1 files changed, 58 insertions, 4 deletions
diff --git a/lib/internal/modules/cjs/helpers.js b/lib/internal/modules/cjs/helpers.js
index 71abcbf880..5e0e1b06ae 100644
--- a/lib/internal/modules/cjs/helpers.js
+++ b/lib/internal/modules/cjs/helpers.js
@@ -1,19 +1,72 @@
 'use strict';
 
 const { Object } = primordials;
+const {
+  ERR_MANIFEST_DEPENDENCY_MISSING,
+  ERR_UNKNOWN_BUILTIN_MODULE
+} = require('internal/errors').codes;
+const { NativeModule } = require('internal/bootstrap/loaders');
+const { getOptionValue } = require('internal/options');
+const experimentalModules = getOptionValue('--experimental-modules');
 
 const { validateString } = require('internal/validators');
 const path = require('path');
-const { pathToFileURL } = require('internal/url');
+const { pathToFileURL, fileURLToPath } = require('internal/url');
 const { URL } = require('url');
 
+const debug = require('internal/util/debuglog').debuglog('module');
+
+function loadNativeModule(filename, request, experimentalModules) {
+  const mod = NativeModule.map.get(filename);
+  if (mod) {
+    debug('load native module %s', request);
+    mod.compileForPublicLoader(experimentalModules);
+    return mod;
+  }
+}
+
 // Invoke with makeRequireFunction(module) where |module| is the Module object
 // to use as the context for the require() function.
-function makeRequireFunction(mod) {
+// Use redirects to set up a mapping from a policy and restrict dependencies
+function makeRequireFunction(mod, redirects) {
   const Module = mod.constructor;
 
-  function require(path) {
-    return mod.require(path);
+  let require;
+  if (redirects) {
+    const { map, reaction } = redirects;
+    const id = mod.filename || mod.id;
+    require = function require(path) {
+      let missing = true;
+      if (map === true) {
+        missing = false;
+      } else if (map.has(path)) {
+        const redirect = map.get(path);
+        if (redirect === true) {
+          missing = false;
+        } else if (typeof redirect === 'string') {
+          const parsed = new URL(redirect);
+          if (parsed.protocol === 'node:') {
+            const specifier = parsed.pathname;
+            const mod = loadNativeModule(
+              specifier,
+              redirect,
+              experimentalModules);
+            if (mod && mod.canBeRequiredByUsers) return mod.exports;
+            throw new ERR_UNKNOWN_BUILTIN_MODULE(specifier);
+          } else if (parsed.protocol === 'file:') {
+            return mod.require(fileURLToPath(parsed));
+          }
+        }
+      }
+      if (missing) {
+        reaction(new ERR_MANIFEST_DEPENDENCY_MISSING(id, path));
+      }
+      return mod.require(path);
+    };
+  } else {
+    require = function require(path) {
+      return mod.require(path);
+    };
   }
 
   function resolve(request, options) {
@@ -114,6 +167,7 @@ function normalizeReferrerURL(referrer) {
 module.exports = {
   addBuiltinLibsToObject,
   builtinLibs,
+  loadNativeModule,
   makeRequireFunction,
   normalizeReferrerURL,
   stripBOM,