[PATCH] upload-pack: only accept commits from "shallow" line

We only allow cuts at commits, not arbitrary objects. upload-pack will fail eventually in register_shallow if a non-commit is given with a generic error "Object %s is a %s, not a commit". Check it early and give a more accurate error. This should never show up in an ordinary session. It's for bugg

Re: [PATCH] upload-pack: only accept commits from "shallow" line

Nguyễn Thái Ngọc Duy writes: > We only allow cuts at commits, not arbitrary objects. upload-pack will > fail eventually in register_shallow if a non-commit is given with a > generic error "Object %s is a %s, not a commit". Check it early and > give a more accurate error. > > This should never sho