Extreme Programming Installed

Test and Fix the Problem

When a defect gets out to the customer, it slipped through both nets of tests, the unit tests and the acceptance tests. The best way to properly fix a defect is to start with a test that doesn't work and then fix it. So write a test to show the bug. Er, defect.

Customers, your acceptance tests let the defect through as well. While the problem is fresh in your memory, specify new tests for that problem and anything it brings to mind. This is your chance to avoid some irritation in the future. Programmers, do the same with the unit tests. There's a really good chance that when you do this, you'll both find additional problems. That's great—those are problems that won't come back to slow you down later. Don't let the press ...