From 14330bd770aebb1ad79fa88647440de76349dfd4 Mon Sep 17 00:00:00 2001
From: Rich Harris <rich.harris@vercel.com>
Date: Mon, 24 Feb 2025 16:55:07 -0500
Subject: [PATCH] add Promise.withResolvers shim for convenience

---
 playgrounds/sandbox/ssr-common.js | 11 +++++++++++
 playgrounds/sandbox/ssr-dev.js    |  1 +
 playgrounds/sandbox/ssr-prod.js   |  1 +
 3 files changed, 13 insertions(+)
 create mode 100644 playgrounds/sandbox/ssr-common.js

diff --git a/playgrounds/sandbox/ssr-common.js b/playgrounds/sandbox/ssr-common.js
new file mode 100644
index 0000000000..60c6b52eb1
--- /dev/null
+++ b/playgrounds/sandbox/ssr-common.js
@@ -0,0 +1,11 @@
+Promise.withResolvers ??= () => {
+	let resolve;
+	let reject;
+
+	const promise = new Promise((f, r) => {
+		resolve = f;
+		reject = r;
+	});
+
+	return { promise, resolve, reject };
+};
diff --git a/playgrounds/sandbox/ssr-dev.js b/playgrounds/sandbox/ssr-dev.js
index 01ce14e266..e019b234a6 100644
--- a/playgrounds/sandbox/ssr-dev.js
+++ b/playgrounds/sandbox/ssr-dev.js
@@ -5,6 +5,7 @@ import { fileURLToPath } from 'node:url';
 import polka from 'polka';
 import { createServer as createViteServer } from 'vite';
 import { render } from 'svelte/server';
+import './ssr-common.js';
 
 const PORT = process.env.PORT || '5173';
 
diff --git a/playgrounds/sandbox/ssr-prod.js b/playgrounds/sandbox/ssr-prod.js
index 1ed9435249..e8f74ee93a 100644
--- a/playgrounds/sandbox/ssr-prod.js
+++ b/playgrounds/sandbox/ssr-prod.js
@@ -3,6 +3,7 @@ import path from 'node:path';
 import polka from 'polka';
 import { render } from 'svelte/server';
 import App from './src/App.svelte';
+import './ssr-common.js';
 
 const { head, body } = render(App);