fix: issue with assiging prop values as defaults of other props (#9985)

* Fix issue on assiging prop values as defaults of other props

* Prettier

* Add changeset

.changeset/itchy-kings-deliver.md

@@ -0,0 +1,5 @@
+---
+'svelte': patch
+---
+
+Fix issue with assigning prop values as defaults of other props

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

@@ -195,6 +195,9 @@ export const javascript_visitors_runes = {
 							id = property.value.left;
 							initial = property.value.right;
 						}
+						initial = initial
+							? /** @type {import('estree').Expression} */ (visit(initial))
+							: undefined;
 
 						assert.equal(id.type, 'Identifier');
 

packages/svelte/tests/runtime-runes/samples/assign-prop-to-prop/Test.svelte

@@ -0,0 +1,9 @@
+<script>
+	let z = 8;
+	let { a, b = a, c = b * b, d = z * b + c } = $props();
+</script>
+
+<p>{a}</p>
+<p>{b}</p>
+<p>{c}</p>
+<p>{d}</p>

packages/svelte/tests/runtime-runes/samples/assign-prop-to-prop/_config.js

@@ -0,0 +1,5 @@
+import { test } from '../../test';
+
+export default test({
+	html: `<p>5</p><p>5</p><p>25</p><p>65</p>`
+});

packages/svelte/tests/runtime-runes/samples/assign-prop-to-prop/main.svelte

@@ -0,0 +1,5 @@
+<script>
+	import Test from './Test.svelte'
+</script>
+
+<Test a={5} />