disable test in async mode

packages/svelte/tests/runtime-legacy/shared.ts

@@ -47,6 +47,8 @@ export interface RuntimeTest<Props extends Record<string, any> = Record<string,
 	skip_mode?: Array<'server' | 'client' | 'hydrate'>;
 	/** Skip if running with process.env.NO_ASYNC */
 	skip_no_async?: boolean;
+	/** Skip if running without process.env.NO_ASYNC */
+	skip_async?: boolean;
 	html?: string;
 	ssrHtml?: string;
 	compileOptions?: Partial<CompileOptions>;
@@ -128,6 +130,10 @@ export function runtime_suite(runes: boolean) {
 				return true;
 			}
 
+			if (async_mode && config.skip_async) {
+				return true;
+			}
+
 			if (variant === 'hydrate') {
 				if (config.mode && !config.mode.includes('hydrate')) return 'no-test';
 				if (config.skip_mode?.includes('hydrate')) return true;

packages/svelte/tests/runtime-runes/samples/untrack-own-deriveds/_config.js

@@ -2,10 +2,8 @@ import { flushSync } from 'svelte';
 import { test } from '../../test';
 
 export default test({
-	// In async mode we _do_ want to run effects that react to their own state changing, so we need to disable async mode here
-	compileOptions: {
-		experimental: { async: false }
-	},
+	// In async mode we _do_ want to run effects that react to their own state changing
+	skip_async: true,
 	test({ assert, target, logs }) {
 		const button = target.querySelector('button');