Can I drain the pending queue without running them?

Question

RepoPilot · Accepted Answer

Yes, you can drain the pending queue without running the pending tasks using the `clearQueue()` method [index.d.ts:L20-L28].

When you call `limit.clearQueue()`, it discards all pending promises that are waiting to run without executing them [readme.md:L96-L99]. The method specifically states: "Note: This does not cancel promises that are already running" [readme.md:L102].

By default, when you clear the queue, pending promises are simply discarded and never settle. However, if you want pending tasks to be explicitly rejected instead (to avoid promises hanging indefinitely), you can enable the `rejectOnClear` option when creating the limiter:

```js
const limit = pLimit({concurrency: 1, rejectOnClear: true});
```

With `rejectOnClear: true`, pending promises are rejected with an `AbortError` when `clearQueue()` is called [index.d.ts:L26-L28], which is recommended if you're using `Promise.all()` or similar constructs.

The implementation shows that `clearQueue()` either silently clears the queue or rejects each pending item with an abort error, depending on the `rejectOnClear` setting [index.js:L84-L95].

FOLLOW_UPS:
- How does clearQueue() interact with already running tasks?
- What's the difference between rejectOnClear true and false?
- Can I customize the error type for rejected pending tasks?