$ git clone -n https://src.fedoraproject.org/rpms/R-jpeg.git /var/lib/mock/f29-build-1173-484/root/thebuilddir/tmp/scmroot/R-jpeg
Cloning into '/var/lib/mock/f29-build-1173-484/root/thebuilddir/tmp/scmroot/R-jpeg'...
$ git reset --hard ecf7471d205a4e22bb58c63c82baf49230f55248
HEAD is now at ecf7471 - Rebuilt for https://fedoraproject.org/wiki/Fedora_28_Mass_Rebuild