# File lib/mkrf/rakehelper.rb, line 42
def setup_extension(dir, extension)
  ext = "ext/#{dir}"
  ext_so = "#{ext}/#{extension}.#{Config::CONFIG['DLEXT']}"
  ext_files = FileList[
    "#{ext}/*.c",
    "#{ext}/*.h",
    "#{ext}/mkrf_conf.rb",
    "#{ext}/Rakefile",
    "lib"
  ] 

  task "lib" do
    directory "lib"
  end

  desc "Builds just the #{extension} extension"
  task extension.to_sym => ["#{ext}/Rakefile", ext_so ]

  file "#{ext}/Rakefile" => ["#{ext}/mkrf_conf.rb"] do
    mkrf_conf "#{ext}"
  end

  file ext_so => ext_files do
    rake "#{ext}"
    cp ext_so, "lib"
  end
end