From 738e6a9d276426034a4f1055eb3759aa0ec8a4f8 Mon Sep 17 00:00:00 2001
From: Samir <samirrangwalla1@outlook.com>
Date: Sun, 20 Sep 2026 17:18:51 -0400
Subject: [PATCH 1/2] Return false instead of error with undefined receiver in
 Reflect.set

---
 quickjs.c        | 7 +++++++
 tests/bug1730.js | 5 +++++
 2 files changed, 12 insertions(+)
 create mode 100644 tests/bug1730.js

diff --git a/quickjs.c b/quickjs.c
index 6ca030b9f..cc9ec6e30 100644
--- a/quickjs.c
+++ b/quickjs.c
@@ -10556,9 +10556,15 @@ static int JS_SetPropertyInternal2(JSContext *ctx, JSValueConst obj, JSAtom prop
 
     switch(JS_VALUE_GET_TAG(this_obj)) {
     case JS_TAG_NULL:
+        if (JS_IsObject(obj)) {
+            goto primitive_receiver;
+        }
         JS_ThrowTypeErrorAtom(ctx, "cannot set property '%s' of null", prop);
         goto fail;
     case JS_TAG_UNDEFINED:
+        if (JS_IsObject(obj)) {
+            goto primitive_receiver;
+        }
         JS_ThrowTypeErrorAtom(ctx, "cannot set property '%s' of undefined", prop);
         goto fail;
     case JS_TAG_OBJECT:
@@ -10568,6 +10574,7 @@ static int JS_SetPropertyInternal2(JSContext *ctx, JSValueConst obj, JSAtom prop
             break;
         goto retry2;
     default:
+    primitive_receiver:
         if (JS_VALUE_GET_TAG(obj) != JS_TAG_OBJECT)
             obj = JS_GetPrototypePrimitive(ctx, obj);
         p = NULL;
diff --git a/tests/bug1730.js b/tests/bug1730.js
new file mode 100644
index 000000000..a81e3c485
--- /dev/null
+++ b/tests/bug1730.js
@@ -0,0 +1,5 @@
+import { assert } from "./assert.js";
+
+assert(Reflect.set({ set x(v) {} }, "x", 1, null), true);
+assert(Reflect.set({}, "x", 1, undefined), false);
+assert(Reflect.set({}, "x", 1, null), false);
\ No newline at end of file

From 7ad9bba8904f85be3bb56dec36bea4e6ac85f986 Mon Sep 17 00:00:00 2001
From: Samir Rangwalla <samirrangwalla1@outlook.com>
Date: Fri, 2 Oct 2026 16:12:19 -0400
Subject: [PATCH 2/2] Move primitive_receiver label down to avoid redundant if
 statement

---
 quickjs.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/quickjs.c b/quickjs.c
index cc9ec6e30..fb1ed674e 100644
--- a/quickjs.c
+++ b/quickjs.c
@@ -10574,9 +10574,10 @@ static int JS_SetPropertyInternal2(JSContext *ctx, JSValueConst obj, JSAtom prop
             break;
         goto retry2;
     default:
-    primitive_receiver:
         if (JS_VALUE_GET_TAG(obj) != JS_TAG_OBJECT)
             obj = JS_GetPrototypePrimitive(ctx, obj);
+    
+    primitive_receiver:
         p = NULL;
         p1 = JS_VALUE_GET_OBJ(obj);
         goto prototype_lookup;