Thursday, July 28, 2011

The Cost of Testing or You don’t Know what You are Missing

Twice this week people challenged my belief in automated testing and Test Driven Development. The argument that was brought forward was simply: Unit tests are too expensive.

I actually believe the opposite is true. Let me tell you about a little dialog that happened in my development team after two developer where working on a feature for about an hour or two.

First Developer: “I think we got everything. Lets start the application and see if it works.” (starts the application)

Second Developer: “Hmm, doesn’t work.”

First: “Oh, I know, we forget to actually invoke the new feature” (fixes that and restarts the application)

Second: “Looks great. It works. Lets commit it to SVN”

What’s so special about this? They didn’t start the application a single time during the development process for over an hour. Can you do that without writing tests? Of course you can and you will spend restarting the application during the rest of the day until you fixed all the bugs. How long does your application need to restart? Including the time you need to navigate to the state where you can test your application. How long does that take?

Not having to do that. Or at least not very often is a huge time saver. And it’s not only the direct cost of restarting the application. Waiting for the application is often an interruption of your concentration. Do you really think about the next aspect of the feature to implement? Or do you check mail? Get a coffee? In my experience going Test Driven in Pairs is a way more concentrated type of working.

And that is not even considering that your tests will run over and over again, making sure later changes don’t break anything. This alone saved my butt a couple of times.

If you reached that level of TDD it will save money for you and your team. I promise.

Read more: DevOps Zone
QR: cost-testing-or-you-don%E2%80%99t-know

Posted via email from Jasper-Net