$ git clone -n https://src.fedoraproject.org/rpms/perl-Diff-LibXDiff.git /var/lib/mock/f41-build-817003-150570/root/chroot_tmpdir/scmroot/perl-Diff-LibXDiff
Cloning into '/var/lib/mock/f41-build-817003-150570/root/chroot_tmpdir/scmroot/perl-Diff-LibXDiff'...
$ git fetch origin 8f5e001f48170a87370b8477a30291fdb14124e9:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-Diff-LibXDiff
 * [new ref]         8f5e001f48170a87370b8477a30291fdb14124e9 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 8f5e001 Perl 5.40 rebuild