Function parseIntegerOrDecimal

http/unstable_structured_fields.ts:792–855

(state: ParserState)

}

function parseIntegerOrDecimal(state: ParserState): BareItem {
  const { input } = state;
  let sign = 1;
  if (peek(state) === "-") {
    state.pos++;
    sign = -1;
  }

  if (!isDigit(peek(state))) {
    throw new SyntaxError(
      `Invalid structured field: expected digit at position ${state.pos}`,
    );
  }

  const intStart = state.pos;
  while (isDigit(peek(state))) {
    state.pos++;
  }
  const intLen = state.pos - intStart;
  if (intLen > MAX_INTEGER_DIGITS) {
    throw new SyntaxError(
      "Invalid structured field: integer too long",
    );
  }

  if (peek(state) === ".") {
    state.pos++; // consume '.'
    if (intLen > MAX_DECIMAL_INTEGER_DIGITS) {
      throw new SyntaxError(
        "Invalid structured field: decimal integer part too long",
      );
    }

    const fracStart = state.pos;
    while (isDigit(peek(state))) {
      state.pos++;
    }
    const fracLen = state.pos - fracStart;
    if (fracLen > MAX_DECIMAL_FRACTIONAL_DIGITS) {
      throw new SyntaxError(
        "Invalid structured field: decimal fractional part too long",
      );
    }

    if (fracLen === 0) {
      throw new SyntaxError(
        "Invalid structured field: decimal requires fractional digits",
      );
    }

    const value = sign * parseFloat(input.slice(intStart, state.pos));
    return { type: "decimal", value };
  }

  const value = sign * parseInt(input.slice(intStart, state.pos), 10);

  if (value < -MAX_INTEGER || value > MAX_INTEGER) {
    throw new SyntaxError(