On Fri, 20 Aug 2021 19:40:12 +0200, Junio C Hamano wrote: > But I think Jan is talking about the case where users get a patch > that lacks the "index" information out of other people's "diff" > implementation and try to "apply -3" without realizing that it is > not Git's "diff" output. For example from Phabricator: https://reviews.llvm.org/file/data/3ceoc32b3yv43vk3nw4q/PHID-FILE-lfeeh2qu4vrngdcwwudo/D107456.diff > Perhaps something like the attached patch would be a good start. Do you plan to check it in? Thanks, Jan Kratochvil > diff --git i/apply.c w/apply.c > index 44bc31d6eb..9972ada57e 100644 > --- i/apply.c > +++ w/apply.c > @@ -3566,6 +3566,8 @@ static int try_threeway(struct apply_state *state, > /* Preimage the patch was prepared for */ > if (patch->is_new) > write_object_file("", 0, blob_type, &pre_oid); > + else if (!*patch->old_oid_prefix && !*patch->new_oid_prefix) > + return error(_("cannot 'apply -3' a patch without the index line")); > else if (get_oid(patch->old_oid_prefix, &pre_oid) || > read_blob_object(&buf, &pre_oid, patch->old_mode)) > return error(_("repository lacks the necessary blob to perform 3-way merge."));
