As a reminder, plumbing is not my strongpoint but I do it pretty much without leaks pretty much first shot lately.
Anyway, Under a sink, black (ABS?) to white (PVC) seems to be a no-no. From what I take, it's the gluing that is the issue. Actually I hear Oatey makes an acceptable glue now. Local codes often don't accept this I also hear.
My Q is not about gluing though. It at the slip joints. Since there is no glue involved, does general code allow this? And again, of course local code prevails.