v10/packages/utils/src/events/abort.ts

/**
 * Compose multiple abort signals into one that aborts when **any** input fires.
 * Uses native `AbortSignal.any` when available, otherwise falls back to a
 * manual `AbortController` composition for Chromium ≤115 and similar runtimes.
 */
export function anyAbortSignal(signals: AbortSignal[]): AbortSignal {
  if ('any' in AbortSignal) {
    return AbortSignal.any(signals);
  }

  const controller = new AbortController();

  for (const signal of signals) {
    if (signal.aborted) {
      controller.abort(signal.reason);
      return controller.signal;
    }

    signal.addEventListener('abort', () => controller.abort(signal.reason), {
      signal: controller.signal,
    });
  }

  return controller.signal;
}

/**
 * Race a promise against an abort signal. Rejects immediately if the signal
 * is already aborted or becomes aborted before the promise settles.
 */
export function abortable<T>(promise: Promise<T>, signal: AbortSignal): Promise<T> {
  if (signal.aborted) {
    return Promise.reject(signal.reason);
  }

  let onAbort: () => void;

  return Promise.race([
    promise,
    new Promise<never>((_, reject) => {
      onAbort = () => reject(signal.reason);
      signal.addEventListener('abort', onAbort, { once: true });
    }),
  ]).finally(() => {
    signal.removeEventListener('abort', onAbort);
  });
}