fix: get spread + bind working (#10091)

fixes #10033

Author: dummdidumm

.changeset/stale-books-perform.md

@@ -0,0 +1,5 @@
+---
+'svelte': patch
+---
+
+fix: take into account setters when spreading and binding

packages/svelte/src/internal/client/render.js

@@ -2646,8 +2646,13 @@ const spread_props_handler = {
 			if (typeof p === 'object' && p !== null && key in p) return p[key];
 		}
 	},
-	getOwnPropertyDescriptor() {
-		return { enumerable: true, configurable: true };
+	getOwnPropertyDescriptor(target, key) {
+		let i = target.props.length;
+		while (i--) {
+			let p = target.props[i];
+			if (is_function(p)) p = p();
+			if (typeof p === 'object' && p !== null && key in p) return get_descriptor(p, key);
+		}
 	},
 	has(target, key) {
 		for (let p of target.props) {

packages/svelte/tests/runtime-runes/samples/bind-and-spread/_config.js

@@ -0,0 +1,21 @@
+import { test } from '../../test';
+
+export default test({
+	html: `<button class="foo">0</button><button class="foo">0</button>`,
+
+	async test({ assert, target }) {
+		const [btn1, btn2] = target.querySelectorAll('button');
+
+		await btn1?.click();
+		assert.htmlEqual(
+			target.innerHTML,
+			`<button class="foo">1</button><button class="foo">1</button>`
+		);
+
+		await btn2?.click();
+		assert.htmlEqual(
+			target.innerHTML,
+			`<button class="foo">2</button><button class="foo">2</button>`
+		);
+	}
+});

packages/svelte/tests/runtime-runes/samples/bind-and-spread/button.svelte

@@ -0,0 +1,6 @@
+<script>
+	let { value, ...props } = $props();
+	
+</script>
+
+<button {...props} onclick={() => value++}>{value}</button>

packages/svelte/tests/runtime-runes/samples/bind-and-spread/main.svelte

@@ -0,0 +1,12 @@
+<script>
+	import Button from './button.svelte';
+	
+	let value = $state(0);
+
+	const props = {
+		class: 'foo'
+	};
+</script>
+
+<Button {...props} bind:value />
+<button {...props} onclick={() => value++}>{value}</button>