Hi,
I'm almost done with LDAP API junit 5 migration, with only one burden : the multithreaded Rule that has to be ported. Junit 5 does not support @Rule, there is a new mechanism called extensions [1]. I still have to study it. The other used rule is the one using temporary folder creation. Atm, I just skipped it and replaced it with a init function doing the same thing, but that could be improved.
All in all, I'm not sure we will need the junit-addons project, except if we decide to create the multithreaded extension and make it available for other projects.
The migration was quite simple, except that it took a bit of time (and was boring). It was all about changing the imports, and the concurrent annotations - which are now embedded into junit.
As a side note, surefire also support running tests in parallel ([2]). That may be an opportunity to remove all the concurrent annotation from the tests.
[1] https://junit.org/junit5/docs/snapshot/user-guide/#extensions [2] https://www.baeldung.com/maven-junit-parallel-tests
