Svelte 5: The $derived rune of type boolean, does not trigger the $effect rune.

[e-is-me-squared]

Describe the bug

When referencing a $derived rune from a class instance in the $effect rune. The effect is not triggered, on change, when that value is a boolean.

Reproduction

<script>
	import {someLogic} from './SomeLogic.svelte';
	function increment() {
		someLogic.trigger();
	}

	let lokalDerived = $derived(someLogic.someValue > 3);

	$effect(() => {
		console.log(someLogic.someValue);
	});
	$effect(() => {
		// Does not trigger
		console.log('class trigger', someLogic.isAboveThree)
	});
	$effect(() => {
		// Does Triggers
		console.log('lokal trigger', lokalDerived)
	});
	
</script>

<button on:click={increment}>
	clicks: {someLogic.someValue}
	
	<!-- Adding this line below, will make the effect above trigger as i should -->
	<!-- has clicked more then 3 times {someLogic.isAboveThree} -->
</button>

class SomeLogic {
	someValue = $state(0);
	isAboveThree = $derived(this.someValue > 3)
	trigger(){
		this.someValue++;
	}
}

export const someLogic = new SomeLogic();

REPL: Tap the clicks button 4 times and have a look at the log.

Logs

No response

System Info

REPL

Severity

annoyance

[SikandarJODD]

It triggers when you add this :

class SomeLogic {
	someValue = $state(0);
	isAboveThree = $derived(this.someValue > 3)
	trigger(){
		this.someValue++;
		this.isAboveThree;       // This code
	}
}

export const someLogic = new SomeLogic();