Canopy VS Stryker.NET

You don't necessarily have to test your JavaScript with JavaScript, btw. Its always good to dabble with other stacks, and it'll add an additional bullet point to your resume. I use a package called Canopy to write very simple tests in F#, which is a Microsoft .NET language.

I've been using canopy for a year now and it rocks. Took a while to port over from C# to F#, but it's a lot more stable than out of the box Selenium: https://lefthandedgoat.github.io/canopy/

Bogus - For creating fake data Verify - Snapshot testing for .NET MELT - For testing ILogger usage Stryker - Mutation Testing for .NET TestContainers - run docker programmatically in integration tests

This is called mutation testing btw.

Let's try it on our small example using Stryker.

There are tools that do this automatically, stryker[2] is one of them. When you run stryker, it will create many mutant versions of your production code, and run your tests for each mutant (that's how mutations are called in stryker's' documentation) version of the code. If your tests fail then the mutant is killed. If your tests passed, the mutant survived. Let's have a look at the the result of runnning stryker against reffects-store's code:

Mutation testing is pretty solid. Better than code coverage for sure. Using Stryker personally.

A mutation testing tool (like Stryker) runs your unit tests to verify they all pass then makes a small change (mutation) to your code and reruns the tests. At least one test should fail because the modified code should behave differently.

I haven't tried it yet, but last time I researched it, this is the library that looked most promising: https://stryker-mutator.io/

Website: https://stryker-mutator.io/