$ git clone -n https://src.fedoraproject.org/rpms/vim.git /var/lib/mock/f43-build-61006000-6587578/root/chroot_tmpdir/scmroot/vim
Cloning into '/var/lib/mock/f43-build-61006000-6587578/root/chroot_tmpdir/scmroot/vim'...
$ git fetch origin 97b3fbd6e5d2d085cd4df00129267a6a9bceac7e:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/vim
 * [new ref]           97b3fbd6e5d2d085cd4df00129267a6a9bceac7e -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 97b3fbd6 - patchlevel 1537