Function validateLabel

out/cli.cjs:3215–3301

(label, {
      checkHyphens,
      checkBidi,
      checkJoiners,
      transitionalProcessing,
      useSTD3ASCIIRules,
      isBidi
    })

      return processed;
    }
    function validateLabel(label, {
      checkHyphens,
      checkBidi,
      checkJoiners,
      transitionalProcessing,
      useSTD3ASCIIRules,
      isBidi
    }) {
      if (label.length === 0) {
        return true;
      }
      if (label.normalize("NFC") !== label) {
        return false;
      }
      const codePoints = Array.from(label);
      if (checkHyphens) {
        if (codePoints[2] === "-" && codePoints[3] === "-" || (label.startsWith("-") || label.endsWith("-"))) {
          return false;
        }
      }
      if (!checkHyphens) {
        if (label.startsWith("xn--")) {
          return false;
        }
      }
      if (label.includes(".")) {
        return false;
      }
      if (regexes.combiningMarks.test(codePoints[0])) {
        return false;
      }
      for (const ch of codePoints) {
        const codePoint = ch.codePointAt(0);
        const [status] = findStatus(codePoint);
        if (transitionalProcessing) {
          if (status !== STATUS_MAPPING.valid) {
            return false;
          }
        } else if (status !== STATUS_MAPPING.valid && status !== STATUS_MAPPING.deviation) {
          return false;
        }
        if (useSTD3ASCIIRules && codePoint <= 127) {
          if (!/^(?:[a-z]|[0-9]|-)$/u.test(ch)) {
            return false;
          }
        }
      }
      if (checkJoiners) {
        let last = 0;
        for (const [i3, ch] of codePoints.entries()) {
          if (ch === "\u200C" || ch === "\u200D") {
            if (i3 > 0) {
              if (regexes.combiningClassVirama.test(codePoints[i3 - 1])) {
                continue;
              }
              if (ch === "\u200C") {
                const next = codePoints.indexOf("\u200C", i3 + 1);
                const test2 = next < 0 ? codePoints.slice(last) : codePoints.slice(last, next);