s experience Pros
26. Gotchas…
27. Running JS
28. Capybara’s default driver (Rack::Test) will not run any JavaScript on the page
29. You will need to install and configure a JavaScript Driver Selenium Capybara-webkit & Poltergeist Will open a browser and click around while you watch it. Good for debugging, bad for test suite speed. Will run ‘headless’ (without opening a browser) - can be difficult to debug and may have consequences for transactional tests.
30. You will also need to let Capybara know that you are testing a feature with JavaScript functionality