Changes on mirror value doesn't trigger reactivity

[aguspdana]

Describe the bug

When a mirrored value changes through a reactivity to another value, it doesn't trigger further reactivity on blocks that depend on it or components that indirectly depend on it.

Reproduction

<script>
	let source = 0;
	let mirror = 0;
	$: isMirrorZero = mirror === 0;

	// Changes on mirror doesn't trigger this block when it's changed by syncMirror.
	$: {
		const id = Math.floor(Math.random() * 100);
		console.log(`${id}. source: ${source}; mirror: ${mirror}`)
		setTimeout(() => {console.log(`${id}. mirror later: ${mirror}`)}, 1)
	}
	
	$: syncMirror(source);
	
	function syncMirror(s) {
		if (mirror !== s) {
			mirror = s;
		}
	}

	function handleClick() {
		source++
	}
</script>

<button on:click={handleClick}>
	Source: {source}
</button>
<p>
	Mirror: {mirror}
</p>

{#if isMirrorZero}
	<p>
		This should not appear when mirror is not zero
	</p>
{/if}

Logs

No response

System Info

Repl

Severity

annoyance

[Conduitry]

This is the intended behavior. Duplicate of #3361, #5190, #5848, #5905. #7612, and probably others. See in particular my comment on #5848.