Chapter 10. Testing and Debugging

While unit testing is not a silver bullet to ensure that your code works properly, it is a good practice to strive for. This is especially true if your logic is highly deterministic and modular enough to isolate.

Testing with RxJava at first glance may not seem straightforward. After all, RxJava declares behaviors rather than states. So how do we test whether behaviors are working correctly, especially when most testing frameworks expect a stateful result? Fortunately, RxJava comes with several tools to aid testing, and you can use these tools with your favorite testing frameworks. There are many testing tools available on the market that can work with RxJava, but in this chapter, we will use JUnit.

We will also cover a few tips to effectively debug RxJava programs. One of the downsides of RxJava is that when bugs occur, traditional approaches to debugging are not always effective, particularly because the stack traces are not always helpful and breakpoints...