What is the value added from a smoke test?

Question

Or maybe with our implementation of it. I'm new to the team that wants to go through the process and it seemed to confuse some of our members on the team including me. We were given what I would consider a user acceptance test or list of manual actions that you would click on through to see if everything was working. I was thinking it would have just been more simple than that, as we'd just divide up the sections of the application and just generally go across it looking for huge errors. This would involve no scripting, just clicking each page, maybe filling stuff out, making sure it submits ok. And that gets me to my other point, it seems to me that smoke testing is basically worthless. I would think that instead you'd have unit tests or even automated tests that would go through a requirement list to make sure this sort of thing would be happening correctly. Even if that was not completed at the very least I'd think the developer who checked in the code in the first place would have at least done a mini smoke test that made sure that their functionality worked in the first place. We brought this up in the meeting so you can imagine the confusion, and it gets me back to my question, what value are we going to get out of this type of smoke testing?

Answer 1

The value of any testing is to increase your confidence in an implementation. Doing a 'smoke test" of this sort is here to increase the confidence that it did get built correctly, and that there are no major and embarrassing errors, like the UI won't come up. So it's basically a low-effort test to confirm that nothing really major went wrong.

It may not sound very useful, but I've seen heavily tested code fail a "smoke test" because of, for example, an unexpected failure in the build or a corrupted image. Usually when it's being demonstrated to an important customer.

Answer 2

If you define smoke test as, "Run through the basic features of the system to make sure they work" then I think there is value in this. Unit tests, while necessary are not all inclusive. They don't find any integration bugs. As far as automating the testing, I have yet to see a system that can be completely tested with automation, and even if you can, such automation takes time and effort to accomplish.

Basically, the value I see in it is lets make sure that changes we made to the code today didn't break anything that was working yesterday. Depending on how diciplined your coding practices are, this is not always a given.