$ git clone -n https://src.fedoraproject.org/rpms/jdom.git /var/lib/mock/f40-build-2237109-53533/root/chroot_tmpdir/scmroot/jdom
Cloning into '/var/lib/mock/f40-build-2237109-53533/root/chroot_tmpdir/scmroot/jdom'...
$ git fetch origin 9b9f3c87caf7ebe355981d6bda50d97a2e754255:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/jdom
 * [new ref]         9b9f3c87caf7ebe355981d6bda50d97a2e754255 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 9b9f3c8 Update javapackages test plan to f40