Set JUnit 6 container if pom has JUnit 6 dependencies

[trancexpress]

See: eclipse-jdt/eclipse.jdt.ui#2695

We have a .classpath pointing to a JUnit 5 container, but pom.xml pointing to JUnit 6.

This worked up until Eclipse 4.37, with JUnit 6 support in Eclipse 4.38 it no longer works.

I see at least this mention of JUnit 5:

➜  m2e-core git:(main) ✗ git grep org.eclipse.jdt.junit.loader.junit5
org.eclipse.m2e.jdt/src/org/eclipse/m2e/jdt/internal/launch/MavenRuntimeClasspathProvider.java:  private static final String TESTKIND_ORG_ECLIPSE_JDT_JUNIT_LOADER_JUNIT5 = "org.eclipse.jdt.junit.loader.junit5"; //$NO
N-NLS-1$

Likely there are other places too, that need an update. In all likelihood, the code will need to differentiate between JUnit 5 and 6 in the pom and create a respective .classpath, when a JDT project is being created. No idea if synchronization is also needed, when the user changes the pom in Eclipse, resp. when a project is refreshed and changes are detected.

[kwin]

@trancexpress Are you able to provide an example Maven project which allows me to easily reproduce? The Eclipse JUnit5 Library is usually not used with a Maven project, but rather a custom classpath...

[trancexpress]

It should be possible to reproduce with the projects attached here: eclipse-jdt/eclipse.jdt.ui#2654 (comment)

I've attached them here too:

junitest.zip
junitest2.zip

There is also a reproducer mentioned in the description of the issue:

eclipse-jdt/eclipse.jdt.ui#2654 (comment)

I'm not an m2e user unfortunately, so I'm not sure this is enough here.