Function tryParseDateString

bolt/type/TimestampConversion.cpp:205–390

};

DateParseResult tryParseDateString(
    const char* buf,
    size_t len,
    size_t& pos,
    int64_t& daysSinceEpoch,
    int32_t mode,
    bool sparkCompatible = false) {
  bool isValid = true;
  pos = 0;
  if (len == 0) {
    return DateParseResult::kEmptyInput;
  }

  int32_t day = 0;
  int32_t month = -1;
  int32_t year = 0;
  bool yearneg = false;
  int sep;

  // Skip leading spaces.
  while (pos < len && characterIsSpace(buf[pos])) {
    pos++;
  }

  if (pos >= len) {
    return DateParseResult::kEmptyInput;
  }
  if (buf[pos] == '-') {
    yearneg = true;
    pos++;
    if (pos >= len) {
      return DateParseResult::kEmptyYear;
    }
  } else if (buf[pos] == '+') {
    pos++;
    if (pos >= len) {
      return DateParseResult::kEmptyYear;
    }
  }

  if (!characterIsDigit(buf[pos])) {
    return DateParseResult::kInvalidYear;
  }
  // First parse the year.
  int yearDigitNum = 0;
  for (; pos < len && characterIsDigit(buf[pos]); pos++, yearDigitNum++) {
    year = checkedPlus((buf[pos] - '0'), checkedMultiply(year, 10));
    if (year > kMaxYear) {
      break;
    }
  }
  if ((mode & ParseMode::kNonStandardCast) && yearDigitNum < 4) {
    return DateParseResult::kYearTooShort;
  }
  if (yearneg) {
    year = checkedNegate(year);
    if (year < kMinYear) {
      return DateParseResult::kInvalidYear;