# File lib/bundler/rubygems_integration.rb, line 497
      def validate(spec)
        # Missing summary is downgraded to a warning in later versions,
        # so we set it to an empty string to prevent an exception here.
        spec.summary ||= ""
        Bundler.ui.silence { spec.validate(false) }
      rescue Errno::ENOENT
        nil
      end