$ git clone -n https://src.fedoraproject.org/rpms/R-DelayedArray.git /var/lib/mock/f42-build-side-1-3522753-46188/root/chroot_tmpdir/scmroot/R-DelayedArray
Cloning into '/var/lib/mock/f42-build-side-1-3522753-46188/root/chroot_tmpdir/scmroot/R-DelayedArray'...
$ git fetch origin 1865bd2421981b9608fe9b5c52d0837064ea0d55:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/R-DelayedArray
 * [new ref]         1865bd2421981b9608fe9b5c52d0837064ea0d55 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 1865bd2 R-maint-sig mass rebuild