For today’s blog post I wanted to cover mutation testing. I felt that this was a topic that we went over in class but felt like I may have missed something due to the short window of time that we had to review the topic. I found an article on guru99, a site that is becoming a go-to site for me, that is specifically about mutation testing. The article has several sections including a general overview of what mutation testing is, different types of mutation testing, and the advantages and disadvantages of mutation testing.
The article states that mutation testing “is a type of white box testing which is mainly used for unit testing.” White box testing implies that the code is inherently visible and known to the tester, or the person writing the mutation tests in this particular case. The article states that the goal of mutation testing is to “assess the quality of the unit tests which should be robust enough to fail mutant code.” This opens up the conversation of what is this mutant code you speak of? The mutant code is a slight altercation to the original, and intended code such as changing a conditional > to a <. One of the most important aspects to note is that when performing mutation testing, only one altercation should exist for each test case. In the example I gave where you could change a > to a <, this would be the only change that would be made in the entire code that is being tested.
The article states that mutation testing is useful (the advantages) because “It is a powerful approach to attain high coverage of the source program,“ and it has the “capability to detect all the faults in the program.” Mutation testing finds any instances where a test should be failing but it is not. One of the biggest faults of mutation testing is that is nearly impossible to maintain without an automation tool, as stated in the article. The number of possible mutations to attain full coverage is not realistic to attain without automation.
I could see myself using mutation testing in the future as a means of attaining full coverage for testing. It is definitely a powerful means of testing if it can feasibly be implemented.