You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: ext_conf_builder.rb
    path of file: ./repos/truffleruby/lib/mri/rubygems/ext
    
    the code of the file until where you have to start completion: # frozen_string_literal: true
#--
# Copyright 2006 by Chad Fowler, Rich Kilmer, Jim Weirich and others.
# All rights reserved.
# See LICENSE.txt for permissions.
#++

class Gem::Ext::ExtConfBui
    
  def self.build(extension, dest_path, results, args=[], lib_dir=nil, extension_dir=Dir.pwd)
    require "fileutils"
    require "tempfile"

    tmp_dest = Dir.mktmpdir(".gem.", extension_dir)

    # Some versions of `mktmpdir` return absolute paths, which will break make
    # if the paths contain spaces.
    #
    # As such, we convert to a relative path.
    tmp_dest_relative = get_relative_path(tmp_dest.clone, extension_dir)

    destdir = ENV["DESTDIR"]

    begin
      cmd = ruby << File.basename(extension)
      cmd.push(*args)

      run(cmd, results, class_name, extension_dir) do |s, r|
        mkmf_log = File.join(extension_dir, "mkmf.log")
        if File.exist? mkmf_log
          unless s.success?
            r << "To see why this extension failed to compile, please check" \
              " the mkmf.log which can be found here:\n"
            r << "  " + File.join(dest_path, "mkmf.log") + "\n"
          end
          FileUtils.mv mkmf_log, dest_path
        end