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WebSocket events fire synchronously during close() instead of asynchronously #4741
Description
Bug Description
When close() is called on a WebSocket in the CONNECTING state, the error and close events fire synchronously during the close() call, rather than being queued to fire asynchronously after close() returns.
Reproducible By
const { WebSocket } = require('undici');
const ws = new WebSocket('wss://echo.websocket.events/');
let closeReturned = false;
ws.addEventListener('error', () => {
console.log('error event fired, closeReturned =', closeReturned);
});
ws.addEventListener('close', () => {
console.log('close event fired, closeReturned =', closeReturned);
process.exit(0);
});
console.log('Calling close()...');
ws.close();
closeReturned = true;
console.log('close() returned, closeReturned =', closeReturned);
setTimeout(() => {
console.log('Timeout - no events fired');
process.exit(1);
}, 5000);Expected Behavior
Calling close()...
close() returned, closeReturned = true
error event fired, closeReturned = true
close event fired, closeReturned = true
See: https://jsbin.com/butegexadi/edit?html,js,output
This follows from the "queue a task" steps in in the spec: https://websockets.spec.whatwg.org/#:~:text=cleanly%2C-,the%20user%20agent%20must%20queue%20a%20task
Relevant WPTs:
- https://github.com/web-platform-tests/wpt/blob/master/websockets/interfaces/WebSocket/close/close-connecting.html
- https://github.com/web-platform-tests/wpt/blob/master/websockets/interfaces/WebSocket/close/close-connecting-async.any.js
Logs & Screenshots
Actual behavior:
Calling close()...
error event fired, closeReturned = false
close event fired, closeReturned = false
Environment
- Node v25.2.1
- undici 7.18.2
Activity
fix(websocket): fire close event asynchronously when closing in CONNE…
fix: queue WebSocket error/close events when closing CONNECTING socket
KhafraDev commentedon Apr 24, 2026
I am actually going to go insane if 1 more person thinks that their coding agent of choice can correctly fix this in one-shot with no understanding of the issue.
mcollina commentedon Apr 24, 2026
@KhafraDev I do have a broad understanding of the issue and I do not understand how you want it fixed / we do not agree on the fix. It would be best if you took care of iz
KhafraDev commentedon Apr 24, 2026
I wasn't referring to you :) There have been 3 PRs that are completely AI generated that are all wrong for the same reason. It's honestly getting really annoying getting notifications for this issue when people (ie. #5078) cannot take the time to review the changes themselves or even respond without using ai.