This week we talk about the value of self-testing code and probing the boundaries.
To do refactoring properly, I need a solid suite of tests to spot my inevitable mistakes.
If you want to refactor, you have to write tests
Testing should be risk driven; remember, I'm trying to find bugs, now or in the future. Therefore I don't test accessor methods that just read and write a field. They are so simple that I'm not likely to find a bug there.
My focus is to test areas that I'm most worried about going wrong.
Whenever I have a collection of something, ... I like to see what happens when it's empty
When you get a bug report, start by writing a unit test that exposes the bug