$ git clone -n https://src.fedoraproject.org/rpms/rust-copypasta.git /var/lib/mock/f42-build-side-1-3583711-46890/root/chroot_tmpdir/scmroot/rust-copypasta
Cloning into '/var/lib/mock/f42-build-side-1-3583711-46890/root/chroot_tmpdir/scmroot/rust-copypasta'...
$ git fetch origin a1bf2447cfd4b0839107ca5890b488fac6aad542:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-copypasta
 * [new ref]         a1bf2447cfd4b0839107ca5890b488fac6aad542 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at a1bf244 Update to version 0.10.2; Fixes RHBZ#2362306