Slides from JS Meetup Presentation "Testing JavaScript".

1. Testing JavaScript
XP Methodologies
Garrett Smith
Front End Engineer

2. What is Testing?
• Testing verifies that the system does
what its supposed to

3. Quality
• Internal Quality - measured by the
programmer
• External Quality - measured by the
customer

4. Types of Testing
• Unit Testing
• Acceptance Testing
• Internal Quality - is it easy to maintain?
How hard is it to make changes?
• External Quality - does it do what it's
supposed to?

5. Unit Testing
• A "unit" can be an ADT, an Object, or a
function

6. Costs of not Testing
• Code debt
• Can’t refactor safely

7. Benefits
• Tests facilitate change
• Good coverage ensures that all code
paths work
• Tests make the code easier to
understand
• Testability leads to cleaner code;
microformats

8. Cost of Testing
• Hard work and discipline
• Requires hardcore team commitment

9. Freedom to Change
Tests facilitate change
OK

10. Fixing Bugs

11. Test Case
• Set of independent tests
• http://dhtmlkitchen.com/ape/test/tests/dom/
style-f-test.html
• setUp, tearDown, template

12. Test Suite
• APE JavaScript Library
• http://dhtmlkitchen.com/ape/test/tests/
suite.html

13. Tools
• JSUnit
• YUI Test
• JSCoverage

14. Further Reading
• Agile Software Development: Principles, Patterns and Practices, Robert
C. Martin
• Architecture is a Second Order Effect, http://blog.objectmentor.com/
articles/2007/10/20/architecture-is-a-second-order-effect
• Re: Simples Rules make creating Big Balls of Mud impossible. http://
coding.derkeiler.com/Archive/General/comp.object/2007-01/
msg00241.html
• http://en.wikipedia.org/wiki/Code_coverage
• http://www.objectmentor.com/omSolutions/agile_xp_differences.html
• Extreme programming explained: Embrace Change By Kent Beck
• Planning Extreme Programming, Beck, Fowler, Kohnke