vm: add support for import.meta to Module

Fixes: https://github.com/nodejs/node/issues/18570

PR-URL: https://github.com/nodejs/node/pull/19277
Reviewed-By: Gus Caplan <me@gus.host>
Reviewed-By: Tiancheng "Timothy" Gu <timothygu99@gmail.com>

3 files changed, 41 insertions, 6 deletions

diff --git a/lib/internal/bootstrap/node.js b/lib/internal/bootstrap/node.js
index 01efe6f329..99bf00a6d6 100644
--- a/lib/internal/bootstrap/node.js
+++ b/lib/internal/bootstrap/node.js
@@ -108,10 +108,13 @@
         'DeprecationWarning', 'DEP0062', startup, true);
     }
 
-    if (process.binding('config').experimentalModules) {
-      process.emitWarning(
-        'The ESM module loader is experimental.',
-        'ExperimentalWarning', undefined);
+    if (process.binding('config').experimentalModules ||
+        process.binding('config').experimentalVMModules) {
+      if (process.binding('config').experimentalModules) {
+        process.emitWarning(
+          'The ESM module loader is experimental.',
+          'ExperimentalWarning', undefined);
+      }
       NativeModule.require('internal/process/esm_loader').setup();
     }
 
diff --git a/lib/internal/process/esm_loader.js b/lib/internal/process/esm_loader.js
index bcb6501af6..db28ca04b1 100644
--- a/lib/internal/process/esm_loader.js
+++ b/lib/internal/process/esm_loader.js
@@ -10,6 +10,10 @@ const { getURLFromFilePath } = require('internal/url');
 const Loader = require('internal/modules/esm/loader');
 const path = require('path');
 const { URL } = require('url');
+const {
+  initImportMetaMap,
+  wrapToModuleMap
+} = require('internal/vm/module');
 
 function normalizeReferrerURL(referrer) {
   if (typeof referrer === 'string' && path.isAbsolute(referrer)) {
@@ -19,7 +23,18 @@ function normalizeReferrerURL(referrer) {
 }
 
 function initializeImportMetaObject(wrap, meta) {
-  meta.url = wrap.url;
+  const vmModule = wrapToModuleMap.get(wrap);
+  if (vmModule === undefined) {
+    // This ModuleWrap belongs to the Loader.
+    meta.url = wrap.url;
+  } else {
+    const initializeImportMeta = initImportMetaMap.get(vmModule);
+    if (initializeImportMeta !== undefined) {
+      // This ModuleWrap belongs to vm.Module, initializer callback was
+      // provided.
+      initializeImportMeta(meta, vmModule);
+    }
+  }
 }
 
 let loaderResolve;
diff --git a/lib/internal/vm/module.js b/lib/internal/vm/module.js
index 48d591f3bf..9af071ce28 100644
--- a/lib/internal/vm/module.js
+++ b/lib/internal/vm/module.js
@@ -43,6 +43,10 @@ const perContextModuleId = new WeakMap();
 const wrapMap = new WeakMap();
 const dependencyCacheMap = new WeakMap();
 const linkingStatusMap = new WeakMap();
+// vm.Module -> function
+const initImportMetaMap = new WeakMap();
+// ModuleWrap -> vm.Module
+const wrapToModuleMap = new WeakMap();
 
 class Module {
   constructor(src, options = {}) {
@@ -80,6 +84,16 @@ class Module {
       perContextModuleId.set(context, 1);
     }
 
+    if (options.initializeImportMeta !== undefined) {
+      if (typeof options.initializeImportMeta === 'function') {
+        initImportMetaMap.set(this, options.initializeImportMeta);
+      } else {
+        throw new ERR_INVALID_ARG_TYPE(
+          'options.initializeImportMeta', 'function',
+          options.initializeImportMeta);
+      }
+    }
+
     const wrap = new ModuleWrap(src, url, {
       [kParsingContext]: context,
       lineOffset: options.lineOffset,
@@ -88,6 +102,7 @@ class Module {
 
     wrapMap.set(this, wrap);
     linkingStatusMap.set(this, 'unlinked');
+    wrapToModuleMap.set(wrap, this);
 
     Object.defineProperties(this, {
       url: { value: url, enumerable: true },
@@ -206,5 +221,7 @@ class Module {
 }
 
 module.exports = {
-  Module
+  Module,
+  initImportMetaMap,
+  wrapToModuleMap
 };