Function parseGroup

src/pkg/utils/regex_to_glob.ts:430–649

()

  // ----- Group parsing (alternations, lookaheads, etc.) -----
  // 分组解析（交替 |、前瞻等）
  function parseGroup(): Unit | null {
    const parts: string[] = [];
    let depth = 1,
      buf = "",
      isAlt = false;

    // 处理 (?:...), (?=...), (?!...), (?<=...), (?<!...)
    if (peek() === "?") {
      next();
      const kind: string = next();
      if (kind === ":") {
        // Non-capturing
        // 非捕获
      } else if (kind === "=" || kind === "!") {
        // 前瞻（零宽）
        let laDepth = 1;
        while (i < n && laDepth > 0) {
          const ch2 = next();
          if (ch2 === "\\") {
            if (!next()) return null;
          } else if (ch2 === "(") laDepth++;
          else if (ch2 === ")") laDepth--;
        }
        if (laDepth !== 0) return null;
        return { glob: "", baseGlob: "", canRepeat: false, min: 0, isLiteral: false, varLen: false };
      } else if (kind === "<") {
        const lb = next();
        if (lb === "=" || lb === "!") {
          let lbDepth = 1;
          while (i < n && lbDepth > 0) {
            const ch2 = next();
            if (ch2 === "\\") {
              if (!next()) return null;
            } else if (ch2 === "(") lbDepth++;
            else if (ch2 === ")") lbDepth--;
          }
          if (lbDepth !== 0) return null;
          return { glob: "", baseGlob: "", canRepeat: false, min: 0, isLiteral: false, varLen: false };
        } else {
          buf += "<?" + lb;
        }
      } else {
        buf += "?" + kind;
      }
    }

    // 解析内容并在最外层分割 '|'
    while (i < n && depth > 0) {
      const ch: string = next();
      if (ch === "\\") {
        const esc = next();
        if (!esc) return null;
        // preserve escape while scanning
        // 保留转义
        buf += "\\" + esc;
      } else if (ch === "(") {
        depth++;
        buf += ch;