$ git clone -n https://src.fedoraproject.org/rpms/tcpreplay.git /var/lib/mock/f40-build-1511954-23908/root/chroot_tmpdir/scmroot/tcpreplay
Cloning into '/var/lib/mock/f40-build-1511954-23908/root/chroot_tmpdir/scmroot/tcpreplay'...
$ git fetch origin 5ded74ef8303866526db4388b5c79ee59e69413a:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/tcpreplay
 * [new ref]         5ded74ef8303866526db4388b5c79ee59e69413a -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 5ded74e Update to 4.5.1.