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feat: add support for requiring basic finalizers (#1568)
* feat: add support for requiring basic finalizers * Address review comments - Use passive voice in existing and new docs - Revert unnecessary change
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‎.gitignore

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/benchmark/build
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/benchmark/src
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/test/addon_build/addons
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/test/require_basic_finalizers/addons
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/.vscode
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# ignore node-gyp generated files outside its build directory

‎doc/finalization.md

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@@ -8,7 +8,9 @@ provide more efficient memory management, optimizations, improved execution, or
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other benefits.
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In general, it is best to use basic finalizers whenever possible (eg. when
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access to JavaScript is _not_ needed).
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access to JavaScript is _not_ needed). The
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`NODE_ADDON_API_REQUIRE_BASIC_FINALIZERS` preprocessor directive can be defined
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to ensure that all finalizers are basic.
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## Finalizers
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‎doc/setup.md

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@@ -81,12 +81,23 @@ To use **Node-API** in a native module:
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At build time, the Node-API back-compat library code will be used only when the
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targeted node version *does not* have Node-API built-in.
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The preprocessor directive `NODE_ADDON_API_DISABLE_DEPRECATED` can be defined at
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compile time before including `napi.h` to skip the definition of deprecated APIs.
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The `NODE_ADDON_API_DISABLE_DEPRECATED` preprocessor directive can be defined at
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compile time before including `napi.h` to skip the definition of deprecated
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APIs.
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By default, throwing an exception on a terminating environment (eg. worker
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threads) will cause a fatal exception, terminating the Node process. This is to
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provide feedback to the user of the runtime error, as it is impossible to pass
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the error to JavaScript when the environment is terminating. In order to bypass
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this behavior such that the Node process will not terminate, define the
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preprocessor directive `NODE_API_SWALLOW_UNTHROWABLE_EXCEPTIONS`.
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the error to JavaScript when the environment is terminating. The
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`NODE_API_SWALLOW_UNTHROWABLE_EXCEPTIONS` preprocessor directive can be defined
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to bypass this behavior, such that the Node process will not terminate.
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Various Node-API constructs provide a mechanism to run a callback in response to
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a garbage collection event of that object. These callbacks are called
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[_finalizers_]. Some finalizers have restrictions on the type of Node-APIs
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available within the callback. node-addon-api provides convenience helpers that
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bypass this limitation, but may cause the add-on to run less efficiently. The
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`NODE_ADDON_API_REQUIRE_BASIC_FINALIZERS` preprocessor directive can be defined
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to disable the convenience helpers.
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[_finalizers_]: ./finalization.md

‎napi-inl.h

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static inline void Wrapper(node_api_nogc_env env,
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void* data,
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void* finalizeHint) NAPI_NOEXCEPT {
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#ifdef NODE_ADDON_API_REQUIRE_BASIC_FINALIZERS
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static_assert(false,
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"NODE_ADDON_API_REQUIRE_BASIC_FINALIZERS defined: Finalizer "
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"must be basic.");
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#endif
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napi_status status =
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node_api_post_finalizer(env, WrapperGC, data, finalizeHint);
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NAPI_FATAL_IF_FAILED(
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static inline void WrapperWithHint(node_api_nogc_env env,
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void* data,
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void* finalizeHint) NAPI_NOEXCEPT {
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#ifdef NODE_ADDON_API_REQUIRE_BASIC_FINALIZERS
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static_assert(false,
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"NODE_ADDON_API_REQUIRE_BASIC_FINALIZERS defined: Finalizer "
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"must be basic.");
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#endif
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napi_status status =
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node_api_post_finalizer(env, WrapperGCWithHint, data, finalizeHint);
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NAPI_FATAL_IF_FAILED(

