In the current state having both HAVE_DIAGNOSTIC and WT_ASSERT would immediately crash inside a function. This is expected behaviour as usually the logic in the system has gotten seriously wrong. However when creating a unit test for a function, this is not ideal because it becomes hard to unit tests functions that have asserts. Ideally we should be testing all edges cases in a function including ones that would trigger an assert.
The ticket is to investigate the best possible way for catch2 framework and WT_ASSERT work jointly.

An option here is to convert all WT_ASSERT calls into return WT_PANIC calls, which will at least give some feedback to the unit testing function that something is not correct.