added test

packages/svelte/tests/runtime-browser/samples/attribute-spreading-with-events/_config.js

@@ -0,0 +1,14 @@
+import { test } from '../../assert';
+const tick = () => Promise.resolve();
+
+export default test({
+	async test({ assert, target }) {
+		await tick();
+		/** @type {HTMLElement} */
+		const el = target.querySelector('.test');
+		el.addEventListener('animationend', async () => {
+			await tick();
+			assert.exists(document.querySelector('.result'));
+		});
+	}
+});

packages/svelte/tests/runtime-browser/samples/attribute-spreading-with-events/main.svelte

@@ -0,0 +1,39 @@
+<script>
+	let animationEnded = $state(false);
+	const obj = {};
+</script>
+
+<div
+  {...obj}
+  class="test"
+  ontransitionend={(e) => {
+     // doesnt matter
+  }}
+  onanimationend={(e) => {
+    animationEnded = true;
+  }}
+>
+</div>
+
+{#if animationEnded}
+	<span class="result">
+		animation ended
+	</span>
+{/if}
+
+<style>
+	.test {
+	  width: 10rem;
+	  height: 10rem;
+	  background-color: red;
+	  animation: test-animation 10ms;
+	}
+	@keyframes test-animation {
+	    from {
+	      opacity: 0;
+	    }
+	    to {
+	      opacity: 1;
+	    }
+	}
+</style>