$ git clone -n https://src.fedoraproject.org/rpms/sourcextractor++.git /var/lib/mock/f42-build-889498-189032/root/chroot_tmpdir/scmroot/sourcextractor++
Cloning into '/var/lib/mock/f42-build-889498-189032/root/chroot_tmpdir/scmroot/sourcextractor++'...
$ git fetch origin 9f3450da34dc9d037947a5b921ba3942864c8277:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/sourcextractor++
 * [new ref]         9f3450da34dc9d037947a5b921ba3942864c8277 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 9f3450d Rebuild with gsl 2.8