fix: visit expression when destructuring state declarations (#16081)

Author: paoloricciuti

.changeset/hip-penguins-unite.md

@@ -0,0 +1,5 @@
+---
+'svelte': patch
+---
+
+fix: visit expression when destructuring state declarations

packages/svelte/src/compiler/phases/3-transform/client/visitors/VariableDeclaration.js

@@ -148,7 +148,7 @@ export function VariableDeclaration(node, context) {
 					const { inserts, paths } = extract_paths(declarator.id, tmp);
 
 					declarations.push(
-						b.declarator(tmp, value),
+						b.declarator(tmp, /** @type {Expression} */ (context.visit(value))),
 						...inserts.map(({ id, value }) => {
 							id.name = context.state.scope.generate('$$array');
 							context.state.transform[id.name] = { read: get_value };

packages/svelte/tests/runtime-runes/samples/destructure-state-from-props/Child.svelte

@@ -0,0 +1,6 @@
+<script>
+	let { data } = $props();
+	let { foo } = $state(data);
+</script>
+
+{foo}

packages/svelte/tests/runtime-runes/samples/destructure-state-from-props/_config.js

@@ -0,0 +1,5 @@
+import { test } from '../../test';
+
+export default test({
+	html: `bar`
+});

packages/svelte/tests/runtime-runes/samples/destructure-state-from-props/main.svelte

@@ -0,0 +1,5 @@
+<script>
+	import Child from './Child.svelte';
+</script>
+
+<Child data={{ foo: 'bar' }} />