class Concourse::Pipeline

def generate
  Tempfile.create(["pipeline", ".yml"]) do |f|
    f.write erbify_file(erb_filename, working_directory: directory)
    f.close
    if ytt
      ytt_args = ["-f #{f.path}"]
      ytt_args << "-f #{File.expand_path(File.join(File.dirname(__FILE__), "ytt"))}"
      ytt_args << "-f #{File.join(directory, ytt)}" if ytt.is_a?(String)
      sh ["ytt", ytt_args, "> #{filename}"].flatten.join(" ")
    else
      FileUtils.mv f.path, filename, force: true
    end
  end
end