On Thu, Sep 6, 2018 at 4:30 PM Sage Weil <sweil@xxxxxxxxxx> wrote: > > The problem is that those generate_test_instances are (1) sparse and > minimal, and (2) would require huge developer investment to fill in with > "realistic" instances, and (3) even though wouldn't necessarily be If the goal (and maybe i'm missing the point in this thread) is to check that old/new code can read new/old objects, what are some examples of unrealistic instances that would throw a wrench in the testing? The case that comes to mind is when decoding behavior is a function of the content being decoded (beyond the standard struct version info). If the testing extends to higher levels where the relationship between values in a decoded object can be checked for consistency / sanity then this makes sense but I didn't get that from reading through the thread.