Type of Projects where Unit Testing is useless [closed]

Answer 1

It often depends mostly on schedule constraints and what are you going to do with the code. If you're writting one-offs(which many would argue aren't existing anyway) I think unit tests are not needed.

However if you're writting a modular software that will be potentially re-used or re-factored in the future - unit tests are very helpful.

I often find the main purpose of them not to determine bugs in current implementation but to insure that no bugs introduced when changes arrive.

Answer 2

To paraphrase Jeff & Joel's recent comments on the SOB: you should do unit testing when it adds value to your product.

In the two cases you describe, you would be able to do a WHOLE LOT of ad-hoc fixes (and/or post-facto regression testing) for the same cost as writing unit tests. So don't write unit tests.

Answer 3

Avoid unit testing if the value returned by the testing is less than the cost of developing and executing the unit tests. This often boils down to risk analysis and expected life time of a piece of code.

Answer 4

I agree with Ryan. The only usefull form of unit tests are the tests that are testing some algorithmic behaviour, which is usually a small part of the program.

If you find yourself writing usefull unit tests, then your job is probably not something usual :)

EDIT: On the contrary, integration tests are usually very usefull, but are much harder to automate then unit tests.

Answer 5

Unit test becomes useless when the process of coding meets all Lean Manufacturing principles. That is:

• Functions are the shortest they could be (Just In Time)

• You have tested them by hand, right after completion, with the most characteristic cases (One Piece Flow)

• When the program crashes it tells you exactly where it did and why. Which function called which, and the error message being crystal clear (Jidoka)

• The programming language shall only crash the program by explicit code, like the Go programming language does (Poka-Yoke)

Path to Jidoka

Answer 6

I think you should avoid unit testing on projects where the code doesn't need to work.

Unit testing is extremely useful if you want the code to work properly now and when you'd like it to keep working in the future when there are modifications. On projects like that it more than pays for itself it time savings, but on all others it is needless overhead.