From b7625fd42c067b7cd03fea9589ef45349f9dedbe Mon Sep 17 00:00:00 2001
From: 7nik <kifiranet@gmail.com>
Date: Sun, 2 Nov 2025 11:40:32 +0200
Subject: [PATCH] fix: do not spread non-enumerable symbols (#17097)

---
 packages/svelte/src/internal/client/runtime.js           | 2 +-
 .../samples/derived-rest-includes-symbol/_config.js      | 2 +-
 .../samples/derived-rest-includes-symbol/main.svelte     | 9 ++++++---
 3 files changed, 8 insertions(+), 5 deletions(-)

diff --git a/packages/svelte/src/internal/client/runtime.js b/packages/svelte/src/internal/client/runtime.js
index 6485d21ec2..76531d3320 100644
--- a/packages/svelte/src/internal/client/runtime.js
+++ b/packages/svelte/src/internal/client/runtime.js
@@ -778,7 +778,7 @@ export function exclude_from_object(obj, keys) {
 	}
 
 	for (var symbol of Object.getOwnPropertySymbols(obj)) {
-		if (!keys.includes(symbol)) {
+		if (Object.propertyIsEnumerable.call(obj, symbol) && !keys.includes(symbol)) {
 			result[symbol] = obj[symbol];
 		}
 	}
diff --git a/packages/svelte/tests/runtime-runes/samples/derived-rest-includes-symbol/_config.js b/packages/svelte/tests/runtime-runes/samples/derived-rest-includes-symbol/_config.js
index eec60928a2..d0633983d2 100644
--- a/packages/svelte/tests/runtime-runes/samples/derived-rest-includes-symbol/_config.js
+++ b/packages/svelte/tests/runtime-runes/samples/derived-rest-includes-symbol/_config.js
@@ -1,5 +1,5 @@
 import { test } from '../../test';
 
 export default test({
-	html: `<p>42</p>`
+	html: `<p>true false</p>`
 });
diff --git a/packages/svelte/tests/runtime-runes/samples/derived-rest-includes-symbol/main.svelte b/packages/svelte/tests/runtime-runes/samples/derived-rest-includes-symbol/main.svelte
index ee161696e1..2454e98ab7 100644
--- a/packages/svelte/tests/runtime-runes/samples/derived-rest-includes-symbol/main.svelte
+++ b/packages/svelte/tests/runtime-runes/samples/derived-rest-includes-symbol/main.svelte
@@ -1,8 +1,11 @@
 <script>
-	const symbol = Symbol();
+	const symbol1 = Symbol();
+	const symbol2 = Symbol();
+
+	let a = { [symbol1]: 42 };
+	Object.defineProperty(a, symbol2, { enumerable: false, value: "nope" })
 
-	let a = { [symbol]: 42 };
 	let { ...b } = $derived(a);
 </script>
 
-<p>{b[symbol]}</p>
+<p>{symbol1 in b} {symbol2 in b}</p>