checkDigit method

  1. @override
int checkDigit(
  1. String data
)
override

Computes the check digit from data.

Implementation

@override
int checkDigit(String data) {
  if (data.length < 4) {
    throw ArgumentError(
      'Must not be null and must contain at least 4 digits',
    );
  }

  final sum = _compute(data, hasCheckDigit: false);
  return ((sum / 10).ceil() * 10) - sum;
}