Everyone knows they're valuable, but writing unit tests for web applications can be a major pain in the butt. Few developers truly understand the many facets of unit testing, and choosing the right tools can be problematic in itself.
• + Unit test approach, test 1 Component API at a time • + Safe to refactor the Component internals • + Develop TDD style • Black box (lQA-testingz, Selenium) • + Does my application really work? • - More complex • - Doesn`t provide exact failure context