$ git clone -n https://src.fedoraproject.org/rpms/libpng15.git /var/lib/mock/f31-build-59277-28556/root/chroot_tmpdir/scmroot/libpng15
Cloning into '/var/lib/mock/f31-build-59277-28556/root/chroot_tmpdir/scmroot/libpng15'...
$ git reset --hard 4d580617283e7389d1edabcbfe24eb74ce1ac2e3
HEAD is now at 4d58061 - Rebuilt for https://fedoraproject.org/wiki/Fedora_30_Mass_Rebuild