module: refactor commonjs typescript loader

This commit refactors the CommonJS loader to remove TypeScript-specific
extensions from the require.extensions object for compatibility with
libraries that depended on it to initialize extenal TypeScript loaders.
PR-URL: #58657
Refs: nodejs/typescript#37
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Joyee Cheung <joyeec9h3@gmail.com>
Reviewed-By: Pietro Marchini <pietro.marchini94@gmail.com>
Reviewed-By: Xuguang Mei <meixuguang@gmail.com>

Author: marco-ippolito

lib/internal/modules/cjs/loader.js

@@ -454,17 +454,6 @@ function initializeCJS() {
 // TODO(joyeecheung): deprecate this in favor of a proper hook?
 Module.runMain=
 require('internal/modules/run_main').executeUserEntryPoint;
-
-consttsEnabled=getOptionValue('--experimental-strip-types');
-if(tsEnabled){
-Module._extensions['.cts']=loadCTS;
-Module._extensions['.ts']=loadTS;
-}
-if(getOptionValue('--experimental-require-module')){
-if(tsEnabled){
-Module._extensions['.mts']=loadMTS;
-}
-}
 }
 
 // Given a module name, and a list of paths to test, returns the first
@@ -670,31 +659,6 @@ function resolveExports(nmPath, request, conditions) {
 }
 }
 
-// We don't cache this in case user extends the extensions.
-functiongetDefaultExtensions(){
-letextensions=ObjectKeys(Module._extensions);
-consttsEnabled=getOptionValue('--experimental-strip-types');
-if(tsEnabled){
-// remove .ts and .cts from the default extensions
-// to avoid extensionless require of .ts and .cts files.
-extensions=ArrayPrototypeFilter(extensions,(ext)=>
-(ext!=='.ts'||Module._extensions['.ts']!==loadTS)&&
-(ext!=='.cts'||Module._extensions['.cts']!==loadCTS),
-);
-}
-
-if(!getOptionValue('--experimental-require-module')){
-returnextensions;
-}
-
-if(tsEnabled){
-extensions=ArrayPrototypeFilter(extensions,(ext)=>
-ext!=='.mts'||Module._extensions['.mts']!==loadMTS,
-);
-}
-returnextensions;
-}
-
 /**
  * Get the absolute path to a module.
  * @param {string} request Relative or absolute file path
@@ -786,7 +750,7 @@ Module._findPath = function(request, paths, isMain, conditions = getCjsCondition
 if(!filename){
 // Try it with each of the extensions
 if(exts===undefined){
-exts=getDefaultExtensions();
+exts=ObjectKeys(Module._extensions);
 }
 filename=tryExtensions(basePath,exts,isMain);
 }
@@ -795,7 +759,7 @@ Module._findPath = function(request, paths, isMain, conditions = getCjsCondition
 if(!filename&&rc===1){// Directory.
 // try it with each of the extensions at "index"
 if(exts===undefined){
-exts=getDefaultExtensions();
+exts=ObjectKeys(Module._extensions);
 }
 filename=tryPackage(basePath,exts,isMain,request);
 }
@@ -1460,12 +1424,6 @@ Module.prototype.load = function(filename) {
 
 constextension=findLongestRegisteredExtension(filename);
 
-if(getOptionValue('--experimental-strip-types')){
-if(StringPrototypeEndsWith(filename,'.mts')&&!Module._extensions['.mts']){
-thrownewERR_REQUIRE_ESM(filename,true);
-}
-}
-
 Module._extensions[extension](this,filename);
 this.loaded=true;
 
@@ -1777,55 +1735,6 @@ function loadSource(mod, filename, formatFromNode) {
 return{source: mod[kModuleSource],format: mod[kFormat]};
 }
 
-/**
- * Built-in handler for `.mts` files.
- * @param {Module} mod CJS module instance
- * @param {string} filename The file path of the module
- */
-functionloadMTS(mod,filename){
-constloadResult=loadSource(mod,filename,'module-typescript');
-mod._compile(loadResult.source,filename,loadResult.format);
-}
-
-/**
- * Built-in handler for `.cts` files.
- * @param {Module} module CJS module instance
- * @param {string} filename The file path of the module
- */
-functionloadCTS(module,filename){
-constloadResult=loadSource(module,filename,'commonjs-typescript');
-module._compile(loadResult.source,filename,loadResult.format);
-}
-
-/**
- * Built-in handler for `.ts` files.
- * @param {Module} module CJS module instance
- * @param {string} filename The file path of the module
- */
-functionloadTS(module,filename){
-constpkg=packageJsonReader.getNearestParentPackageJSON(filename);
-consttypeFromPjson=pkg?.data.type;
-
-letformat;
-if(typeFromPjson==='module'){
-format='module-typescript';
-}elseif(typeFromPjson==='commonjs'){
-format='commonjs-typescript';
-}else{
-format='typescript';
-}
-constloadResult=loadSource(module,filename,format);
-
-// Function require shouldn't be used in ES modules when require(esm) is disabled.
-if(typeFromPjson==='module'&&!getOptionValue('--experimental-require-module')){
-consterr=getRequireESMError(module,pkg,loadResult.source,filename);
-throwerr;
-}
-
-module[kFormat]=loadResult.format;
-module._compile(loadResult.source,filename,loadResult.format);
-};
-
 functionreconstructErrorStack(err,parentPath,parentSource){
 consterrLine=StringPrototypeSplit(
 StringPrototypeSlice(err.stack,StringPrototypeIndexOf(
@@ -1879,6 +1788,7 @@ function getRequireESMError(mod, pkg, content, filename) {
  */
 Module._extensions['.js']=function(module,filename){
 letformat,pkg;
+consttsEnabled=getOptionValue('--experimental-strip-types');
 if(StringPrototypeEndsWith(filename,'.cjs')){
 format='commonjs';
 }elseif(StringPrototypeEndsWith(filename,'.mjs')){
@@ -1889,10 +1799,25 @@ Module._extensions['.js'] = function(module, filename) {
 if(typeFromPjson==='module'||typeFromPjson==='commonjs'||!typeFromPjson){
 format=typeFromPjson;
 }
+}elseif(StringPrototypeEndsWith(filename,'.mts')&&tsEnabled){
+format='module-typescript';
+}elseif(StringPrototypeEndsWith(filename,'.cts')&&tsEnabled){
+format='commonjs-typescript';
+}elseif(StringPrototypeEndsWith(filename,'.ts')&&tsEnabled){
+pkg=packageJsonReader.getNearestParentPackageJSON(filename);
+consttypeFromPjson=pkg?.data.type;
+if(typeFromPjson==='module'){
+format='module-typescript';
+}elseif(typeFromPjson==='commonjs'){
+format='commonjs-typescript';
+}else{
+format='typescript';
+}
 }
 const{ source,format: loadedFormat}=loadSource(module,filename,format);
 // Function require shouldn't be used in ES modules when require(esm) is disabled.
-if(loadedFormat==='module'&&!getOptionValue('--experimental-require-module')){
+if((loadedFormat==='module'||loadedFormat==='module-typescript')&&
+!getOptionValue('--experimental-require-module')){
 consterr=getRequireESMError(module,pkg,source,filename);
 throwerr;
 }