$ git clone -n https://src.fedoraproject.org/rpms/rust-fail.git /var/lib/mock/f40-build-2036274-48015/root/chroot_tmpdir/scmroot/rust-fail
Cloning into '/var/lib/mock/f40-build-2036274-48015/root/chroot_tmpdir/scmroot/rust-fail'...
$ git fetch origin daef18dbabfe26f486fa06c15c78713a1911dac4:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-fail
 * [new ref]         daef18dbabfe26f486fa06c15c78713a1911dac4 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at daef18d Regenerate with rust2rpm v25