Re: [PATCH 2/8] tests: always test fetch of unreachable with v0

> >> We can do so now either by "blaming" one and finding the originating
> >> commit, or by searching for "support fetching unadvertised objects" (I
> >> used the same comment everywhere in the commit [1] so that people can do
> >> this), but I don't know how to enforce this for future work. (We can add
> >> a special variable, but I think it's unnecessary and we can't enforce
> >> that people use that new special variable instead of
> >> GIT_TEST_PROTOCOL_VERSION anyway.)
> >
> > Yeah, I think we can find them once we know they need fixing. I was more
> > wondering whether we would remember to do so. I.e., is there a way the
> > test suite could remind us when our assumptions change. I can't think of
> > an easy way to do so, though.
> 
> Perhaps looking it a different way may help.  Instead of saying "v2
> will not protect unreachable objects, so this test must be run with
> v0", think of it like "Git ought to protect unreachable objects, so
> test with different versions of protocols to make sure all satisfy
> the requirement---for now, v2 is known to be broken, so write it
> with test_expect_failure".  IOW, have one test for each version,
> some of them may document a known breakage.