fix: don't add imports to hoisted event parameters (#12493)

fixes #12489

Author: dummdidumm

.changeset/popular-cups-bathe.md

@@ -0,0 +1,5 @@
+---
+'svelte': patch
+---
+
+fix: don't add imports to hoisted event parameters

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

@@ -544,7 +544,10 @@ function get_hoistable_params(node, context) {
 				!is_prop_source(binding, context.state)
 			) {
 				push_unique(b.id('$$props'));
-			} else {
+			} else if (
+				// imports don't need to be hoisted
+				binding.declaration_kind !== 'import'
+			) {
 				// create a copy to remove start/end tags which would mess up source maps
 				push_unique(b.id(binding.node.name));
 				// rest props are often accessed through the $$props object for optimization reasons,

packages/svelte/tests/runtime-runes/samples/event-import-no-param-hoisting/Component.svelte

@@ -0,0 +1,11 @@
+<script>
+	import { num } from './state.svelte.js';
+	let { foo } = $props();
+
+	function onclick() {
+		foo();
+		console.log(num);
+	}
+</script>
+
+<button {onclick}>click</button>

packages/svelte/tests/runtime-runes/samples/event-import-no-param-hoisting/_config.js

@@ -0,0 +1,14 @@
+import { flushSync } from 'svelte';
+import { test } from '../../test';
+
+export default test({
+	mode: ['client'],
+	test({ assert, logs, target }) {
+		const btn = target.querySelector('button');
+
+		btn?.click();
+		flushSync();
+
+		assert.deepEqual(logs, [1, 1]);
+	}
+});

packages/svelte/tests/runtime-runes/samples/event-import-no-param-hoisting/main.svelte

@@ -0,0 +1,11 @@
+<script>
+	import { num, increment } from './state.svelte.js';
+	import Component from './Component.svelte';
+
+	function foo() {
+		increment();
+		console.log(num);
+	}
+</script>
+
+<Component {foo} />

packages/svelte/tests/runtime-runes/samples/event-import-no-param-hoisting/state.svelte.js

@@ -0,0 +1,5 @@
+export let num = 0;
+
+export function increment() {
+	num += 1;
+}