[fix] handle undefined select value with spread (#6687)

src/compiler/compile/render_dom/wrappers/Element/index.ts

@@ -674,7 +674,7 @@ export default class ElementWrapper extends Wrapper {
 				(${data}.multiple ? @select_options : @select_option)(${this.var}, ${data}.value);
 			`);
 			block.chunks.update.push(b`
-				if (${block.renderer.dirty(Array.from(dependencies))}) (${data}.multiple ? @select_options : @select_option)(${this.var}, ${data}.value);;
+				if (${block.renderer.dirty(Array.from(dependencies))} && 'value' in ${data}) (${data}.multiple ? @select_options : @select_option)(${this.var}, ${data}.value);;
 			`);
 		} else if (this.node.name === 'input' && this.attributes.find(attr => attr.node.name === 'value')) {
 			const type = this.node.get_static_attribute_value('type');

test/runtime/samples/spread-element-select-value-undefined/Select.svelte

@@ -0,0 +1,12 @@
+<script>
+	export let options = [];
+	export let value = "";
+	export let label = "";
+</script>
+
+<select bind:value {...$$restProps}>
+	{#each options as option}
+		<option>{option}</option>
+	{/each}
+</select>
+<p>{label}</p>

test/runtime/samples/spread-element-select-value-undefined/_config.js

@@ -0,0 +1,11 @@
+export default {
+	async test({ assert, component, target, window }) {
+		const select = target.querySelector('select');
+
+		assert.equal(select.value, '1');
+
+		component.label = 'hoge';
+
+		assert.equal(select.value, '1');
+	}
+};

test/runtime/samples/spread-element-select-value-undefined/main.svelte

@@ -0,0 +1,11 @@
+<script>
+	import Select from "./Select.svelte";
+	let value = {
+		a: "1",
+		b: "1",
+	};
+	const options = ["1", "2", "3"];
+	export let label = "test";
+</script>
+
+<Select bind:value={value.a} {options} label={label} />