$ git clone -n https://src.fedoraproject.org/rpms/rust-inferno.git /var/lib/mock/f42-build-60969970-6587122/root/chroot_tmpdir/scmroot/rust-inferno
Cloning into '/var/lib/mock/f42-build-60969970-6587122/root/chroot_tmpdir/scmroot/rust-inferno'...
$ git fetch origin e3f3cb70e2911d5003b59517a1a4fffa3af5213f:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-inferno
 * [new ref]         e3f3cb70e2911d5003b59517a1a4fffa3af5213f -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at e3f3cb7 Update to version 0.12.3; Fixes RHBZ#2376514