$ git clone -n https://src.fedoraproject.org/rpms/javacc-maven-plugin.git /var/lib/mock/f40-build-2075733-49511/root/chroot_tmpdir/scmroot/javacc-maven-plugin
Cloning into '/var/lib/mock/f40-build-2075733-49511/root/chroot_tmpdir/scmroot/javacc-maven-plugin'...
$ git fetch origin 3fef8960d0693200d06b8a5162c5b5f5e38aaa3b:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/javacc-maven-plugin
 * [new ref]         3fef8960d0693200d06b8a5162c5b5f5e38aaa3b -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 3fef896 Update javapackages test plan to f40