# File lib/rspec/mocks/space.rb, line 54
      def proxy_for(object)
        id = id_for(object)
        proxies.fetch(id) do
          proxies[id] = case object
                        when NilClass   then ProxyForNil.new
                        when TestDouble then object.__build_mock_proxy
                        else
                          Proxy.new(object)
                        end
        end
      end