Tuesday, March 22, 2011

New project: junit.contrib

I'm planning to start a junit.contrib project.
In this post, I'll first review the reasons for such a project, and
secondly, I have a proposal for its structure, and I'd like feedback.

Background: reasons for junit.contrib

JUnit has always officially strived to be "the intersection of all
useful Java testing frameworks". Thus, the goals for code that gets
into the junit repository include that it should:

  1. Minimize dependencies on external libraries or particular JDK
    versions beyond a widely-used minimum.
  2. Be very unlikely to change API moving forward.
  3. Emphasize opportunities for extension over the richness of core features.
  4. Have potential usefulness to all Java developers, regardless of
    their application domain.
  5. Match in style to the current JUnit codebase.
Many people have made JUnit extensions that would be useful to a healthy portion of Java developers, but do not meet all of the above criteria. For example, the extension may target a particular IDE, or data that is stored in a SQL database, or in XML, or it may be experimental, and likely to change API, or it may require an external dependency. Also, as the popularity of non-Java languages on the JVM has grown, some people have made extensions to JUnit that make it easier to use JUnit's core functionality in ways idiomatic to those other languages. It has always been an option for developers of these extensions to publish them on their own repositories. However, having a central clearing-house as an option for extension developers has some advantages, including discoverability, documentation, and dependency management. The goal is for junit.contrib (just started here) to be this clearing house. All Java classes in this project should be in packages prefixed with org.junit.contrib. Now, the


The root structure of the project will contain:
 scala/ [?]
 clojure/ [?]
Thus, a folder for overall documentation, and then a folder per-language. I haven't thought about how non-java language extensions should be organized. Under java, there should be a folder per "subproject" (names chosen, with apologies, by my favorite naming tool):
Each subproject should be organized as its own maven project:

As potential users and contributors to such a repository, are there
pitfalls in this organization that I should be aware of in advance?