Svelte 5: $runes reactivity doesn't work inside setTimeout.

[HighFunctioningSociopathSH]

Describe the bug

reactivity is only triggered with assignment inside setTimeout and other methods of updating the $state, for example, the push method of arrays results in no reaction. This seems to happen when using $inspect

Reproduction

  let numbers = $state<number[]>([1, 2, 3]);

  setTimeout(() => {
    // numbers = [1]; This works and $inspect correctly logs the updated value.
    numbers.push(numbers.length + 1) // But this doesn't work and $inspect logs nothing.
  }, 3000);

  $inspect(numbers);

Logs

No response

System Info

System:
    OS: Windows 11 10.0.22621
    CPU: (16) x64 12th Gen Intel(R) Core(TM) i7-12650H
    Memory: 7.82 GB / 15.63 GB
  Binaries:
    Node: 18.14.2 - C:\Program Files\nodejs\node.EXE
    npm: 9.7.1 - C:\Program Files\nodejs\npm.CMD
  Browsers:
    Edge: Chromium (120.0.2210.144)
    Internet Explorer: 11.0.22621.1
  npmPackages:
    svelte: ^5.0.0-next.37 => 5.0.0-next.37

Severity

annoyance

[rmunn]

Note that if you have a <p>numbers: {numbers}</p> element, it updates correctly after the timeout (repro). Only $inspect is failing in this repro.

[rmunn]

Also, it only fails once. If you duplicate that setTimeout three times, you'll see the following logged:

• init [1, 2, 3]
• update [1, 2, 3, 4, 5]
• update [1, 2, 3, 4, 5, 6]

The only update that $inspect fails to log is the first one, where 4 is pushed. Here's another repro that pushes 1000, 2000 and 3000 so it's more obvious which setTimeout call is causing which update. The first setTimeout to run is the one that $inspect doesn't see; the others are correctly showing up in console logs.