$ git clone -n https://src.fedoraproject.org/rpms/gnome-calculator.git /var/lib/mock/f40-build-802192-143957/root/chroot_tmpdir/scmroot/gnome-calculator
Cloning into '/var/lib/mock/f40-build-802192-143957/root/chroot_tmpdir/scmroot/gnome-calculator'...
$ git fetch origin 97fc9d6412ea1ec48e1cae4c668b76f2c9358111:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/gnome-calculator
 * [new ref]         97fc9d6412ea1ec48e1cae4c668b76f2c9358111 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 97fc9d6 Update to 46.0