From eb2c68d2aeade4c6e4e01526f69e5a7b18970dd2 Mon Sep 17 00:00:00 2001
From: Joyee Cheung <joyeec9h3@gmail.com>
Date: Mon, 25 May 2026 00:18:00 +0200
Subject: [PATCH] module: load ESM helpers eagerly in the snapshot

Since the ESM loader is captured in the snapshot now, there's
no need to lazy load the helpers. Load them eagerly to capture
them into the snapshot. This also reduces the noise coming out
of --print-bytecode since we no longer compile the helper
functions at run time.

Signed-off-by: Joyee Cheung <joyeec9h3@gmail.com>
---
 lib/internal/modules/esm/loader.js      | 28 ++++---------------------
 test/parallel/test-bootstrap-modules.js |  2 ++
 2 files changed, 6 insertions(+), 24 deletions(-)

diff --git a/lib/internal/modules/esm/loader.js b/lib/internal/modules/esm/loader.js
index 34a9393ac18f01..73132ad5b2a6c4 100644
--- a/lib/internal/modules/esm/loader.js
+++ b/lib/internal/modules/esm/loader.js
@@ -14,7 +14,8 @@ const {
   hardenRegExp,
 } = primordials;
 
-
+const { LoadCache, ResolveCache } = require('internal/modules/esm/module_map');
+const { ModuleJob, ModuleJobSync } = require('internal/modules/esm/module_job');
 // This is needed to avoid cycles in esm/resolve <-> cjs/loader
 const {
   kIsExecuting,
@@ -85,24 +86,6 @@ const { isPromise } = require('internal/util/types');
  * @typedef {import('url').URL} URL
  */
 
-/**
- * Lazy loads the module_map module and returns a new instance of ResolveCache.
- * @returns {import('./module_map.js').ResolveCache}
- */
-function newResolveCache() {
-  const { ResolveCache } = require('internal/modules/esm/module_map');
-  return new ResolveCache();
-}
-
-/**
- * Generate a load cache (to store the final result of a load-chain for a particular module).
- * @returns {import('./module_map.js').LoadCache}
- */
-function newLoadCache() {
-  const { LoadCache } = require('internal/modules/esm/module_map');
-  return new LoadCache();
-}
-
 const { translators } = require('internal/modules/esm/translators');
 const { defaultResolve } = require('internal/modules/esm/resolve');
 const { defaultLoadSync, throwUnknownModuleFormat } = require('internal/modules/esm/load');
@@ -161,12 +144,12 @@ class ModuleLoader {
   /**
    * Registry of resolved specifiers
    */
-  #resolveCache = newResolveCache();
+  #resolveCache = new ResolveCache();
 
   /**
    * Registry of loaded modules, akin to `require.cache`
    */
-  loadCache = newLoadCache();
+  loadCache = new LoadCache();
 
   /**
    * @see {AsyncLoaderHooks.isForAsyncLoaderHookWorker}
@@ -238,7 +221,6 @@ class ModuleLoader {
    * @returns {Promise<object>} The module object.
    */
   async executeModuleJob(url, wrap, isEntryPoint = false) {
-    const { ModuleJob } = require('internal/modules/esm/module_job');
     const module = await onImport.tracePromise(async () => {
       const job = new ModuleJob(this, url, undefined, wrap, kEvaluationPhase, false, false, kImportInImportedESM);
       this.loadCache.set(url, undefined, job);
@@ -357,7 +339,6 @@ class ModuleLoader {
     const wrap = compileSourceTextModule(url, source, kUser);
     const inspectBrk = (isMain && getOptionValue('--inspect-brk'));
 
-    const { ModuleJobSync } = require('internal/modules/esm/module_job');
     job = new ModuleJobSync(this, url, kEmptyObject, wrap, kEvaluationPhase, isMain, inspectBrk,
                             kImportInRequiredESM);
     this.loadCache.set(url, kImplicitTypeAttribute, job);
@@ -587,7 +568,6 @@ class ModuleLoader {
       assert(moduleOrModulePromise instanceof ModuleWrap, `Expected ModuleWrap for loading ${url}`);
     }
 
-    const { ModuleJob, ModuleJobSync } = require('internal/modules/esm/module_job');
     // TODO(joyeecheung): use ModuleJobSync for kRequireInImportedCJS too.
     const ModuleJobCtor = (requestType === kImportInRequiredESM ? ModuleJobSync : ModuleJob);
     const isMain = (parentURL === undefined);
diff --git a/test/parallel/test-bootstrap-modules.js b/test/parallel/test-bootstrap-modules.js
index 92bf3be1f612ff..69f1d9f44c9c6c 100644
--- a/test/parallel/test-bootstrap-modules.js
+++ b/test/parallel/test-bootstrap-modules.js
@@ -133,6 +133,8 @@ if (isMainThread) {
     'NativeModule internal/modules/esm/load',
     'NativeModule internal/modules/esm/resolve',
     'NativeModule internal/modules/esm/translators',
+    'NativeModule internal/modules/esm/module_job',
+    'NativeModule internal/modules/esm/module_map',
     'NativeModule url',
   ].forEach(expected.beforePreExec.add.bind(expected.beforePreExec));
 } else {  // Worker.