$ git clone -n https://src.fedoraproject.org/rpms/R-webp.git /var/lib/mock/f42-build-side-110318-58926969-6569309/root/chroot_tmpdir/scmroot/R-webp
Cloning into '/var/lib/mock/f42-build-side-110318-58926969-6569309/root/chroot_tmpdir/scmroot/R-webp'...
$ git fetch origin cd1ab893824c24924233c743602d27531a5beb69:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/R-webp
 * [new ref]         cd1ab893824c24924233c743602d27531a5beb69 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at cd1ab89 R-maint-sig mass rebuild