$ git clone -n https://src.fedoraproject.org/rpms/perl-XML-DifferenceMarkup.git /var/lib/mock/f40-build-779685-130430/root/chroot_tmpdir/scmroot/perl-XML-DifferenceMarkup
Cloning into '/var/lib/mock/f40-build-779685-130430/root/chroot_tmpdir/scmroot/perl-XML-DifferenceMarkup'...
$ git fetch origin 2f0077ac71e9cb3af89540dbcae18ca68d2f9f4c:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-XML-DifferenceMarkup
 * [new ref]         2f0077ac71e9cb3af89540dbcae18ca68d2f9f4c -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 2f0077a Build-require coreutils for cp