‎test/require_basic_finalizers/index.js

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'use strict';
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const { promisify } = require('util');
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const exec = promisify(require('child_process').exec);
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const { copy, remove } = require('fs-extra');
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const path = require('path');
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const assert = require('assert');
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async function test () {
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const addon = 'require-basic-finalizers';
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const ADDON_FOLDER = path.join(__dirname, 'addons', addon);
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await remove(ADDON_FOLDER);
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await copy(path.join(__dirname, 'tpl'), ADDON_FOLDER);
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console.log(' >Building addon');
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// Fail when NODE_ADDON_API_REQUIRE_BASIC_FINALIZERS is enabled
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await assert.rejects(exec('npm --require-basic-finalizers install', {
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cwd: ADDON_FOLDER
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}), 'Addon unexpectedly compiled successfully');
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// Succeed when NODE_ADDON_API_REQUIRE_BASIC_FINALIZERS is not enabled
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return assert.doesNotReject(exec('npm install', {
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cwd: ADDON_FOLDER
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}));
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}
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module.exports = (function () {
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// This test will only run under an experimental version test.
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const isExperimental = Number(process.env.NAPI_VERSION) === 2147483647;
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if (isExperimental) {
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return test();
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} else {
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console.log(' >Skipped (non-experimental test run)');
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}
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})();

‎test/require_basic_finalizers/tpl/.npmrc

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package-lock=false

‎test/require_basic_finalizers/tpl/addon.cc

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#include <napi.h>
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Napi::Object Init(Napi::Env env, Napi::Object exports) {
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exports.Set(
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"external",
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Napi::External<int>::New(
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env, new int(1), [](Napi::Env /*env*/, int* data) { delete data; }));
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return exports;
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}
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NODE_API_MODULE(NODE_GYP_MODULE_NAME, Init)

‎test/require_basic_finalizers/tpl/binding.gyp

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{
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'target_defaults': {
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'include_dirs': [
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"<!(node -p \"require('node-addon-api').include_dir\")"
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],
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'variables': {
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'NAPI_VERSION%': "<!(node -p \"process.env.NAPI_VERSION || process.versions.napi\")",
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'require_basic_finalizers': "<!(node -p \"process.env['npm_config_require_basic_finalizers']\")",
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},
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'conditions': [
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['NAPI_VERSION!=""', { 'defines': ['NAPI_VERSION=<@(NAPI_VERSION)'] } ],
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['NAPI_VERSION==2147483647', { 'defines': ['NAPI_EXPERIMENTAL'] } ],
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['require_basic_finalizers=="true"', {
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'defines': ['NODE_ADDON_API_REQUIRE_BASIC_FINALIZERS'],
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}],
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['OS=="mac"', {
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'cflags+': ['-fvisibility=hidden'],
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'xcode_settings': {
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'OTHER_CFLAGS': ['-fvisibility=hidden']
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}
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}]
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],
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'sources': [
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'addon.cc',
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],
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},
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'targets': [
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{
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'target_name': 'addon',
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'defines': [
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'NAPI_CPP_EXCEPTIONS'
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],
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'cflags!': [ '-fno-exceptions' ],
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'cflags_cc!': [ '-fno-exceptions' ],
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'msvs_settings': {
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'VCCLCompilerTool': {
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'ExceptionHandling': 1,
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'EnablePREfast': 'true',
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},
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},
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'xcode_settings': {
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'CLANG_CXX_LIBRARY': 'libc++',
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'MACOSX_DEPLOYMENT_TARGET': '10.7',
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'GCC_ENABLE_CPP_EXCEPTIONS': 'YES',
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},
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}
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]
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}

‎test/require_basic_finalizers/tpl/index.js

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'use strict';
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module.exports = require('bindings')('addon');

‎test/require_basic_finalizers/tpl/package.json

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{
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"name": "addon",
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"version": "0.0.0",
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"description": "Node.js addon",
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"private": true,
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"scripts": {},
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"dependencies": {
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"node-addon-api": "file:../../../../"
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},
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"gypfile": true
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}

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