Flag to require that wrapped object has some finalizer

src/guest/napi.rs

@@ -4746,17 +4746,19 @@ fn guest_napi_wrap(
     e: i32,
     obj: i32,
     native_data: i32,
-    _finalize_cb: i32,
+    finalize_cb: i32,
     _finalize_hint: i32,
     ref_ptr: i32,
 ) -> i32 {
     let mut ref_out: u32 = 0;
+    let has_finalize_cb = (finalize_cb != 0) as i32;
     let s = if ref_ptr > 0 {
         unsafe {
             snapi_bridge_wrap(
                 snapi_env(&env, e),
                 obj as u32,
                 native_data as u64,
+                has_finalize_cb,
                 &mut ref_out,
             )
         }
@@ -4766,6 +4768,7 @@ fn guest_napi_wrap(
                 snapi_env(&env, e),
                 obj as u32,
                 native_data as u64,
+                has_finalize_cb,
                 std::ptr::null_mut(),
             )
         }
@@ -4799,21 +4802,29 @@ fn guest_napi_add_finalizer(
     e: i32,
     obj: i32,
     data: i32,
-    _finalize_cb: i32,
+    finalize_cb: i32,
     _finalize_hint: i32,
     ref_ptr: i32,
 ) -> i32 {
     let mut ref_out: u32 = 0;
+    let has_finalize_cb = if finalize_cb != 0 { 1 } else { 0 };
     let s = if ref_ptr > 0 {
         unsafe {
-            snapi_bridge_add_finalizer(snapi_env(&env, e), obj as u32, data as u64, &mut ref_out)
+            snapi_bridge_add_finalizer(
+                snapi_env(&env, e),
+                obj as u32,
+                data as u64,
+                has_finalize_cb,
+                &mut ref_out,
+            )
         }
     } else {
         unsafe {
             snapi_bridge_add_finalizer(
                 snapi_env(&env, e),
                 obj as u32,
                 data as u64,
+                has_finalize_cb,
                 std::ptr::null_mut(),
             )
         }

src/napi_bridge_init.cc

@@ -2044,16 +2044,20 @@ extern "C" int snapi_bridge_get_node_version(SnapiEnvState* env_state, uint32_t*
 // Object wrapping
 // ============================================================
 
+void NAPI_CDECL NoopGuestFinalizer(node_api_nogc_env /*env*/, void* /*data*/, void* /*hint*/) {}
+
 extern "C" int snapi_bridge_wrap(SnapiEnvState* env_state, uint32_t obj_id, uint64_t native_data,
-                                 uint32_t* ref_out) {
+                                 int has_finalize_cb, uint32_t* ref_out) {
   auto* bridge_state = RequireEnvState(env_state);
   if (bridge_state == nullptr) return napi_invalid_arg;
   napi_env env = bridge_state->env;
   napi_value obj = LoadValue(*bridge_state, obj_id);
   if (!obj) return napi_invalid_arg;
+  node_api_basic_finalize finalize_cb =
+      has_finalize_cb ? NoopGuestFinalizer : nullptr;
   napi_ref ref = nullptr;
   napi_status s = napi_wrap(env, obj, (void*)(uintptr_t)native_data,
-                            nullptr, nullptr, ref_out ? &ref : nullptr);
+                            finalize_cb, nullptr, ref_out ? &ref : nullptr);
   if (s != napi_ok) return s;
   if (ref_out) *ref_out = StoreRef(*bridge_state, ref);
   return napi_ok;
@@ -2086,16 +2090,16 @@ extern "C" int snapi_bridge_remove_wrap(SnapiEnvState* env_state, uint32_t obj_i
 }
 
 extern "C" int snapi_bridge_add_finalizer(SnapiEnvState* env_state, uint32_t obj_id, uint64_t data_val,
-                                          uint32_t* ref_out) {
+                                          int has_finalize_cb, uint32_t* ref_out) {
   auto* bridge_state = RequireEnvState(env_state);
   if (bridge_state == nullptr) return napi_invalid_arg;
   napi_env env = bridge_state->env;
   napi_value obj = LoadValue(*bridge_state, obj_id);
   if (!obj) return napi_invalid_arg;
-  // No actual WASM callback for finalizer; just register with nullptr callback
+  if (!has_finalize_cb) return napi_invalid_arg;
   napi_ref ref = nullptr;
   napi_status s = napi_add_finalizer(env, obj, (void*)(uintptr_t)data_val,
-                                     nullptr, nullptr, ref_out ? &ref : nullptr);
+                                     NoopGuestFinalizer, nullptr, ref_out ? &ref : nullptr);
   if (s != napi_ok) return s;
   if (ref_out) *ref_out = StoreRef(*bridge_state, ref);
   return napi_ok;

src/snapi.rs

@@ -876,6 +876,7 @@ unsafe extern "C" {
         env: SnapiEnv,
         obj_id: u32,
         native_data: u64,
+        has_finalize_cb: i32,
         ref_out: *mut u32,
     ) -> i32;
     pub fn snapi_bridge_unwrap(env: SnapiEnv, obj_id: u32, data_out: *mut u64) -> i32;
@@ -884,6 +885,7 @@ unsafe extern "C" {
         env: SnapiEnv,
         obj_id: u32,
         data_val: u64,
+        has_finalize_cb: i32,
         ref_out: *mut u32,
     ) -> i32;
     // Constructor