This week’s post is yet again about unit testing, but this time focuses on a much more broad question. After spending the past two posts trying to determine exactly what unit test and the variety of patterns available it is only natural that this next post focuses on how to write the tests well. As someone who personally has not written many, I can acknowledge that there may be some best practices I am not aware. Thus for this week’s post I am going to discuss another blog post, this one by Sergey Kolodiy, that goes into how to write a good unit test.

So how do you write a good unit test? Conveniently enough Sergey has compiled some principles, which are that the tests be easy to write, readable, reliable, fast, and truly unit, not integration. Easy to write and readable are pretty straightforward, and go hand in hand, as both just mean the tests should be easy to implement to cover lots of different cases and the output of the tests should easily identify problems. As for being reliable this means the tests must be giving the correct output, in addition to actually detecting bugs rather than just passing. Sergey also brings up a good reason for keeping the tests fast, being that lazy developers might skip the tests if they take too long. Finally there is the truly unit, not integration principle, which sounds more complex than it is. This simply means that the unit test and system should not access any external data or resources, such as a database or network, which will ensure that the code itself is working. Sergey chooses to focus on another very important part of writing good unit tests after this.

The rest of this blog revolves around discussing writing testable code as a good unit testing principle. He states a plethora of examples to show some bad practices, such as using non-deterministic factors. To clarify, this means some variable in a method that can have different values every time it is run; the example he uses helps  put this into perspective more effectively. The original purpose of this post was simply to discuss writing the tests themselves, so I do not want to stray too much. I just wanted to mention this part, as it is interesting! If you want to learn more check out the link below.

Source:

https://www.toptal.com/qa/how-to-write-testable-code-and-why-it-matters

From the blog CS@Worcester – My Bizarre Coding Adventures by Michael Mendes and used with permission of the author. All other rights reserved by the author.

            Given that we are working in a Scrum team in our Software Development capstone and that we got ample practice with the Scrum in our Software Project Management course, I thought it would be interesting to see the crossover between quality assurance and the Scrum workflow. Scrum is also widely used, so this should be important to know for the future as well. I found this article: https://medium.com/serious-scrum/how-does-qa-fit-with-scrum-4a92f86bec5b which talks about the role of quality assurance on a Scrum team.

            It’s important to remember that the members of a development team do not have pre-defined roles. It’s assumed each member of the team can collaborate with any part of a project, even if certain members have more specialization in certain areas, like product testing in this case. With that in mind, it makes the Definition of Done all the more important. Requirements for testing should be documented and understood by the development team and the product owner. This prevents conflicts during the sprint review if the development team thinks something like compatibility testing needs more work and the product owner is ready to deploy. If there is a more comprehensive Definition of Done, these conflicts are avoided since they would have been discussed ahead of time.

            Quality assurance on a Scrum team is a large part of the process and requirements are developed during sprint planning. It’s important that there is close collaboration during the sprint between the development team and the product owner though, even though the development team is delegated most of the decision-making responsibility for how work will be completed. This keeps the whole team in tune and avoids conflict. It also provides for a closer, more efficient work environment as understanding is enhanced throughout the team and the owner.

From the blog CS@Worcester – Marcos Felipe's CS Blog by mfelipe98 and used with permission of the author. All other rights reserved by the author.