0004-micropython-webassembly-allow-Asyncify-in-runPythonAsync.patch

From 1111111111111111111111111111111111111111 Mon Sep 17 00:00:00 2001
From: Brad Barnett <brad@pydevices.dev>
Date: Sun, 23 Aug 2026 10:00:00 -0500
Subject: [PATCH] webassembly: allow Asyncify in runPythonAsync

Direct browser ports can suspend inside native imports such as Fetch. Mark the
explicit asynchronous execution API as an Asyncify-aware ccall and await it;
keep runPython synchronous for callers that do not suspend.
---
 ports/webassembly/api.js | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/ports/webassembly/api.js b/ports/webassembly/api.js
index 60d2e82c4..e50c7d6b1 100644
--- a/ports/webassembly/api.js
+++ b/ports/webassembly/api.js
@@ -147,7 +147,7 @@ export async function loadMicroPython(options) {
             Module._free(buf);
             return proxy_convert_mp_to_js_obj_jsside_with_free(value);
         },
-        runPythonAsync(code) {
+        async runPythonAsync(code) {
             const len = Module.lengthBytesUTF8(code);
             const buf = Module._malloc(len + 1);
             Module.stringToUTF8(code, buf, len + 1);
@@ -154,7 +154,8 @@ export async function loadMicroPython(options) {
             const value = Module._malloc(3 * 4);
-            Module.ccall(
+            await Module.ccall(
                 "mp_js_do_exec_async",
                 "number",
                 ["pointer", "number", "pointer"],
                 [buf, len, value],
+                { async: true },
             );
             Module._free(buf);
             const ret = proxy_convert_mp_to_js_obj_jsside_with_free(value);
-- 
2.43.0