nodejs-github-bot · Oct 30, 2025 · Sep 20, 2025 · Sep 20, 2025 · Sep 20, 2025 · Sep 20, 2025
diff --git a/benchmark/napi/create_object_with_properties/.gitignore b/benchmark/napi/create_object_with_properties/.gitignore
@@ -0,0 +1 @@
+build/
diff --git a/benchmark/napi/create_object_with_properties/binding.cc b/benchmark/napi/create_object_with_properties/binding.cc
@@ -0,0 +1,116 @@
+#include <assert.h>
+#include <node_api.h>
+#include <string>
+
+struct BenchmarkParams {
+  napi_value count_val;
+  napi_value bench_obj;
+  napi_value start_fn;
+  napi_value end_fn;
+  uint32_t count;
+};
+
+static BenchmarkParams ParseBenchmarkArgs(napi_env env,
+                                          const napi_callback_info info) {
+  BenchmarkParams params;
+  size_t argc = 4;
+  napi_value args[4];
+  napi_get_cb_info(env, info, &argc, args, nullptr, nullptr);
+
+  params.count_val = args[0];
+  params.bench_obj = args[1];
+  params.start_fn = args[2];
+  params.end_fn = args[3];
+
+  napi_get_value_uint32(env, params.count_val, &params.count);
+  return params;
+}
+
+static napi_value global_names[20];
+static napi_value global_values[20];
+static bool global_properties_initialized = false;
+
+// Creating with many options because complains are when ~20 properties
+static void InitializeTestProperties(napi_env env) {
+  if (global_properties_initialized) return;
+
+  for (int i = 0; i < 20; i++) {
+    std::string name = "foo" + std::to_string(i);
+    napi_create_string_utf8(
+        env, name.c_str(), NAPI_AUTO_LENGTH, &global_names[i]);
+    napi_create_string_utf8(
+        env, name.c_str(), NAPI_AUTO_LENGTH, &global_values[i]);
+  }
+  global_properties_initialized = true;
+}
+
+static napi_value CreateObjectWithPropertiesNew(napi_env env,
+                                                napi_callback_info info) {
+  BenchmarkParams params = ParseBenchmarkArgs(env, info);
+
+  InitializeTestProperties(env);
+
+  napi_value null_prototype;
+  napi_get_null(env, &null_prototype);
+
+  napi_call_function(
+      env, params.bench_obj, params.start_fn, 0, nullptr, nullptr);
+
+  for (uint32_t i = 0; i < params.count; i++) {
+    napi_value obj;
+    napi_create_object_with_properties(
+        env, null_prototype, global_names, global_values, 20, &obj);
+  }
+
+  napi_call_function(
+      env, params.bench_obj, params.end_fn, 1, &params.count_val, nullptr);
+
+  return nullptr;
+}
+
+static napi_value CreateObjectWithPropertiesOld(napi_env env,
+                                                napi_callback_info info) {
+  BenchmarkParams params = ParseBenchmarkArgs(env, info);
+
+  InitializeTestProperties(env);
+
+  napi_call_function(
+      env, params.bench_obj, params.start_fn, 0, nullptr, nullptr);
+
+  for (uint32_t i = 0; i < params.count; i++) {
+    napi_value obj;
+    napi_create_object(env, &obj);
+    for (int j = 0; j < 20; j++) {
+      napi_set_property(env, obj, global_names[j], global_values[j]);
+    }
+  }
+
+  napi_call_function(
+      env, params.bench_obj, params.end_fn, 1, &params.count_val, nullptr);
+
+  return nullptr;
+}
+
+NAPI_MODULE_INIT() {
+  napi_property_descriptor desc[] = {
+      {"createObjectWithPropertiesNew",
+       0,
+       CreateObjectWithPropertiesNew,
+       0,
+       0,
+       0,
+       napi_default,
+       0},
+      {"createObjectWithPropertiesOld",
+       0,
+       CreateObjectWithPropertiesOld,
+       0,
+       0,
+       0,
+       napi_default,
+       0},
+  };
+
+  napi_define_properties(env, exports, sizeof(desc) / sizeof(desc[0]), desc);
+  return exports;
+}
diff --git a/benchmark/napi/create_object_with_properties/binding.gyp b/benchmark/napi/create_object_with_properties/binding.gyp
@@ -0,0 +1,9 @@
+{
+  'targets': [
+    {
+      'target_name': 'binding',
+      'sources': [ 'binding.cc' ],
+      'defines': ['NAPI_EXPERIMENTAL']
+    }
+  ]
+}
diff --git a/benchmark/napi/create_object_with_properties/index.js b/benchmark/napi/create_object_with_properties/index.js
@@ -0,0 +1,24 @@
+'use strict';
+
+const common = require('../../common.js');
+
+let binding;
+try {
+  binding = require(`./build/${common.buildType}/binding`);
+} catch {
+  console.error(`${__filename}: Binding failed to load`);
+  process.exit(0);
+}
+
+const bench = common.createBenchmark(main, {
+  n: [1e2, 1e3, 1e4, 1e5, 1e6],
+  method: ['new', 'old'],
+});
+
+function main({ n, method }) {
+  if (method === 'new') {
+    binding.createObjectWithPropertiesNew(n, bench, bench.start, bench.end);
+  } else {
+    binding.createObjectWithPropertiesOld(n, bench, bench.start, bench.end);
+  }
+}
diff --git a/doc/api/n-api.md b/doc/api/n-api.md
@@ -2637,6 +2637,43 @@ It is the equivalent of doing `new Object()` in JavaScript.
 The JavaScript `Object` type is described in [Section object type][] of the
 ECMAScript Language Specification.
 
