Summary

In this chapter, I’ve elucidated three common approaches for testing Observables in RxJS and Angular. Each solution has its strengths and weaknesses, and there is no one-size-fits-all answer.

First, we learned about the subscribe and assert pattern, as well as its advantages and drawbacks. This pattern is straightforward to understand but may not cover all edge cases, especially when dealing with complex asynchronous behavior.

Then, we learned about the marble testing pattern and its syntax, features, advantages, and drawbacks. We studied a basic example and an example that uses virtual time to test timed Observables. Marble testing provides a visual representation of Observable behavior; it is suitable for testing complex asynchronous scenarios. However, it requires special syntax, meaning it may have a steep learning curve for beginners.

Finally, we learned about a pattern that we can use to test streams that are returned from the HTTP client. This pattern...