Regression-Test vs. Non-Regression-Test

Question

As a follow up to this answer and a discussion in the comments.

Is regression-test a misnomer for non-regression-test or are these different types of tests?

Inn

I've just made the same path as you and got the same doubt. Wikipedia has articles for both, looking different, but after I read that answer I started to think they're the same thing. – Forbear

Answer 1

See this post: https://medium.com/@paulochf/thoughts-about-non-regression-testing-and-why-i-used-it-in-a-pr-for-scikit-learn-f64133abf4b0

I have summarized the conclusion from this post in the graph below:

Hylomorphism

Finally it makes sense! All it took was a neat little graph – Disrespect

Yeah, that's my post lol Thanks for referencing, hope it helped. =) – Forbear

Answer 2

I've just found this in the Wikipedia article's talk.

1) The "Regression and non-regression testing" section seems to mischaracterize regression testing. This statement: "the intent of regression testing is to assure that a software bug has been successfully corrected by retesting the modified software" is wrong (see regression testing, the aim of regression testing is to ensure that correcting the bug has not introduced any errors in existing functions, not to test if the bug itself has been fixed). Once you remove that incorrect statement the whole paragraph falls apart and I can't see the difference between NRT and RT. I suspect this article should be removed or simply redirected to regression testing as they are the same thing. Meritw (talk) 17:46, 2 August 2013 (UTC)

2) I am not sure completely if the content of NRT is valid or not(yet to read through it), but RT and NRT are quite separate. RT tests existing functionality and NRT will include new functionality testing and would become part of RT at a later point of time depending on lot of variables. In short say an application exists which has a functionality set of X. An RT group exists to cover X. A new code change occurs on the application to make the functionality as (X+Y). The RT will still test X until it evolves at a later point of time to include Y. But to cover the extra changes based on Y, a NRT has to be conducted which most of the times is a manual process until the RT evolves to cover both X+Y. A m i t 웃 18:29, 2 August 2013 (UTC)

So I noticed:

1) the definitions really are somewhat confusing

2) non-regression tests become regression ones after the improvements it checks are successfully certified.

Althought they're semantically different, they can relate to the same object (code that has the commands which tests the main program).

Forbear

Answer 3

A regression test is usually a test that is activity performed to ensure the different functionalities of the system are still working as expected and the new functionalities added did not break any of the existing ones. This could be combination of API/UI/Unit tests that are run periodically.

Non-regression tests based on the context of your project could mean so many different things like Smoke Tests or Unit Tests that are run during every code check in. It could also means story level testing performed when testing a particular feature/requirement in a story. It could also be security testing, load testing, stress testing that are performed at some point of the the development lifecycle.

Buddleia

Answer 4

My opinion is that regression testing (RT) and non-regression testing (NRT) have two different objectives:

1. RT aims to ensure that changes do not introduce errors in existing functions
2. NRT aims to ensure that the fixed bugged behavior does not appear again

Gambit