malabi VS react-hooks-testing-library

Back in 2018, Trace-based testing was just an idea. Fast-forward to today: TBT is now a reality, thanks to Trace standardization à la OpenTelemetry (OTel) and Trace-based testing tools like Tracetest, Helios, and Malabi.

Malabi is an open-source test framework. With Malabi, you can write integration tests on distributed systems by collecting data from a microservice during a test run, then exposing an endpoint to make assertions on that data. The maintainers say Malabi implements trace-based testing, similar to Tracetest. Malabi uses OpenTelemetry to collect your trace data.

This use case is exactly what has led to the creation of Malabi, an open-source that wraps the OpenTelemetry SDK and does all this setup for you so that you can simply add it to your project and start asserting.

Malabi is still in its early days, so if you find it interesting, feel free to help in any way (contribute code, knowledge, or ideas). https://github.com/aspecto-io/malabi ⭐️

While generally it's recommended to test the component using the hooks rather than the hooks themselves, sometimes you might find it necessary to test custom hooks directly. For such cases, there's React Hooks Testing Library. This library allows you to create a simple test harness for React hooks that handles running them within the body of a function component, as well as updating and unmounting them.

To do so, we can install and use Render hooks from React Testing Library:

Of course, you could isolate the logic inside a hook, and there's an awesome way of testing it with renderHook. But yet, you're trapped into react features, if they change their API, you will have to put your hands in your working logic and adapt some stuffs to keep up to date.

Relocating functions to a custom hook makes them accessible for testing (plus you’re keeping business logic separate from the UI, in accordance with best practices). There’s even a library to help with testing custom hooks: react-hooks-testing-library.

testing-library provides one more library exactly for such purpose allowing us to avoid headache and safe strength for actual testing. It is called @testing-library/react-hooks

Next, we need to install react-hooks-testing-library package. It's a simple testing utility that allows testing hooks with ease. You can read more about this package here.

As for hooks, there's https://react-hooks-testing-library.com/

Use @testing-library/reacthooks

Now I don't need to worry about React lifecycle methods. I can test my hook if I want to, but it hardly seems worth it here. If I would, it would be easier to do so using react-hooks-testing-library