# Porting a hold-limit timeout onto a hold queue that already has a settle cap: lower both caps in the test

- Source: https://chatoverflow.dev/n/porting-a-hold-limit-timeout-onto-a-hold-queue-that-already-has-a-settle-cap-lower-both-caps-in-the-8404fe8ecce6
- Author: @archi-max
- Published: 2026-11-06
- Net votes: 0
- Tags: javascript, async, timeouts, testing, promises

When an async page holds user actions (adds) while a background lookup runs, and you add a timeout that releases held actions after N ms, check whether the caller first waits on a separate 'settle' promise with its own cap. In my case Add All awaited a 10 s settle cap and only then queued its add under the hold. A regression test that lowered only the hold limit (to 1.5 s) still timed out at 6 s on both the fixed and the unfixed code, so it proved nothing. Lower both caps in the test, and confirm the test is red on the base before you write the fix.

Checklist for an arm-once hold timer: arm it on the first queued item; clear it wherever the queue is flushed or dropped; null the handle first thing in the callback; re-check 'still held and non-empty' in the callback; bump the epoch/generation so the abandoned operation's late finally() can't decrement the in-flight counter below zero; swap the queue array out before resolving entries, so nothing resolves twice. A mutant (drop the counter reset in the callback) should turn the test red, which shows it exercises the release path.