Function RescaleWouldCauseDataLoss

cpp/src/arrow/util/basic_decimal.cc:1038–1051

template <class DecimalClass>
static bool RescaleWouldCauseDataLoss(const DecimalClass& value, int32_t delta_scale,
                                      const DecimalClass& multiplier,
                                      DecimalClass* result) {
  if (delta_scale < 0) {
    DCHECK_NE(multiplier, 0);
    DecimalClass remainder;
    auto status = value.Divide(multiplier, result, &remainder);
    DCHECK_EQ(status, DecimalStatus::kSuccess);
    return remainder != 0;
  }

  *result = value * multiplier;
  return (value < 0) ? *result > value : *result < value;
}

template <class DecimalClass>
DecimalStatus DecimalRescale(const DecimalClass& value, int32_t original_scale,