From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Samuel Attard <marshallofsound@electronjs.org>
Date: Wed, 8 Mar 2023 13:02:17 -0800
Subject: chore: expose ImportModuleDynamically and
 HostInitializeImportMetaObjectCallback to embedders

This also subtly changes the behavior of shouldNotRegisterESMLoader to ensure that node sets up the handlers
internally but simply avoids setting its own handlers on the Isolate.  This is so that Electron can set it to
its own blended handler between Node and Blink.

Not upstreamable.

diff --git a/lib/internal/modules/esm/utils.js b/lib/internal/modules/esm/utils.js
index 9d6f850f667c5186efe6855bc3d5f5af332bdaa7..8521759e20adf53024e5893dbf3cb36e1752085e 100644
--- a/lib/internal/modules/esm/utils.js
+++ b/lib/internal/modules/esm/utils.js
@@ -30,7 +30,7 @@ const {
   ERR_VM_DYNAMIC_IMPORT_CALLBACK_MISSING,
   ERR_INVALID_ARG_VALUE,
 } = require('internal/errors').codes;
-const { getOptionValue } = require('internal/options');
+const { getOptionValue, getEmbedderOptions } = require('internal/options');
 const {
   loadPreloadModules,
   initializeFrozenIntrinsics,
@@ -280,12 +280,13 @@ let _forceDefaultLoader = false;
  * @param {boolean} [forceDefaultLoader=false] - A boolean indicating disabling custom loaders.
  */
 function initializeESM(forceDefaultLoader = false) {
+  const shouldSetOnIsolate = !getEmbedderOptions().shouldNotRegisterESMLoader;
   _forceDefaultLoader = forceDefaultLoader;
   initializeDefaultConditions();
   // Setup per-realm callbacks that locate data or callbacks that we keep
   // track of for different ESM modules.
-  setInitializeImportMetaObjectCallback(initializeImportMetaObject);
-  setImportModuleDynamicallyCallback(importModuleDynamicallyCallback);
+  setInitializeImportMetaObjectCallback(initializeImportMetaObject, shouldSetOnIsolate);
+  setImportModuleDynamicallyCallback(importModuleDynamicallyCallback, shouldSetOnIsolate);
 }
 
 /**
diff --git a/src/module_wrap.cc b/src/module_wrap.cc
index cdd0ba00eb0cafbc79b816017423f9021ca2979d..6916497f6feb14e482cf5080b57d639ae7292d20 100644
--- a/src/module_wrap.cc
+++ b/src/module_wrap.cc
@@ -875,7 +875,7 @@ MaybeLocal<Module> ModuleWrap::ResolveModuleCallback(
   return module->module_.Get(isolate);
 }
 
-static MaybeLocal<Promise> ImportModuleDynamically(
+MaybeLocal<Promise> ImportModuleDynamically(
     Local<Context> context,
     Local<Data> host_defined_options,
     Local<Value> resource_name,
@@ -947,12 +947,13 @@ void ModuleWrap::SetImportModuleDynamicallyCallback(
   Realm* realm = Realm::GetCurrent(args);
   HandleScope handle_scope(isolate);
 
-  CHECK_EQ(args.Length(), 1);
+  CHECK_EQ(args.Length(), 2);
   CHECK(args[0]->IsFunction());
   Local<Function> import_callback = args[0].As<Function>();
   realm->set_host_import_module_dynamically_callback(import_callback);
 
-  isolate->SetHostImportModuleDynamicallyCallback(ImportModuleDynamically);
+  if (args[1]->IsBoolean() && args[1]->BooleanValue(isolate))
+    isolate->SetHostImportModuleDynamicallyCallback(ImportModuleDynamically);
 }
 
 void ModuleWrap::HostInitializeImportMetaObjectCallback(
@@ -994,13 +995,14 @@ void ModuleWrap::SetInitializeImportMetaObjectCallback(
   Realm* realm = Realm::GetCurrent(args);
   Isolate* isolate = realm->isolate();
 
-  CHECK_EQ(args.Length(), 1);
+  CHECK_EQ(args.Length(), 2);
   CHECK(args[0]->IsFunction());
   Local<Function> import_meta_callback = args[0].As<Function>();
   realm->set_host_initialize_import_meta_object_callback(import_meta_callback);
 
-  isolate->SetHostInitializeImportMetaObjectCallback(
-      HostInitializeImportMetaObjectCallback);
+  if (args[1]->IsBoolean() && args[1]->BooleanValue(isolate))
+    isolate->SetHostInitializeImportMetaObjectCallback(
+        HostInitializeImportMetaObjectCallback);
 }
 
 MaybeLocal<Value> ModuleWrap::SyntheticModuleEvaluationStepsCallback(
diff --git a/src/module_wrap.h b/src/module_wrap.h
index ef4dfd1d6b091d2b0f71b946904a47415b6435ba..862f946a75f2a2949d7eeb7f97e96289beab8078 100644
--- a/src/module_wrap.h
+++ b/src/module_wrap.h
@@ -8,6 +8,7 @@
 #include <unordered_map>
 #include <vector>
 #include "base_object.h"
+#include "node.h"
 #include "v8-script.h"
 
 namespace node {
@@ -33,7 +34,14 @@ enum HostDefinedOptions : int {
   kLength = 9,
 };
 
-class ModuleWrap : public BaseObject {
+NODE_EXTERN v8::MaybeLocal<v8::Promise> ImportModuleDynamically(
+    v8::Local<v8::Context> context,
+    v8::Local<v8::Data> host_defined_options,
+    v8::Local<v8::Value> resource_name,
+    v8::Local<v8::String> specifier,
+    v8::Local<v8::FixedArray> import_assertions);
+
+class NODE_EXTERN ModuleWrap : public BaseObject {
  public:
   enum InternalFields {
     kModuleSlot = BaseObject::kInternalFieldCount,
@@ -91,6 +99,8 @@ class ModuleWrap : public BaseObject {
   static void CreateRequiredModuleFacade(
       const v8::FunctionCallbackInfo<v8::Value>& args);
 
+  static ModuleWrap* GetFromModule(node::Environment*, v8::Local<v8::Module>);
+
  private:
   ModuleWrap(Realm* realm,
              v8::Local<v8::Object> object,
@@ -130,7 +140,6 @@ class ModuleWrap : public BaseObject {
       v8::Local<v8::String> specifier,
       v8::Local<v8::FixedArray> import_attributes,
       v8::Local<v8::Module> referrer);
-  static ModuleWrap* GetFromModule(node::Environment*, v8::Local<v8::Module>);
 
   v8::Global<v8::Module> module_;
   std::unordered_map<std::string, v8::Global<v8::Object>> resolve_cache_;