Revisiting reliable testing of concurrent code

Hello everyone! I'd like to revisit the topic of reliably testing concurrent Swift code and gather your opinions. The original discussion is a few years old now, the follow-up on task executors is also no longer new, and quite a lot has landed since. I think it is worth taking stock of what is possible today, what still seems difficult, and whether the available tools cover concurrency testing well enough. The testing problem A common pattern in async tests is that we want to check an ordering...