module Chef::Mixin::Checksum

def checksum(file)
  Chef::Digester.checksum_for_file(file)
end

def checksum_match?(ref_checksum, diff_checksum)
  return false if ref_checksum.nil? || diff_checksum.nil?
  ref_checksum.casecmp?(diff_checksum)
end

def short_cksum(checksum)
  return "none" if checksum.nil?
  checksum.slice(0, 6)
end