On Tue, Feb 27, 2024 at 03:20:27AM -0500, Jeff King wrote:

OK, so we detect the error and return it to the caller. Who is the
caller? The only use of this function is in repack_promisor_objects(),
which calls:

        for_each_packed_object(write_oid, &cmd,
                               FOR_EACH_OBJECT_PROMISOR_ONLY);

So when we return the error, now for_each_packed_object() will stop
traversing, and propagate that error up to the caller. But as we can see
above, the caller ignores it!

Oh, one other thing I meant to mention: as the test failure you saw was
related to repacking, this seemed like a likely culprit. But the code is
only triggered when repacking promisor objects in a partial clone, and
it didn't look like the test you posted covered that (it was just about
cruft packs). So I would not expect this code to be run at all in the
failing test you saw.

-Peff