update_specs_index (Gem::Indexer)

    # File lib/rubygems/indexer.rb, line 700
      def update_specs_index(index, source, dest)
        specs_index = Marshal.load Gem.read_binary(source)

        index.each do |_, spec|
          platform = spec.original_platform
          platform = Gem::Platform::RUBY if platform.nil? or platform.empty?
          specs_index << [spec.name, spec.version, platform]
        end

        specs_index = compact_specs specs_index.uniq.sort

        open dest, 'wb' do |io|
          Marshal.dump specs_index, io
        end
      end