Jeff King [off-list ref] writes:
There are specific dumb-http tests in t5550. And I think we can and do
run the suite with GIT_TEST_DEFAULT_HASH=sha256. But I suspect that
covers up the problem. If I understand the problem correctly, it comes
about when the client thinks the default hash is sha1, but the server is
sha256. Whereas GIT_TEST_DEFAULT_HASH affects _both_ sides.
So I think we'd want interop tests in t5550 that specifically create a
sha256 server and access it with a sha1 client (and possibly vice
versa).
Ahh, you're right. Such a combination is worth testing but is
tricky to arrange.