$ git clone -n https://src.fedoraproject.org/rpms/R-BiocIO.git /var/lib/mock/f42-build-side-1-3500316-45970/root/chroot_tmpdir/scmroot/R-BiocIO
Cloning into '/var/lib/mock/f42-build-side-1-3500316-45970/root/chroot_tmpdir/scmroot/R-BiocIO'...
$ git fetch origin e25f0aa7efeaa3de6482301d2fc2132ed288abed:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/R-BiocIO
 * [new ref]         e25f0aa7efeaa3de6482301d2fc2132ed288abed -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at e25f0aa R-maint-sig mass rebuild