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useTracker problem - Can't set timers inside simulations

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#396 18 comments 0 reactions 0 assignees View on GitHub

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Assessment

Difficulty
4/5
Estimated time
3-5 days
Newbie friendliness
52/100
Issue type
Bug
Clarity
Mostly clear
Activity status
Active
Tech stack
javascript
Domain
frontend

Research direction

Reproduce the transition from a null to non-null contact, then inspect the useTracker.ts paths at lines 81 and 163 shown in the stack traces, including useTrackerClient and useTrackerDev. Done means the transition no longer raises "Can't set timers inside simulations" and the tracker can proceed through the reported subscription scenario.

Written by the indexing model from the issue text.

Description

bug

I'm using useTracker like this:

<div>{!contact ? null : (
  <AsyncValue
    subscription={{
      name: 'mail.contactStats',
      args: [contact.ID],
      query: () => MailStats.findOne({ _id: `for-contact-${contact.ID}` }),
    }}
  />
)}</div

export function AsyncValue({ promise, subscription, render, children, onError }) {
  const [error, setError] = useState(null);
  const { name, args, query } = subscription;
  const value = useTracker(
    () => {
      LOG('METEOR TRACKER?', subscription);
      if (error) return undefined; // otherwise we get an infinite loop trying to resubscribe
      
      // I COMMENTED MY WHOLE CODE TO NARROW DOWN THE PROBLEM, IT STILL APPEARS
      // const sub = Meteor.subscribe(name, ...args, {
      //   onStop: error => {
      //     if (onError) {
      //       DEBUG(`AsyncValue subscription error, sending to onError:`, error);
      //       onError(error, setError);
      //     } else {
      //       if (error) console.error('AsyncValue Subscription error:', error);
      //       setError(error);
      //     }
      //   },
      // });
      // DEBUG(`sub: ready=${sub.ready()}, entries:`, query);
      // return sub.ready() ? query() : undefined;
      return undefined;
    }
    []
  );
  DEBUG(`sub value:`, value);

  const renderValue = () => (render ? render(value) : value);
  return <>{value !== undefined ? renderValue() : placeholder()}</>;
}

Works fine if contact is set from the start - but whenever contact changes from being null to non-null, this error occurs:

Uncaught Error: Can't set timers inside simulations
    at withoutInvocation (meteor.js?hash=3fe70c93a2fcd225dc5cc6572b8c3e39756a507b:621:13)
    at bindAndCatch (meteor.js?hash=3fe70c93a2fcd225dc5cc6572b8c3e39756a507b:633:33)
    at Meteor.defer (meteor.js?hash=3fe70c93a2fcd225dc5cc6572b8c3e39756a507b:694:24)
    at useTracker.ts:163:12
    at mountMemo (modules.js?hash=bfdeb58d2ee948751f18b6466ad43663c2847a1e:133794:19)
    at Object.useMemo (modules.js?hash=bfdeb58d2ee948751f18b6466ad43663c2847a1e:134090:16)
    at useMemo (modules.js?hash=bfdeb58d2ee948751f18b6466ad43663c2847a1e:113407:21)
    at useTrackerWithDeps (useTracker.ts:137:3)
    at useTrackerClient (useTracker.ts:206:12)
    at useTrackerDev (useTracker.ts:244:16)

Also tried useTracker with subscription as dep (same error as above) and without deps - which causes this error:

Uncaught Error: Can't set timers inside simulations
    at withoutInvocation (meteor.js?hash=3fe70c93a2fcd225dc5cc6572b8c3e39756a507b:621:13)
    at bindAndCatch (meteor.js?hash=3fe70c93a2fcd225dc5cc6572b8c3e39756a507b:633:33)
    at Meteor.defer (meteor.js?hash=3fe70c93a2fcd225dc5cc6572b8c3e39756a507b:694:24)
    at useTrackerNoDeps (useTracker.ts:81:12)
    at useTrackerClient (useTracker.ts:204:12)
    at useTrackerDev (useTracker.ts:244:16)
Dominant language
JavaScript
Stars
576
Forks
167
Avg merge
4d 3h
Merged PRs (30d)
1

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