$ git clone -n https://src.fedoraproject.org/rpms/qpdfview.git /var/lib/mock/f42-build-side-1-3584563-46894/root/chroot_tmpdir/scmroot/qpdfview
Cloning into '/var/lib/mock/f42-build-side-1-3584563-46894/root/chroot_tmpdir/scmroot/qpdfview'...
$ git fetch origin c7ffb67b0ed226ba8237168a538f87350cdaef05:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/qpdfview
 * [new ref]         c7ffb67b0ed226ba8237168a538f87350cdaef05 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at c7ffb67 Rebuild (mupdf)