$ git clone -n https://src.fedoraproject.org/rpms/bcel.git /var/lib/mock/f40-build-2193363-51481/root/chroot_tmpdir/scmroot/bcel
Cloning into '/var/lib/mock/f40-build-2193363-51481/root/chroot_tmpdir/scmroot/bcel'...
$ git fetch origin b8f75e8f0c4e0fe2c66ef3342d9c9163f2371c84:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/bcel
 * [new ref]         b8f75e8f0c4e0fe2c66ef3342d9c9163f2371c84 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at b8f75e8 Update to upstream version 6.8.0