From 3c9292642df8006a0e1a4106acffba84c84d7779 Mon Sep 17 00:00:00 2001
From: Ruben Bridgewater <ruben@bridgewater.de>
Date: Fri, 29 Mar 2019 03:21:31 +0100
Subject: [PATCH] module: simpler esm loading
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This simplifies loading the experimental modules. Instead of always
checking for them we should eagerly load the functions in case the
experimental modules flag is passed through.

PR-URL: https://github.com/nodejs/node/pull/26974
Reviewed-By: Gus Caplan <me@gus.host>
Reviewed-By: Michaël Zasso <targos@protonmail.com>
Reviewed-By: Guy Bedford <guybedford@gmail.com>
Signed-off-by: Beth Griggs <Bethany.Griggs@uk.ibm.com>
---
 lib/internal/modules/cjs/loader.js | 20 ++++++++------------
 1 file changed, 8 insertions(+), 12 deletions(-)

diff --git a/lib/internal/modules/cjs/loader.js b/lib/internal/modules/cjs/loader.js
index fcbe16ca4893f8..7564f8176bf91e 100644
--- a/lib/internal/modules/cjs/loader.js
+++ b/lib/internal/modules/cjs/loader.js
@@ -61,13 +61,6 @@ let asyncESM;
 let ModuleJob;
 let createDynamicModule;
 
-function lazyLoadESM() {
-  asyncESM = require('internal/process/esm_loader');
-  ModuleJob = require('internal/modules/esm/module_job');
-  createDynamicModule = require(
-    'internal/modules/esm/create_dynamic_module');
-}
-
 const {
   CHAR_UPPERCASE_A,
   CHAR_LOWERCASE_A,
@@ -673,7 +666,6 @@ Module.prototype.load = function(filename) {
   this.loaded = true;
 
   if (experimentalModules) {
-    if (asyncESM === undefined) lazyLoadESM();
     const ESMLoader = asyncESM.ESMLoader;
     const url = `${pathToFileURL(filename)}`;
     const module = ESMLoader.moduleMap.get(url);
@@ -740,7 +732,6 @@ Module.prototype._compile = function(content, filename) {
       lineOffset: 0,
       displayErrors: true,
       importModuleDynamically: experimentalModules ? async (specifier) => {
-        if (asyncESM === undefined) lazyLoadESM();
         const loader = await asyncESM.loaderPromise;
         return loader.import(specifier, normalizeReferrerURL(filename));
       } : undefined,
@@ -767,7 +758,6 @@ Module.prototype._compile = function(content, filename) {
       const { callbackMap } = internalBinding('module_wrap');
       callbackMap.set(compiledWrapper, {
         importModuleDynamically: async (specifier) => {
-          if (asyncESM === undefined) lazyLoadESM();
           const loader = await asyncESM.loaderPromise;
           return loader.import(specifier, normalizeReferrerURL(filename));
         }
@@ -847,7 +837,6 @@ Module._extensions['.node'] = function(module, filename) {
 };
 
 if (experimentalModules) {
-  if (asyncESM === undefined) lazyLoadESM();
   Module._extensions['.mjs'] = function(module, filename) {
     throw new ERR_REQUIRE_ESM(filename);
   };
@@ -857,7 +846,6 @@ if (experimentalModules) {
 Module.runMain = function() {
   // Load the main module--the command line argument.
   if (experimentalModules) {
-    if (asyncESM === undefined) lazyLoadESM();
     asyncESM.loaderPromise.then((loader) => {
       return loader.import(pathToFileURL(process.argv[1]).pathname);
     })
@@ -940,3 +928,11 @@ Module._initPaths();
 
 // Backwards compatibility
 Module.Module = Module;
+
+// We have to load the esm things after module.exports!
+if (experimentalModules) {
+  asyncESM = require('internal/process/esm_loader');
+  ModuleJob = require('internal/modules/esm/module_job');
+  createDynamicModule = require(
+    'internal/modules/esm/create_dynamic_module');
+}