+#### `napi_create_object_with_properties`
+
+<!-- YAML
+added: REPLACEME
+-->
+
+> Stability: 1 - Experimental
+
+```cpp
+napi_status napi_create_object_with_properties(napi_env env,
+                                               napi_value prototype_or_null,
+                                               const napi_value* property_names,
+                                               const napi_value* property_values,
+                                               size_t property_count,
+                                               napi_value* result)
+```
+
+* `[in] env`: The environment that the API is invoked under.
+* `[in] prototype_or_null`: The prototype object for the new object. Can be a
+  `napi_value` representing a JavaScript object to use as the prototype, a
+  `napi_value` representing JavaScript `null`, or a `nullptr` that will be converted to `null`.
+* `[in] property_names`: Array of `napi_value` representing the property names.
+* `[in] property_values`: Array of `napi_value` representing the property values.
+* `[in] property_count`: Number of properties in the arrays.
+* `[out] result`: A `napi_value` representing a JavaScript `Object`.
+
+Returns `napi_ok` if the API succeeded.
+
+This API creates a JavaScript `Object` with the specified prototype and
+properties. This is more efficient than calling `napi_create_object` followed
+by multiple `napi_set_property` calls, as it can create the object with all
+properties atomically, avoiding potential V8 map transitions.
+
+The arrays `property_names` and `property_values` must have the same length
+specified by `property_count`. The properties are added to the object in the
+order they appear in the arrays.
+
 #### `napi_create_symbol`
 
 <!-- YAML

diff --git a/src/js_native_api.h b/src/js_native_api.h
@@ -78,6 +78,17 @@ NAPI_EXTERN napi_status NAPI_CDECL napi_get_boolean(napi_env env,
 // Methods to create Primitive types/Objects
 NAPI_EXTERN napi_status NAPI_CDECL napi_create_object(napi_env env,
                                                       napi_value* result);
+#ifdef NAPI_EXPERIMENTAL
+#define NODE_API_EXPERIMENTAL_HAS_CREATE_OBJECT_WITH_PROPERTIES
+NAPI_EXTERN napi_status NAPI_CDECL
+napi_create_object_with_properties(napi_env env,
+                                   napi_value prototype_or_null,
+                                   napi_value* property_names,
+                                   napi_value* property_values,
+                                   size_t property_count,
+                                   napi_value* result);
+#endif  // NAPI_EXPERIMENTAL
+
 NAPI_EXTERN napi_status NAPI_CDECL napi_create_array(napi_env env,
                                                      napi_value* result);
 NAPI_EXTERN napi_status NAPI_CDECL

diff --git a/src/js_native_api_v8.cc b/src/js_native_api_v8.cc
@@ -1591,6 +1591,50 @@ napi_status NAPI_CDECL napi_create_object(napi_env env, napi_value* result) {
   return napi_clear_last_error(env);
 }
 
