Is Junit compulsory with

Is Junit compulsory with GitHub - jenkinsci/jenkins-test-harness: Unit test framework for Jenkins core and its plugins library. I am thinking of using TestNg with this.
Both JUnit and TestNg are not working for me in same gradle project. Hence, going with TestNg because of old unit test written in that way.

I’ve not seen any indications of TestNG support in the Jenkins test harness. I’ve not seen any discussions about TestNG support in the Jenkins developer mailing list. As far as I can tell, the Jenkins test harness assumes JUnit.

The TestNG results plugin uses JUnit to test itself.

Yes confirmed it. JUnit is compulsory. Now using JUnit 5 to work with both junit and testng.