module: initialize module_wrap.callbackMap during pre-execution

Since the bootstrap does not actually use ESM at all, there
is no need to create this map so early. This patch moves
the initialization of the map to pre-execution,
so that the only binding loaded in loaders is native_module.
In addition, switch to SafeWeakMap.

PR-URL: https://github.com/nodejs/node/pull/27323
Reviewed-By: Gus Caplan <me@gus.host>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>

lib/internal/bootstrap/loaders.js

@@ -135,9 +135,6 @@ let internalBinding;
   };
 }
 
-// Create this WeakMap in js-land because V8 has no C++ API for WeakMap.
-internalBinding('module_wrap').callbackMap = new WeakMap();
-
 // Think of this as module.exports in this file even though it is not
 // written in CommonJS style.
 const loaderExports = {

lib/internal/bootstrap/pre_execution.js

@@ -1,6 +1,6 @@
 'use strict';
 
-const { Object } = primordials;
+const { Object, SafeWeakMap } = primordials;
 
 const { getOptionValue } = require('internal/options');
 const { Buffer } = require('buffer');
@@ -342,6 +342,9 @@ function initializeCJSLoader() {
 }
 
 function initializeESMLoader() {
+  // Create this WeakMap in js-land because V8 has no C++ API for WeakMap.
+  internalBinding('module_wrap').callbackMap = new SafeWeakMap();
+
   const experimentalModules = getOptionValue('--experimental-modules');
   const experimentalVMModules = getOptionValue('--experimental-vm-modules');
   if (experimentalModules || experimentalVMModules) {

lib/internal/modules/esm/create_dynamic_module.js

@@ -2,7 +2,6 @@
 
 const { ArrayPrototype } = primordials;
 
-const { ModuleWrap, callbackMap } = internalBinding('module_wrap');
 const debug = require('internal/util/debuglog').debuglog('esm');
 
 const createDynamicModule = (exports, url = '', evaluate) => {
@@ -21,7 +20,7 @@ import.meta.exports.${name} = {
 
 import.meta.done();
 `;
-
+  const { ModuleWrap, callbackMap } = internalBinding('module_wrap');
   const m = new ModuleWrap(source, `${url}`);
   m.link(() => 0);
   m.instantiate();

lib/internal/modules/esm/translators.js

@@ -7,7 +7,6 @@ const {
 } = primordials;
 
 const { NativeModule } = require('internal/bootstrap/loaders');
-const { ModuleWrap, callbackMap } = internalBinding('module_wrap');
 const {
   stripShebang,
   stripBOM
@@ -45,6 +44,7 @@ async function importModuleDynamically(specifier, { url }) {
 translators.set('module', async function moduleStrategy(url) {
   const source = `${await readFileAsync(new URL(url))}`;
   debug(`Translating StandardModule ${url}`);
+  const { ModuleWrap, callbackMap } = internalBinding('module_wrap');
   const module = new ModuleWrap(stripShebang(source), url);
   callbackMap.set(module, {
     initializeImportMeta,

lib/internal/process/esm_loader.js

@@ -1,8 +1,5 @@
 'use strict';
 
-const {
-  callbackMap,
-} = internalBinding('module_wrap');
 const {
   ERR_VM_DYNAMIC_IMPORT_CALLBACK_MISSING,
 } = require('internal/errors').codes;
@@ -14,6 +11,7 @@ const {
 } = require('internal/vm/source_text_module');
 
 exports.initializeImportMetaObject = function(wrap, meta) {
+  const { callbackMap } = internalBinding('module_wrap');
   if (callbackMap.has(wrap)) {
     const { initializeImportMeta } = callbackMap.get(wrap);
     if (initializeImportMeta !== undefined) {
@@ -23,6 +21,7 @@ exports.initializeImportMetaObject = function(wrap, meta) {
 };
 
 exports.importModuleDynamicallyCallback = async function(wrap, specifier) {
+  const { callbackMap } = internalBinding('module_wrap');
   if (callbackMap.has(wrap)) {
     const { importModuleDynamically } = callbackMap.get(wrap);
     if (importModuleDynamically !== undefined) {

lib/internal/vm/source_text_module.js

@@ -25,16 +25,16 @@ const {
   validateString
 } = require('internal/validators');
 
+const binding = internalBinding('module_wrap');
 const {
   ModuleWrap,
-  callbackMap,
   kUninstantiated,
   kInstantiating,
   kInstantiated,
   kEvaluating,
   kEvaluated,
   kErrored,
-} = internalBinding('module_wrap');
+} = binding;
 
 const STATUS_MAP = {
   [kUninstantiated]: 'uninstantiated',
@@ -116,7 +116,7 @@ class SourceTextModule {
     linkingStatusMap.set(this, 'unlinked');
     wrapToModuleMap.set(wrap, this);
 
-    callbackMap.set(wrap, {
+    binding.callbackMap.set(wrap, {
       initializeImportMeta,
       importModuleDynamically: importModuleDynamically ? async (...args) => {
         const m = await importModuleDynamically(...args);

lib/vm.js

@@ -29,7 +29,6 @@ const {
   isContext: _isContext,
   compileFunction: _compileFunction
 } = internalBinding('contextify');
-const { callbackMap } = internalBinding('module_wrap');
 const {
   ERR_INVALID_ARG_TYPE,
   ERR_VM_MODULE_NOT_MODULE,
@@ -100,6 +99,7 @@ class Script extends ContextifyScript {
       }
       const { wrapMap, linkingStatusMap } =
         require('internal/vm/source_text_module');
+      const { callbackMap } = internalBinding('module_wrap');
       callbackMap.set(this, { importModuleDynamically: async (...args) => {
         const m = await importModuleDynamically(...args);
         if (isModuleNamespaceObject(m)) {