Function pLimit

src/utils.ts:1150–1184

(concurrency: number)

 * A lightweight Promise concurrency limiter.
 */
export function pLimit(concurrency: number): Limit {
  if (!Number.isInteger(concurrency) || concurrency <= 0) {
    throw new FirebaseError(`pLimit concurrency must be a positive integer, got ${concurrency}`);
  }

  const queue: Array<() => void> = [];
  let activeCount = 0;

  const next = () => {
    activeCount--;
    if (queue.length > 0) {
      queue.shift()?.();
    }
  };

  return <T>(fn: () => Promise<T>): Promise<T> => {
    return new Promise<T>((resolve, reject) => {
      const run = () => {
        activeCount++;
        try {
          Promise.resolve(fn()).then(resolve, reject).finally(next);
        } catch (err) {
          reject(err);
          next();
        }
      };

      if (activeCount < concurrency) {
        run();
      } else {
        queue.push(run);
      }
    });
  };
}

/**
 * Calculates the Levenshtein distance between two strings.