module: disable cjs snapshotting into esm loader

PR-URL: #34467
Reviewed-By: Bradley Farias <[email protected]>
Reviewed-By: Geoffrey Booth <[email protected]>

Author: guybedford

lib/internal/modules/cjs/loader.js

@@ -32,7 +32,6 @@ const {
   ArrayPrototypeJoin,
   Error,
   JSONParse,
-  Map,
   Number,
   ObjectCreate,
   ObjectDefineProperty,
@@ -113,8 +112,6 @@ const {
 } = require('internal/util/types');
 
 const asyncESM = require('internal/process/esm_loader');
-const ModuleJob = require('internal/modules/esm/module_job');
-const { ModuleWrap, kInstantiated } = internalBinding('module_wrap');
 const {
   encodedSepRegEx,
   packageInternalResolve
@@ -374,7 +371,7 @@ function tryPackage(requestPath, exts, isMain, originalPath) {
 // In order to minimize unnecessary lstat() calls,
 // this cache is a list of known-real paths.
 // Set to an empty Map to reset.
-const realpathCache = new Map();
+const realpathCache = new SafeMap();
 
 // Check if the file exists and is not a directory
 // if using --preserve-symlinks and isMain is false,
@@ -1118,31 +1115,6 @@ Module.prototype.load = function(filename) {
   }
   Module._extensions[extension](this, filename);
   this.loaded = true;
-
-  const ESMLoader = asyncESM.ESMLoader;
-  const url = `${pathToFileURL(filename)}`;
-  const module = ESMLoader.moduleMap.get(url);
-  // Create module entry at load time to snapshot exports correctly
-  const exports = this.exports;
-  // Called from cjs translator
-  if (module !== undefined && module.module !== undefined) {
-    if (module.module.getStatus() >= kInstantiated)
-      module.module.setExport('default', exports);
-  } else {
-    // Preemptively cache
-    // We use a function to defer promise creation for async hooks.
-    ESMLoader.moduleMap.set(
-      url,
-      // Module job creation will start promises.
-      // We make it a function to lazily trigger those promises
-      // for async hooks compatibility.
-      () => new ModuleJob(ESMLoader, url, () =>
-        new ModuleWrap(url, undefined, ['default'], function() {
-          this.setExport('default', exports);
-        })
-      , false /* isMain */, false /* inspectBrk */)
-    );
-  }
 };
 
 
@@ -1262,7 +1234,7 @@ Module.prototype._compile = function(content, filename) {
   const exports = this.exports;
   const thisValue = exports;
   const module = this;
-  if (requireDepth === 0) statCache = new Map();
+  if (requireDepth === 0) statCache = new SafeMap();
   if (inspectorWrapper) {
     result = inspectorWrapper(compiledWrapper, thisValue, exports,
                               require, module, filename, dirname);

lib/internal/modules/esm/loader.js

@@ -5,8 +5,7 @@ require('internal/modules/cjs/loader');
 
 const {
   FunctionPrototypeBind,
-  ObjectSetPrototypeOf,
-  SafeMap,
+  ObjectSetPrototypeOf
 } = primordials;
 
 const {
@@ -46,9 +45,6 @@ class Loader {
     // Registry of loaded modules, akin to `require.cache`
     this.moduleMap = new ModuleMap();
 
-    // Map of already-loaded CJS modules to use
-    this.cjsCache = new SafeMap();
-
     // This hook is called before the first root module is imported. It's a
     // function that returns a piece of code that runs as a sloppy-mode script.
     // The script may evaluate to a function that can be called with a

lib/internal/modules/esm/translators.js

@@ -11,6 +11,8 @@ const {
   StringPrototypeReplace,
 } = primordials;
 
+const assert = require('internal/assert');
+
 let _TYPES = null;
 function lazyTypes() {
   if (_TYPES !== null) return _TYPES;
@@ -132,27 +134,21 @@ const isWindows = process.platform === 'win32';
 const winSepRegEx = /\//g;
 translators.set('commonjs', function commonjsStrategy(url, isMain) {
   debug(`Translating CJSModule ${url}`);
-  const pathname = internalURLModule.fileURLToPath(new URL(url));
-  const cached = this.cjsCache.get(url);
-  if (cached) {
-    this.cjsCache.delete(url);
-    return cached;
-  }
-  const module = CJSModule._cache[
-    isWindows ? StringPrototypeReplace(pathname, winSepRegEx, '\\') : pathname
-  ];
-  if (module && module.loaded) {
-    const exports = module.exports;
-    return new ModuleWrap(url, undefined, ['default'], function() {
-      this.setExport('default', exports);
-    });
-  }
+  let filename = internalURLModule.fileURLToPath(new URL(url));
+  if (isWindows)
+    filename = StringPrototypeReplace(filename, winSepRegEx, '\\');
   return new ModuleWrap(url, undefined, ['default'], function() {
     debug(`Loading CJSModule ${url}`);
-    // We don't care about the return val of _load here because Module#load
-    // will handle it for us by checking the loader registry and filling the
-    // exports like above
-    CJSModule._load(pathname, undefined, isMain);
+    let module = CJSModule._cache[filename];
+    if (!module || !module.loaded) {
+      module = new CJSModule(filename);
+      module.filename = filename;
+      module.paths = CJSModule._nodeModulePaths(module.path);
+      CJSModule._cache[filename] = module;
+      module.load(filename);
+      assert(module && module.loaded);
+    }
+    this.setExport('default', module.exports);
   });
 });
 

test/es-module/test-esm-snapshot.mjs

@@ -3,4 +3,4 @@ import '../fixtures/es-modules/esm-snapshot-mutator.js';
 import one from '../fixtures/es-modules/esm-snapshot.js';
 import assert from 'assert';
 
-assert.strictEqual(one, 1);
+assert.strictEqual(one, 2);