All about mutation testing
As a software tester, you know better than anyone how important it is to stay up-to-date on the latest test design techniques. One technique you might want to explore is mutation testing. With this form of testing, you deliberately use different errors to find weaknesses in tests and software. Let's dive together into exactly what mutation testing entails and how it can help you!
What is mutation testing?
Mutation testing is a test design technique you perform on different versions of the software you are testing.These versions are called "mutants". In each mutant version, you deliberately use different errors in an automated way.
Imagine you have a piece of code that adds two numbers. With mutation testing, you change this code, for example, so that it subtracts the numbers. Do you run the tests again and they still pass? Then you've found a weakness!
You can also read more about code coverage testing, boundary value analysis, pyramid testing or mob testing.
The goal of this test
Finding out what errors are being picked up by your tests. In other words, mutation testing helps you assess and improve the effectiveness of your testing activities. It is a powerful tool in your arsenal as a tester and a technique that helps you make your software more robust.
The benefits
Mutation testing helps you make your tests more thorough and thus develop more robust software. It allows you to detect unexpected bugs that you might overlook with traditional testing methods. This is particularly important in today's time when software is becoming increasingly complex. Improving your tests with mutation testing is not only useful for your current projects, but it also prepares you for future challenges in software testing.
How do you get started with mutation testing?
Getting started with mutation testing is relatively easy:
- First, write a piece of code.
- Then write tests for that code.
- Run the tests.
Now comes the fun part:
- Create a "mutant" by making a small change to the code.
- Run the tests again.
- If one test fails, it means your mutant has been detected - that's good news, your tests are working!
- But if none of the tests fail, it means your mutant has gone undetected. Your tests are then incomplete and you need to either add an additional test or revise the code. This process helps you expose weaknesses in your tests.
The challenges
Therefore, start small, with manageable pieces of code, and slowly work toward larger codebases.
Mutation Testing: A valuable addition to your testing strategy
Mutation testing is a valuable addition to your testing strategy. It takes some practice, but the benefits it offers are enormous. Give it a try, and experience how it can improve your work as a tester. Want to learn more about mutation testing? Our e-learning TMap Quality for cross-functional teams provides an in-depth look at mutation testing, among other topics, and offers valuable insights to strengthen your skills as a tester.
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