$ git clone -n https://src.fedoraproject.org/rpms/rust-lru /var/lib/mock/f42-build-3429433-45391/root/chroot_tmpdir/scmroot/rust-lru
Cloning into '/var/lib/mock/f42-build-3429433-45391/root/chroot_tmpdir/scmroot/rust-lru'...
$ git fetch origin e640d717d54de09061871cc66eb9bedc3195d0a6:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-lru
 * [new ref]         e640d717d54de09061871cc66eb9bedc3195d0a6 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at e640d71 Update to version 0.13.0; Fixes RHBZ#2342471