$ git clone -n https://src.fedoraproject.org/rpms/ruby.git /var/lib/mock/f33-build-123746-39137/root/chroot_tmpdir/scmroot/ruby
Cloning into '/var/lib/mock/f33-build-123746-39137/root/chroot_tmpdir/scmroot/ruby'...
$ git reset --hard 40937c8a7a54a6baba830a46b121dbf988ccdc3c
HEAD is now at 40937c8 Install Racc it by default.