class Gem::RDoc

def legacy_rdoc *args
  args << @spec.rdoc_options
  args << '--quiet'
  args << @spec.require_paths.clone
  args << @spec.extra_rdoc_files
  args << '--title' << "#{@spec.full_name} Documentation"
  args = args.flatten.map do |arg| arg.to_s end
  delete_legacy_args args if
    Gem::Requirement.new('>= 2.4.0') =~ self.class.rdoc_version
  r = new_rdoc
  verbose { "rdoc #{args.join ' '}" }
  Dir.chdir @spec.full_gem_path do
    begin
      r.document args
    rescue Errno::EACCES => e
      dirname = File.dirname e.message.split("-")[1].strip
      raise Gem::FilePermissionError, dirname
    rescue Interrupt => e
      raise e
    rescue Exception => ex
      alert_error "While generating documentation for #{@spec.full_name}"
      ui.errs.puts "... MESSAGE:   #{ex}"
      ui.errs.puts "... RDOC args: #{args.join(' ')}"
      ui.backtrace ex
      ui.errs.puts "(continuing with the rest of the installation)"
    end
  end
end