# File lib/specinfra/command/base/file.rb, line 68
    def check_contains_lines(file, expected_lines, from=nil, to=nil)
      require 'digest/md5'
      from ||= '1'
      to ||= '$'
      sed = "sed -n #{escape(from)},#{escape(to)}p #{escape(file)}"
      head_line = expected_lines.first.chomp
      lines_checksum = Digest::MD5.hexdigest(expected_lines.map(&:chomp).join("\n") + "\n")
      afterwards_length = expected_lines.length - 1
      "#{sed} | grep -A #{escape(afterwards_length)} -F -- #{escape(head_line)} | md5sum | grep -qiw -- #{escape(lines_checksum)}"
    end