From cbf00dd8a13aed42183c6ff2eb83ee42fffd28a9 Mon Sep 17 00:00:00 2001
From: GarboMuffin <muffin@mailbox.org>
Date: Sat, 25 Feb 2023 19:21:01 -0600
Subject: [PATCH] Wrap baked extensions in an IIFE

Closes https://github.com/TurboWarp/packager/issues/636
---
 src/packager/packager.js | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/packager/packager.js b/src/packager/packager.js
index 9f25295..76df82c 100644
--- a/src/packager/packager.js
+++ b/src/packager/packager.js
@@ -1012,7 +1012,11 @@ cd "$(dirname "$0")"
         const url = urlsToFetch[i];
         try {
           const source = await Adapter.fetchExtensionScript(url);
-          const dataURI = `data:text/javascript;,${encodeURIComponent(source)}`;
+          // Wrap the extension in an IIFE so that extensions written for the sandbox are less
+          // likely to cause issues in an unsandboxed environment due to global pollution or
+          // overriding Scratch.*
+          const wrappedSource = `(function(Scratch) { ${source} })(Scratch);`
+          const dataURI = `data:text/javascript;,${encodeURIComponent(wrappedSource)}`;
           finalURLs.push(dataURI);
         } catch (e) {
           finalURLs.push(url);