From 6d401c1a4735ddaf0c7e479d64c4ae38d50105c0 Mon Sep 17 00:00:00 2001
From: Jiachi Liu <inbox@huozhi.im>
Date: Sun, 27 Aug 2023 00:55:21 +0200
Subject: [PATCH] chore: add extra error info for rsc info helper (#54609)

When I was working on #54199 , if the file path is wrong the next app build error only shows "can't read file from ...", it took me hours to figure out where it actually fails in next build command. Adding an prefix for the error message so that could identify it easier.

Also clean up other unused comments and incorrect named variables
---
 packages/next/src/build/analysis/get-page-static-info.ts | 3 ++-
 packages/next/src/build/index.ts                         | 1 -
 packages/next/src/server/lib/find-page-file.ts           | 4 ++--
 3 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/packages/next/src/build/analysis/get-page-static-info.ts b/packages/next/src/build/analysis/get-page-static-info.ts
index 6d6cc421f895..ec08c72f4a6c 100644
--- a/packages/next/src/build/analysis/get-page-static-info.ts
+++ b/packages/next/src/build/analysis/get-page-static-info.ts
@@ -286,8 +286,9 @@ async function tryToReadFile(filePath: string, shouldThrow: boolean) {
     return await fs.readFile(filePath, {
       encoding: 'utf8',
     })
-  } catch (error) {
+  } catch (error: any) {
     if (shouldThrow) {
+      error.message = `Next.js ERROR: Failed to read file ${filePath}:\n${error.message}`
       throw error
     }
   }
diff --git a/packages/next/src/build/index.ts b/packages/next/src/build/index.ts
index c0fde0830c4c..a86398b9d565 100644
--- a/packages/next/src/build/index.ts
+++ b/packages/next/src/build/index.ts
@@ -2865,7 +2865,6 @@ export default async function build(
 
           // If there's /not-found inside app, we prefer it over the pages 404
           if (hasStaticApp404) {
-            // await moveExportedPage('/_error', '/404', '/404', false, 'html')
             await moveExportedAppNotFoundTo404()
           } else {
             // Only move /404 to /404 when there is no custom 404 as in that case we don't know about the 404 page
diff --git a/packages/next/src/server/lib/find-page-file.ts b/packages/next/src/server/lib/find-page-file.ts
index b3d01383b68d..155462775ba9 100644
--- a/packages/next/src/server/lib/find-page-file.ts
+++ b/packages/next/src/server/lib/find-page-file.ts
@@ -91,7 +91,7 @@ export function createValidFileMatcher(
       pageExtensions
     )}$`
   )
-  const leafOnlyNotFoundFileRegex = new RegExp(
+  const rootNotFoundFileRegex = new RegExp(
     `^not-found\\.${getExtensionRegexString(pageExtensions)}$`
   )
   /** TODO-METADATA: support other metadata routes
@@ -136,7 +136,7 @@ export function createValidFileMatcher(
       return false
     }
     const rest = filePath.slice(appDirPath.length + 1)
-    return leafOnlyNotFoundFileRegex.test(rest)
+    return rootNotFoundFileRegex.test(rest)
   }
 
   return {