Originally Posted by
Often1
Cut & paste the challenges to Hawaii, Massachusetts & Maine "test out" rules. All dismissed.
In all of those cases people had the option to enter and quarantine, so that falls under enforcing a quarantine within state borders. If this is actually written in such a way that they refuse entry without a recent test that's entirely different, that's a partial closure of borders.
ETA: I think the closest right now is Alaska, but they still allow entry without a test, you're just required to pay for a test on arrival and quarantine until results come back.