From 0216108195b4d77a93387abd04c2d05fb21b733d Mon Sep 17 00:00:00 2001
From: Martok <martok@martoks-place.de>
Date: Sun, 22 Jan 2023 00:10:50 +0100
Subject: [PATCH] No issue - Throw error when resolving or rejecting promise
 returned by async function with testing function

Based-on: m-c 1418106
---
 js/src/builtin/Promise.cpp          |  7 +++++++
 js/src/builtin/Promise.h            |  3 +++
 js/src/builtin/TestingFunctions.cpp | 10 ++++++++++
 3 files changed, 20 insertions(+)

diff --git a/js/src/builtin/Promise.cpp b/js/src/builtin/Promise.cpp
index faba010950..2cd26d87d6 100644
--- a/js/src/builtin/Promise.cpp
+++ b/js/src/builtin/Promise.cpp
@@ -2577,6 +2577,13 @@ js::CreatePromiseObjectForAsync(JSContext* cx, HandleValue generatorVal)
     return promise;
 }
 
+bool
+js::IsPromiseForAsync(JSObject* promise)
+{
+    return promise->is<PromiseObject>() &&
+           PromiseHasAnyFlag(promise->as<PromiseObject>(), PROMISE_FLAG_ASYNC);
+}
+
 // ES 2018 draft 25.5.5.2 steps 3.f, 3.g.
 MOZ_MUST_USE bool
 js::AsyncFunctionThrown(JSContext* cx, Handle<PromiseObject*> resultPromise)
diff --git a/js/src/builtin/Promise.h b/js/src/builtin/Promise.h
index 04cc46920f..d8d178891a 100644
--- a/js/src/builtin/Promise.h
+++ b/js/src/builtin/Promise.h
@@ -141,6 +141,9 @@ PromiseResolve(JSContext* cx, HandleObject constructor, HandleValue value);
 MOZ_MUST_USE PromiseObject*
 CreatePromiseObjectForAsync(JSContext* cx, HandleValue generatorVal);
 
+MOZ_MUST_USE bool
+IsPromiseForAsync(JSObject* promise);
+
 MOZ_MUST_USE bool
 AsyncFunctionReturned(JSContext* cx, Handle<PromiseObject*> resultPromise, HandleValue value);
 
diff --git a/js/src/builtin/TestingFunctions.cpp b/js/src/builtin/TestingFunctions.cpp
index 48cdc827ba..914d3b989b 100644
--- a/js/src/builtin/TestingFunctions.cpp
+++ b/js/src/builtin/TestingFunctions.cpp
@@ -1398,6 +1398,11 @@ ResolvePromise(JSContext* cx, unsigned argc, Value* vp)
             return false;
     }
 
+    if (IsPromiseForAsync(promise)) {
+        JS_ReportErrorASCII(cx, "async function's promise shouldn't be manually resolved");
+        return false;
+    }
+
     bool result = JS::ResolvePromise(cx, promise, resolution);
     if (result)
         args.rval().setUndefined();
@@ -1425,6 +1430,11 @@ RejectPromise(JSContext* cx, unsigned argc, Value* vp)
             return false;
     }
 
+    if (IsPromiseForAsync(promise)) {
+        JS_ReportErrorASCII(cx, "async function's promise shouldn't be manually rejected");
+        return false;
+    }
+
     bool result = JS::RejectPromise(cx, promise, reason);
     if (result)
         args.rval().setUndefined();