Function abortableAsyncIterable

async/unstable_abortable.ts:155–183

(
  p: AsyncIterable<T>,
  signal: AbortSignal,
)

}

async function* abortableAsyncIterable<T>(
  p: AsyncIterable<T>,
  signal: AbortSignal,
): AsyncGenerator<T> {
  signal.throwIfAborted();
  const { promise, reject } = Promise.withResolvers<never>();
  const abort = () => reject(signal.reason);
  signal.addEventListener("abort", abort, { once: true });

  const it = p[Symbol.asyncIterator]();
  try {
    while (true) {
      const race = Promise.race([promise, it.next()]);
      race.catch(() => {
        signal.removeEventListener("abort", abort);
      });
      const { done, value } = await race;
      if (done) {
        signal.removeEventListener("abort", abort);
        const result = await it.return?.(value);
        return result?.value;
      }
      yield value;
    }
  } catch (e) {
    await it.return?.();
    throw e;
  }
}