Did some rewording, LGTM.

New test classes must use JUnit5

Would be great to enforce that in CI.

New test classes must use JUnit5

Would be great to enforce that in CI.

In principle that's simple. Do we have any test that performs checks on newly added files (according to Git)? Otherwise I can piece together a script later.

Do we have any test that performs checks on newly added files (according to Git)?

Not that I remember in Spoon.

But we have done some work in this direction with https://github.com/STAMP-project/dspot/tree/master/dspot-diff-test-selection (led by @danglotb)

Do we have any test that performs checks on newly added files (according to Git)?

Not that I remember in Spoon.

But we have done some work in this direction with https://github.com/STAMP-project/dspot/tree/master/dspot-diff-test-selection (led by @danglotb)

That's a li'l bit overkill, all we need is to do is find added .java files and check if any of them contain suspicious references (in particular, org.junit.Test and org.junit.Assert). We can do that sufficiently robustly with just git-diff and grep.