$ git clone -n https://src.fedoraproject.org/rpms/java-1.8.0-openjdk.git /var/lib/mock/f40-build-1466376-23686/root/chroot_tmpdir/scmroot/java-1.8.0-openjdk
Cloning into '/var/lib/mock/f40-build-1466376-23686/root/chroot_tmpdir/scmroot/java-1.8.0-openjdk'...
$ git fetch origin f1f4aae9f1954dd65cec28d48580246047b2fe6b:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/java-1.8.0-openjdk
 * [new ref]         f1f4aae9f1954dd65cec28d48580246047b2fe6b -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at f1f4aae Merge branch 'rawhide' into f40