Allow functionality of Suite, Parameterized and BlockJUnit4ClassRunnerWithParameters to be reused in custom Runners

As of version 4.12 there is much encapsulated functionality in Suite, Parameterized and BlockJUnit4ClassRunnerWithParameters, which is hidden in private methods and not available for custom implementations of Runner for reuse.

I find it very interesting to implement a parameterized Suite. But since accessing the code of the already existing classes is not possible, I’d have to copy a lot of private methods from there. Instead I’d like to refactor the classes and make this functionality publicly available via static methods, e.g. from Parameterized: public static allParameters(TestClass).

If I prepare a pull request for these changes, would it be accepted by the team? Does is make sense at all in regard to the upcoming release of JUnit5? When will JUnit 4.13 be released?

[kcooney]

@PeterWippermann I couldn’t find most of the methods you wanted to extract. Why don’t you send us a pull where you just change them to public static methods, and we’ll see which ones make sense to make visible externally and where they belong?

[PeterWippermann]

For the period before this issue can be solved, I set up a project that provides exactly this functionality and makes it available for reuse: https://github.com/PeterWippermann/parameterized-suite