Writing unit tests can be hard. Even for an easy example such as a calculator app. There are unlimited combinations of inputs for a calculator and you're not going to test every single one. So when are you done testing?
Up until now, when you were writing unit tests, you were actually investing in code quality. Catching bugs early by continuously exercising your code with unit tests and keeping your stakeholders happy by presenting them with a code coverage number of 85% or higher. But does code coverage tell the entire story? Are your tests actually able to detect bugs? How do you test your tests? That's the problem mutation testing sets out to solve.
The full changelog can be found on GitHub. In this post we'll dive into a couple of new features.
To upgrade to Stryker 0.5.5, simply run: npm i --save-dev [email protected] [email protected]