ensure_required_rubygems_version_met

# File lib/rubygems/installer.rb, line 643
  def ensure_required_rubygems_version_met # :nodoc:
    if rrgv = spec.required_rubygems_version
      unless rrgv.satisfied_by? Gem.rubygems_version
        rg_version = Gem::VERSION
        raise Gem::RuntimeRequirementNotMetError,
          "#{spec.name} requires RubyGems version #{rrgv}. The current RubyGems version is #{rg_version}. " +
          "Try 'gem update --system' to update RubyGems itself."
      end
    end
  end