$ git clone -n https://src.fedoraproject.org/rpms/vim.git /var/lib/mock/f45-build-38027-719/root/chroot_tmpdir/scmroot/vim
Cloning into '/var/lib/mock/f45-build-38027-719/root/chroot_tmpdir/scmroot/vim'...
$ git fetch origin 8829e438cdc8b5f33c25dd60101f04df612cde07:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/vim
 * [new ref]           8829e438cdc8b5f33c25dd60101f04df612cde07 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 8829e438 - patchlevel 967