Want string
	Got  string
}

func (e ChecksumMismatch) Error() string {
	return "Bad checksum: Want " + e.Want + " does not match calculated " + e.Got
}

// IsChecksumMismatch matches if 'err' is hash.ChecksumMismatch
func IsChecksumMismatch(err error) bool {
	var herr ChecksumMismatch
	return errors.As(err, &herr)