+napi_status NAPI_CDECL
+napi_create_object_with_properties(napi_env env,
+                                   napi_value prototype_or_null,
+                                   napi_value* property_names,
+                                   napi_value* property_values,
+                                   size_t property_count,
+                                   napi_value* result) {
+  CHECK_ENV_NOT_IN_GC(env);
+  CHECK_ARG(env, result);
+
+  if (property_count > 0) {
+    CHECK_ARG(env, property_names);
+    CHECK_ARG(env, property_values);
+  }
+
+  v8::Local<v8::Value> v8_prototype_or_null;
+  if (prototype_or_null == nullptr) {
+    v8_prototype_or_null = v8::Null(env->isolate);
+  } else {
+    v8_prototype_or_null = v8impl::V8LocalValueFromJsValue(prototype_or_null);
+  }
+
+  v8::LocalVector<v8::Name> v8_names(env->isolate, property_count);
+  v8::LocalVector<v8::Value> v8_values(env->isolate, property_count);
+
+  for (size_t i = 0; i < property_count; i++) {
+    v8::Local<v8::Value> name_value =
+        v8impl::V8LocalValueFromJsValue(property_names[i]);
+    RETURN_STATUS_IF_FALSE(env, name_value->IsName(), napi_name_expected);
+    v8_names[i] = name_value.As<v8::Name>();
+    v8_values[i] = v8impl::V8LocalValueFromJsValue(property_values[i]);
+  }
+
+  v8::Local<v8::Object> obj = v8::Object::New(env->isolate,
+                                              v8_prototype_or_null,
+                                              v8_names.data(),
+                                              v8_values.data(),
+                                              property_count);
+
+  RETURN_STATUS_IF_FALSE(env, !obj.IsEmpty(), napi_generic_failure);
+  *result = v8impl::JsValueFromV8LocalValue(obj);
+  return napi_clear_last_error(env);
+}
+
 napi_status NAPI_CDECL napi_create_array(napi_env env, napi_value* result) {
   CHECK_ENV_NOT_IN_GC(env);
   CHECK_ARG(env, result);

diff --git a/test/js-native-api/test_object/binding.gyp b/test/js-native-api/test_object/binding.gyp
@@ -5,7 +5,10 @@
       "sources": [
         "test_null.c",
         "test_object.c"
-      ]
+      ],
+      "defines": [
+        "NAPI_EXPERIMENTAL"
+      ],
     },
     {
       "target_name": "test_exceptions",

diff --git a/test/js-native-api/test_object/test.js b/test/js-native-api/test_object/test.js
@@ -5,7 +5,6 @@ const assert = require('assert');
 // Testing api calls for objects
 const test_object = require(`./build/${common.buildType}/test_object`);
 
-
 const object = {
   hello: 'world',
   array: [
@@ -391,3 +390,21 @@ assert.deepStrictEqual(test_object.TestGetProperty(), {
     delete obj.x;
   }, /Cannot delete property 'x' of #<Object>/);
 }
+
+{
+  const objectWithProperties = test_object.TestCreateObjectWithProperties();
+  assert.strictEqual(typeof objectWithProperties, 'object');
+  assert.strictEqual(objectWithProperties.name, 'Foo');
+  assert.strictEqual(objectWithProperties.age, 42);
+  assert.strictEqual(objectWithProperties.active, true);
+
+  const emptyObject = test_object.TestCreateObjectWithPropertiesEmpty();
+  assert.strictEqual(typeof emptyObject, 'object');
+  assert.strictEqual(Object.keys(emptyObject).length, 0);
+
+  const objectWithCustomPrototype = test_object.TestCreateObjectWithCustomPrototype();
+  assert.strictEqual(typeof objectWithCustomPrototype, 'object');
+  assert.deepStrictEqual(Object.getOwnPropertyNames(objectWithCustomPrototype), ['value']);
+  assert.strictEqual(objectWithCustomPrototype.value, 42);
+  assert.strictEqual(typeof objectWithCustomPrototype.test, 'function');
+}