1 files changed, 6 insertions, 2 deletions
diff --git a/lib/internal/main/worker_thread.js b/lib/internal/main/worker_thread.js
index 7cf8ffb8b4..13d7e8de0e 100644
--- a/lib/internal/main/worker_thread.js
+++ b/lib/internal/main/worker_thread.js
@@ -108,6 +108,9 @@ port.on('message', (message) => {
     initializeDeprecations();
     initializeCJSLoader();
     initializeESMLoader();
+
+    const CJSLoader = require('internal/modules/cjs/loader');
+    assert(!CJSLoader.hasLoadedAnyUserCJSModule);
     loadPreloadModules();
     initializeFrozenIntrinsics();
     publicWorker.parentPort = publicPort;
@@ -141,8 +144,9 @@ port.on('message', (message) => {
       evalScript('[worker eval]', filename);
     } else {
       // script filename
-      const CJSModule = require('internal/modules/cjs/loader').Module;
-      CJSModule.runMain(process.argv[1] = filename);
+      // runMain here might be monkey-patched by users in --require.
+      // XXX: the monkey-patchability here should probably be deprecated.
+      CJSLoader.Module.runMain(process.argv[1] = filename);
     }
   } else if (message.type === STDIO_PAYLOAD) {
     const { stream, chunk, encoding } = message;