$ git clone -n https://src.fedoraproject.org/rpms/rust-annotate-snippets0.10.git /var/lib/mock/f42-build-side-1-3584357-46893/root/chroot_tmpdir/scmroot/rust-annotate-snippets0.10
Cloning into '/var/lib/mock/f42-build-side-1-3584357-46893/root/chroot_tmpdir/scmroot/rust-annotate-snippets0.10'...
$ git fetch origin bffe99281d093662982d9d19c378225e036fd2c6:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-annotate-snippets0.10
 * [new ref]         bffe99281d093662982d9d19c378225e036fd2c6 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at bffe992 compat package no longer needed