$ git clone -n https://src.fedoraproject.org/rpms/rust-tikv-jemallocator.git /var/lib/mock/f42-build-side-114849-60997089-6587456/root/chroot_tmpdir/scmroot/rust-tikv-jemallocator
Cloning into '/var/lib/mock/f42-build-side-114849-60997089-6587456/root/chroot_tmpdir/scmroot/rust-tikv-jemallocator'...
$ git fetch origin 24846b71c9538e1cb6df44ccf3c0793b49f909f3:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-tikv-jemallocator
 * [new ref]         24846b71c9538e1cb6df44ccf3c0793b49f909f3 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 24846b7 Initial package (close RHBZ#2366368)