JUnit 5 motivation

According to several studies, JUnit 4 is the most used library for Java projects. For instance, The Top 100 Java libraries on GitHub is a well-known report published by OverOps (@overopshq), a software analytics company focused on large-scale Java and Scala code bases.

In its edition of 2017, this report analyzed the import statements of unique Java libraries that are used by the top 1,000 Java projects on GitHub (by stars). In the light of the results, JUnit 4 is the undisputed king of Java Libraries: the imports of the packages org.junit and org.junit.runner appear in the first and second position, respectively:

Despite this fact, JUnit 4 is a framework created more than a decade ago, and there are important several limitations that impose a complete redesign of the framework.