fix(nextjs): safely detect Turbopack in Edge/Browser environments

Author: asionesjia

packages/nextjs/src/client/index.ts

@@ -78,7 +78,7 @@ export function init(options: BrowserOptions): Client | undefined {
   }
 
   try {
-    if (isTurbopack) {
+    if (isTurbopack()) {
       getGlobalScope().setTag('turbopack', true);
     }
   } catch {

packages/nextjs/src/common/utils/isTurbopack.ts

@@ -1 +1,8 @@
-export const isTurbopack = process.env.TURBOPACK === '1' || (typeof process !== 'undefined' && 'turbopack' in process && process.turbopack);
+/**
+ * Detect whether running under Turbopack
+ */
+export function isTurbopack(): boolean {
+  if (typeof process === 'undefined') return false;
+  // eslint-disable-next-line @typescript-eslint/no-unsafe-member-access
+  return process.env?.TURBOPACK === '1' || !!(process as any)?.turbopack;
+}

packages/nextjs/src/edge/index.ts

@@ -96,7 +96,7 @@ export function init(options: VercelEdgeOptions = {}): void {
   });
 
   try {
-    if (isTurbopack) {
+    if (isTurbopack()) {
       getGlobalScope().setTag('turbopack', true);
     }
   } catch {

packages/nextjs/src/server/index.ts

@@ -369,7 +369,7 @@ export function init(options: NodeOptions): NodeClient | undefined {
   }
 
   try {
-    if (isTurbopack) {
+    if (isTurbopack()) {
       getGlobalScope().setTag('turbopack', true);
     }
   } catch {