avoid errors if "track-module-loading" ends up in an edge module

lubieowoce · lubieowoce · commit 406ccfdcb1f3 · 2025-05-16T19:51:50.000+02:00
diff --git a/packages/next/src/server/app-render/module-loading/track-module-loading.instance.ts b/packages/next/src/server/app-render/module-loading/track-module-loading.instance.ts
@@ -1,14 +1,26 @@
 import { CacheSignal } from '../cache-signal'
 import { isThenable } from '../../../shared/lib/is-thenable'
 
-/** Tracks all in-flight async imports and chunk loads. */
-const moduleLoadingSignal = new CacheSignal()
+/**
+ * Tracks all in-flight async imports and chunk loads.
+ * Initialized lazily, because we don't want this to error in case it gets pulled into an edge runtime module.
+ */
+let _moduleLoadingSignal: CacheSignal | null
+function getModuleLoadingSignal() {
+  if (!_moduleLoadingSignal) {
+    _moduleLoadingSignal = new CacheSignal()
+  }
+  return _moduleLoadingSignal
+}
 
 export function trackPendingChunkLoad(promise: Promise<unknown>) {
+  const moduleLoadingSignal = getModuleLoadingSignal()
   moduleLoadingSignal.trackRead(promise)
 }
 
 export function trackPendingImport(exportsOrPromise: unknown) {
+  const moduleLoadingSignal = getModuleLoadingSignal()
+
   // requiring an async module returns a promise.
   // if it's sync, there's nothing to track.
   if (isThenable(exportsOrPromise)) {
@@ -28,6 +40,8 @@ export function trackPendingImport(exportsOrPromise: unknown) {
  * So if we see one, we want to extend the duration of `cacheSignal` at least until the import/chunk-load is done.
  */
 export function trackPendingModules(cacheSignal: CacheSignal): void {
+  const moduleLoadingSignal = getModuleLoadingSignal()
+
   // We can't just use `cacheSignal.trackRead(moduleLoadingSignal.cacheReady())`,
   // because we might start and finish multiple batches of module loads while waiting for caches,
   // and `moduleLoadingSignal.cacheReady()` would resolve after the first batch.
