Repository: vercel/next.js
Pull request: fix: Rspack dev gets stuck after removing a page

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Rspack's incremental build algorithm causes a situation where deleted entries in dynamic entries still get built.

If a page is deleted, an infinite loop occurs in the corresponding `next-app-loader`, causing the entire compilation to hang.

The root cause of the hang lies in `const resolvedPagePath = await resolver(matchedPagePath)` failing to resolve `resolvedPagePath`, preventing the loop from exiting.

When `resolvedPagePath` doesn't exist, we should immediately throw an Error. This logic would also benefit webpack, as scenarios where pages are deleted during the execution of `next-app-loader` do occur.




Changed files:
filename: packages/next/errors.json
patch: @@ -708,5 +708,6 @@
   "707": "Invariant app-page handler received invalid cache entry %s",
   "708": "Failed to persist Chrome DevTools workspace UUID. The Chrome DevTools Workspace needs to be reconnected after the next page reload.",
   "709": "`rspack.getModuleNamedExports` is not supported by the wasm bindings.",
-  "710": "Unable to remove an invalidated webpack cache. If this issue persists you can work around it by deleting %s"
+  "710": "Unable to remove an invalidated webpack cache. If this issue persists you can work around it by deleting %s",
+  "711": "Can't resolve %s"
 }

filename: packages/next/src/build/webpack/loaders/next-app-loader/index.ts
patch: @@ -251,6 +251,8 @@ async function createTreeCodeFromPath(
           ${createMetadataExportsCode(metadata)}
         }]`
           continue
+        } else {
+          throw new Error(`Can't resolve ${matchedPagePath}`)
         }
       }