fix(nextjs): Make SDK multiplexer more resilient (#6905)

Author: Luca Forstner

packages/nextjs/src/config/loaders/sdkMultiplexerLoader.ts

@@ -13,7 +13,7 @@ type LoaderOptions = {
  * or edge-runtime code.
  */
 export default function sdkMultiplexerLoader(this: LoaderThis<LoaderOptions>, userCode: string): string {
-  if (!userCode.includes('__SENTRY_SDK_MULTIPLEXER__')) {
+  if (!userCode.includes('_SENTRY_SDK_MULTIPLEXER')) {
     return userCode;
   }
 

packages/nextjs/src/index.client.ts

@@ -3,4 +3,8 @@ export * from './client';
 // This file is the main entrypoint for non-Next.js build pipelines that use
 // the package.json's "browser" field or the Edge runtime (Edge API routes and middleware)
 
-// __SENTRY_SDK_MULTIPLEXER__
+/**
+ * This const serves no purpose besides being an identifier for this file that the SDK multiplexer loader can use to
+ * determine that this is in fact a file that wants to be multiplexed.
+ */
+export const _SENTRY_SDK_MULTIPLEXER = true;

packages/nextjs/src/index.server.ts

@@ -3,4 +3,8 @@ export * from './server';
 
 // This file is the main entrypoint on the server and/or when the package is `require`d
 
-// __SENTRY_SDK_MULTIPLEXER__
+/**
+ * This const serves no purpose besides being an identifier for this file that the SDK multiplexer loader can use to
+ * determine that this is in fact a file that wants to be multiplexed.
+ */
+export const _SENTRY_SDK_MULTIPLEXER = true;