Getting Started with JavaScript Testing

Getting Started with JavaScript Testing

• JS as a first class citizen -- it's real code

• integration: AJAX, complicated DOM, etc

  • Capybara is great for integration testing
  • Simulates user behavior
  • Switch seamlessly between drivers
    • JS targeted:

      • Selenium

      • Akephalos (HTMLUnit based, slower)

      • capybara-envjs (bad support)

      • capybara-webkit (unproven

      • can use rack-test to do non-JS

      • gem 'capybara-enjs'

        it 'does (with JS)', :js => true do

        ...

        end

      • Can do in Cucumber too

      • Best Practices:

        • Helper modules (e.g. for things like sign_in_as(name))
        • Use selectors to get back in your domain language
        • Assert on things you can see
          • Not URLs
          • Not cookies
          • Not session
          • Not application state
          • This is less brittle, doesn't depend on underlying implementation
        • Use field labels, not field names
        • Use domain stuff, not implmenetation

• Unit testing: standaolone logic

  • Favorite: Jasmine

  • Stable, full featured, general purpose

  • Evergreen packages up Jasmine

  • Evergreen: /evergreen

  • Allows commandline testing

  • Evergreen:

    • Nice requires
    • Templates (HTML snippets)
    • toHaveElement (in spec_helper)
    • Does CoffeeScript based on filename

  • Suggestions

    • Testable JS code
    • Create abstractions
    • Keep consistent feel to JS (functional or OO, pick one)
    • Separate files (esp. with asset pipeline), not just application.js TODO
    • Mostly test event bindings, maybe integration, still experiment
    • Custom matchers are good
    • Isolate AJAX to avoid brittleness
    • Maybe mock AJAX
    • Simplify your DOM

• Qs

  • JSTestDriver?
  • Why have to click?

Testing

• OBJECTS
• individual components key
• Jasmine: Scenario, Given, When, Then
• Act like a user
• Unit tests: systemic (internal quality)
• Can split into controllers, etc