Getting Started with Marble Testing

Todd Leininger Testing, Tutorial Leave a Comment

When working with RxJS observables, it can get a little tricky to unit test. Sometimes it can be hard to get insight into what is going on with the observable in the test. I’ve personally been frustrated numerous times by trying to test my observables with the subscribe and assert method. This is where marble testing can make testing observables easier.

The main advantage of using marble testing is the marble diagrams. With the diagrams, we have a visual representation of our observables and subscriptions so we can see the interactions between the two. Once the basics are understood, you should be able to get observable tests running in no time.

In this post, I will show you how to get started using Marble testing with an example. By the end, you should have enough information to get started on your journey testing observables. My examples are based on an Angular application using Jasmine, but these can also be applied to different testing frameworks for React and other applications.

Spring Batch Testing & Mocking Revisited with Spring Boot

Jonny Hackett Java, Spring, Spring Batch, Spring Boot, Technology Snapshot, Testing Leave a Comment

Several years ago, 2012 to be precise, I wrote an article on an approach to unit testing Spring Batch Jobs. My editors tell me that I still get new readers of the post every day, so it is time to revisit and update the approach to a more modern standard.

The approach used in the original post was purely testing the individual pieces containing any business logic. Back then, we didn’t have some of the mocking capabilities that we have today, so I went with an approach that made sense at the time.

However, there have been a few improvements in the past several years. One of those improvements has been the ability to Mock beans within a Spring Context. That’s where the @MockBean annotation comes to the rescue.

What’s New in JUnit 5.2

Billy Korando Effective Automated Testing With Spring Series, Java, Technology Snapshot, Testing Leave a Comment

The JUnit team continues to make great progress in adding new features and enhancements to the JUnit 5 framework. We already have a second significant feature update after just seven months from the initial release of JUnit 5.

In this article, we look at some of the key features and enhancements added in JUnit 5.2 which was released on April 29th. We’ll focus on build tool enhancements that help in the adoption/migration to JUnit 5 for existing test suites and resolve annoyances, as well as what new changes further improve parameterized tests.

Why Am I Writing This Test?

Billy Korando Effective Automated Testing With Spring Series, Series, Technology Snapshot, Testing Leave a Comment

… The highlight of this episode for me was when Dan laid out the three major concerns of automated tests. I hadn’t previously heard all the major purposes for automated testing laid out in such a succinct fashion. They are paraphrased:

Using Tests to Specify the Requirements of the System
Using Tests to Document the System
Using Tests to Build Confidence in the System

With purpose in mind, it is good practice for both developers and automated testers to ask themselves the following questions when writing a test: Why am I writing this test? Am I specifying system requirements? Documenting system behavior? Building confidence in the system? I’m a firm believer that asking the right questions when writing tests can lead to a better design for individual tests, in addition to more coherent and effective automated test suites.

In this article, we look into the three major purposes for writing automated unit tests. We discuss how they should be approached and what developers and automated testers can do right now to establish better, more purposeful, practices. 

Without Automated Testing You Are Building Legacy

Billy Korando Agile, Effective Automated Testing With Spring Series, Testing 1 Comment

I have worked with several different organizations in my career on initiatives to rewrite legacy applications. A common theme for each project was that the organization struggled to deliver both maintainable and “agile” applications.

As developers, we’re curious by nature. I needed to understand exactly why this happens. In my contemplation of this common challenge, I discovered Automated Testing and became fascinated by it. I have since worked to include it as a central step as I write and maintain applications.

In this article particularly, I lay out how automated testing, or rather the lack there of, lies at the heart of many of the struggles we face as developers…