Function parseEntityDeclaration

xml/_parse_sync.ts:369–512

* Parse and validate an ENTITY declaration syntax. * * We do NOT expand custom entities from DTD * We only support the 5 predefined XML entities (lt, gt, amp, apos, quot). * External entities (SYSTEM/PUBLIC) are also not supported. * * This function validates syntax but does not st

()

   * NDataDecl ::= S 'NDATA' S Name
   */
  function parseEntityDeclaration(): void {
    // Skip whitespace after ENTITY keyword (already validated by caller)
    skipWhitespace();

    // Check for parameter entity marker '%'
    const isParameterEntity = input.charCodeAt(pos) === CC_PERCENT;
    if (isParameterEntity) {
      pos++;
      // Must have whitespace after '%'
      if (pos >= len || !isWhitespace(input.charCodeAt(pos))) {
        error("Missing whitespace after '%' in parameter entity declaration");
      }
      skipWhitespace();
    }

    // Read entity name
    const name = readName();
    if (name === "") {
      error("Missing entity name in ENTITY declaration");
    }

    // Must have whitespace after name
    if (pos >= len || !isWhitespace(input.charCodeAt(pos))) {
      error("Missing whitespace after entity name");
    }
    skipWhitespace();

    // Determine entity definition type
    const code = input.charCodeAt(pos);
    if (code === CC_DQUOTE || code === CC_SQUOTE) {
      // EntityValue - internal entity
      parseQuotedLiteral();

      // Check for SGML-style comment (-- after quoted value)
      skipWhitespace();
      if (
        pos + 1 < len &&
        input.charCodeAt(pos) === CC_DASH &&
        input.charCodeAt(pos + 1) === CC_DASH
      ) {
        error(
          "SGML-style comments (--) are not allowed in XML declarations",
        );
      }
    } else {
      // ExternalID - SYSTEM or PUBLIC
      const kwStart = pos;
      while (
        pos < len &&
        ((input.charCodeAt(pos) >= 65 && input.charCodeAt(pos) <= 90) || // A-Z
          (input.charCodeAt(pos) >= 97 && input.charCodeAt(pos) <= 122)) // a-z
      ) {
        pos++;
      }
      const keyword = input.slice(kwStart, pos);
      const keywordUpper = keyword.toUpperCase();

      // Check for case-sensitivity - must be uppercase