install

# File lib/rubygems/request_set.rb, line 146
  def install options, &block # :yields: request, installer
    if dir = options[:install_dir]
      requests = install_into dir, false, options, &block
      return requests
    end

    @prerelease = options[:prerelease]

    requests = []

    sorted_requests.each do |req|
      if req.installed? then
        req.spec.spec.build_extensions

        if @always_install.none? { |spec| spec == req.spec.spec } then
          yield req, nil if block_given?
          next
        end
      end

      spec =
        begin
          req.spec.install options do |installer|
            yield req, installer if block_given?
          end
        rescue Gem::RuntimeRequirementNotMetError => e
          recent_match = req.spec.set.find_all(req.request).sort_by(&:version).reverse_each.find do |s|
            s = s.spec
            s.required_ruby_version.satisfied_by?(Gem.ruby_version) && s.required_rubygems_version.satisfied_by?(Gem.rubygems_version)
          end
          if recent_match
            suggestion = "The last version of #{req.request} to support your Ruby & RubyGems was #{recent_match.version}. Try installing it with `gem install #{recent_match.name} -v #{recent_match.version}`"
            suggestion += " and then running the current command again" unless @always_install.include?(req.spec.spec)
          else
            suggestion = "There are no versions of #{req.request} compatible with your Ruby & RubyGems"
            suggestion += ". Maybe try installing an older version of the gem you're looking for?" unless @always_install.include?(req.spec.spec)
          end
          e.suggestion = suggestion
          raise
        end

      requests << spec
    end

    return requests if options[:gemdeps]

    specs = requests.map do |request|
      case request
      when Gem::Resolver::ActivationRequest then
        request.spec.spec
      else
        request
      end
    end

    require 'rubygems/dependency_installer'
    inst = Gem::DependencyInstaller.new options
    inst.installed_gems.replace specs

    Gem.done_installing_hooks.each do |hook|
      hook.call inst, specs
    end unless Gem.done_installing_hooks.empty?

    requests
  end