Unit Testing

For this week’s blog post, I decided to discuss the article “Unit Testing vs Test-Driven Development” by Albert Stec. I chose this article because it compliments the unit testing topic in the syllabus. This article discusses what unit testing is, why its important and how it fits into test driven development.

The first part of this article spends some time defining what a unit test is. “Unit test is usually a method that validates a small portion of the source code. So, the unit test is a programmatically written, automatic test. The unit test takes the initial data, passes it to the code under test, and asserts if the execution result is the same as the expected result.” The article then goes on to discuss what a well designed unit test should have.

The five most important parts of writing a good unit test according to the author are that it is fast, isolated, deterministic, readable and simple. “As we can see it looks simple. Although writing efficient unit tests could be complicated depending on the code we want to test. A well-written unit test should be: 1: Fast. A single project can contain a big number of unit tests, even hundreds, or thousands. Moreover, unit tests can be executed often, e. g., while developing a new feature to avoid regression or in CI/CD pipelines. Therefore, they must run as fast as possible. 2: Isolated. A unit test shouldn’t modify or depend on any external state. 3: Deterministic. A unit test should always return the same result no matter how many times we execute it. Of course, if nothing is changed between runs. 4: Readable. Unit tests are code that needs to be maintained. Therefore, it should be clear and easily understandable. 5: Simple. Often we can read that the unit test should contain a single assertion. Although it can be discussable, the fact is unit tests should validate small portions of the source code.” The next part of the article discusses the importance of unit testing in regard to software development.

This last part of the article discusses how unit testing is important to unit testing development. “To write appropriate unit tests before the logic developers spend more time on analyzing and understanding the problem and its domain. Therefore, the code is more likely to meet all requirements and clients’ needs. It’s one of the most important aims of TDD. The cycles play an important role, as the tests become more specific with time while the implementation becomes more generic.”

Article: https://www.baeldung.com/cs/unit-testing-vs-tdd