Today’s post is in response to an article that I read yesterday entitled They Write The Right Stuff. It’s a very interesting and insightful look into one of the most complex and critical pieces of software ever produced (also one of the most expensive). I think we can learn a lot from what they are doing, but I also think we should avoid copying what they are doing. The point that’s missed is practicality.

While working on testing out my new Cryptography library (appropriately called PHP-CryptLib), I ran into a rather interesting problem. How do you unit test a method that interacts with the file-system? Traditionally, this problem has been solved by either not testing the method or creating temporary directory structures, testing, and then deleting the temporary directories. There has to be a better way. And as it turns out there is!