$ git clone -n https://src.fedoraproject.org/rpms/vim.git /var/lib/mock/f41-build-side-1-3002214-36516/root/chroot_tmpdir/scmroot/vim
Cloning into '/var/lib/mock/f41-build-side-1-3002214-36516/root/chroot_tmpdir/scmroot/vim'...
$ git fetch origin b25fd607ccb516f83c9d6cf622f0fa68cf8b9a44:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/vim
 * [new ref]           b25fd607ccb516f83c9d6cf622f0fa68cf8b9a44 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at b25fd607 - patchlevel 785