ruby_version

# File lib/rubygems.rb, line 955
  def self.ruby_version
    return @ruby_version if defined? @ruby_version
    version = RUBY_VERSION.dup

    if defined?(RUBY_PATCHLEVEL) && RUBY_PATCHLEVEL != -1
      version << ".#{RUBY_PATCHLEVEL}"
    elsif defined?(RUBY_DESCRIPTION)
      if RUBY_ENGINE == "ruby"
        desc = RUBY_DESCRIPTION[/\Aruby #{Regexp.quote(RUBY_VERSION)}([^ ]+) /, 1]
      else
        desc = RUBY_DESCRIPTION[/\A#{RUBY_ENGINE} #{Regexp.quote(RUBY_ENGINE_VERSION)} \(#{RUBY_VERSION}([^ ]+)\) /, 1]
      end
      version << ".#{desc}" if desc
    end

    @ruby_version = Gem::Version.new version
  end