Turbopack: Use readFileSync / writeFileSync for manifest writing

timneutkens · timneutkens · commit 62d14990904d · 2025-09-11T16:29:10.000+02:00
diff --git a/packages/next/src/build/handle-entrypoints.ts b/packages/next/src/build/handle-entrypoints.ts
@@ -109,25 +109,27 @@ export async function handleRouteType({
         manifestLoader.deleteMiddlewareManifest(key)
       }
 
-      await manifestLoader.loadAppBuildManifest(page)
-      await manifestLoader.loadBuildManifest(page, 'app')
-      await manifestLoader.loadAppPathsManifest(page)
-      await manifestLoader.loadActionManifest(page)
-      await manifestLoader.loadFontManifest(page, 'app')
+      manifestLoader.loadAppBuildManifest(page)
+      manifestLoader.loadBuildManifest(page, 'app')
+      manifestLoader.loadAppPathsManifest(page)
+      manifestLoader.loadActionManifest(page)
+      manifestLoader.loadFontManifest(page, 'app')
 
       if (shouldCreateWebpackStats) {
-        await manifestLoader.loadWebpackStats(page, 'app')
+        manifestLoader.loadWebpackStats(page, 'app')
       }
 
       break
     }
     case 'app-route': {
       const key = getEntryKey('app', 'server', page)
 
-      await manifestLoader.loadAppPathsManifest(page)
+      manifestLoader.loadAppPathsManifest(page)
 
-      const middlewareManifestWritten =
-        await manifestLoader.loadMiddlewareManifest(page, 'app')
+      const middlewareManifestWritten = manifestLoader.loadMiddlewareManifest(
+        page,
+        'app'
+      )
 
       if (!middlewareManifestWritten) {
         manifestLoader.deleteMiddlewareManifest(key)
diff --git a/packages/next/src/build/turbopack-build/impl.ts b/packages/next/src/build/turbopack-build/impl.ts
@@ -202,7 +202,7 @@ export async function turbopackBuild(): Promise<{
         )),
     ])
 
-    await manifestLoader.writeManifests({
+    manifestLoader.writeManifests({
       devRewrites: undefined,
       productionRewrites: rewrites,
       entrypoints: currentEntrypoints,
diff --git a/packages/next/src/lib/fs/rename.ts b/packages/next/src/lib/fs/rename.ts
@@ -25,18 +25,18 @@ SOFTWARE.
 // This file is based on https://github.com/microsoft/vscode/blob/f860fcf11022f10a992440fd54c6e45674e39617/src/vs/base/node/pfs.ts
 // See the LICENSE at the top of the file
 
-import { rename as fsRename, stat } from 'node:fs/promises'
+import { renameSync as fsRenameSync, statSync } from 'node:fs'
 
 /**
  * A drop-in replacement for `fs.rename` that:
  * - allows to move across multiple disks
  * - attempts to retry the operation for certain error codes on Windows
  */
-export async function rename(
+export function renameSync(
   source: string,
   target: string,
   windowsRetryTimeout: number | false = 60000 /* matches graceful-fs */
-): Promise<void> {
+): void {
   if (source === target) {
     return // simulate node.js behaviour here and do a no-op if paths match
   }
@@ -46,21 +46,21 @@ export async function rename(
     // is locked by AV software. We do leverage graceful-fs to iron
     // out these issues, however in case the target file exists,
     // graceful-fs will immediately return without retry for fs.rename().
-    await renameWithRetry(source, target, Date.now(), windowsRetryTimeout)
+    renameSyncWithRetry(source, target, Date.now(), windowsRetryTimeout)
   } else {
-    await fsRename(source, target)
+    fsRenameSync(source, target)
   }
 }
 
-async function renameWithRetry(
+function renameSyncWithRetry(
   source: string,
   target: string,
   startTime: number,
   retryTimeout: number,
   attempt = 0
-): Promise<void> {
+): void {
   try {
-    return await fsRename(source, target)
+    return fsRenameSync(source, target)
   } catch (error: any) {
     if (
       error.code !== 'EACCES' &&
@@ -72,16 +72,23 @@ async function renameWithRetry(
 
     if (Date.now() - startTime >= retryTimeout) {
       console.error(
-        `[node.js fs] rename failed after ${attempt} retries with error: ${error}`
+        `Node.js fs rename failed after ${attempt} retries with error: ${error}`
       )
 
       throw error // give up after configurable timeout
     }
 
+    if (attempt > 100) {
+      console.error(
+        `Node.js fs rename failed after ${attempt} retries with error ${error}`
+      )
+      throw error
+    }
+
     if (attempt === 0) {
       let abortRetry = false
       try {
-        const statTarget = await stat(target)
+        const statTarget = statSync(target)
         if (!statTarget.isFile()) {
           abortRetry = true // if target is not a file, EPERM error may be raised and we should not attempt to retry
         }
@@ -94,13 +101,13 @@ async function renameWithRetry(
       }
     }
 
-    // Delay with incremental backoff up to 100ms
-    await timeout(Math.min(100, attempt * 10))
-
     // Attempt again
-    return renameWithRetry(source, target, startTime, retryTimeout, attempt + 1)
+    return renameSyncWithRetry(
+      source,
+      target,
+      startTime,
+      retryTimeout,
+      attempt + 1
+    )
   }
 }
-
-const timeout = (millis: number) =>
-  new Promise((resolve) => setTimeout(resolve, millis))
diff --git a/packages/next/src/lib/fs/write-atomic.ts b/packages/next/src/lib/fs/write-atomic.ts
@@ -1,17 +1,14 @@
-import { unlink, writeFile } from 'fs/promises'
-import { rename } from './rename'
+import { unlinkSync, writeFileSync } from 'fs'
+import { renameSync } from './rename'
 
-export async function writeFileAtomic(
-  filePath: string,
-  content: string
-): Promise<void> {
+export function writeFileAtomic(filePath: string, content: string): void {
   const tempPath = filePath + '.tmp.' + Math.random().toString(36).slice(2)
   try {
-    await writeFile(tempPath, content, 'utf-8')
-    await rename(tempPath, filePath)
+    writeFileSync(tempPath, content, 'utf-8')
+    renameSync(tempPath, filePath)
   } catch (e) {
     try {
-      await unlink(tempPath)
+      unlinkSync(tempPath)
     } catch {
       // ignore
     }
diff --git a/packages/next/src/server/dev/turbopack-utils.ts b/packages/next/src/server/dev/turbopack-utils.ts
@@ -243,7 +243,7 @@ export async function handleRouteType({
           await manifestLoader.loadWebpackStats(page, 'pages')
         }
 
-        await manifestLoader.writeManifests({
+        manifestLoader.writeManifests({
           devRewrites,
           productionRewrites,
           entrypoints,
@@ -334,7 +334,7 @@ export async function handleRouteType({
         manifestLoader.deleteMiddlewareManifest(key)
       }
 
-      await manifestLoader.writeManifests({
+      manifestLoader.writeManifests({
         devRewrites,
         productionRewrites,
         entrypoints,
@@ -387,17 +387,17 @@ export async function handleRouteType({
         manifestLoader.deleteMiddlewareManifest(key)
       }
 
-      await manifestLoader.loadAppBuildManifest(page)
-      await manifestLoader.loadBuildManifest(page, 'app')
-      await manifestLoader.loadAppPathsManifest(page)
-      await manifestLoader.loadActionManifest(page)
-      await manifestLoader.loadFontManifest(page, 'app')
+      manifestLoader.loadAppBuildManifest(page)
+      manifestLoader.loadBuildManifest(page, 'app')
+      manifestLoader.loadAppPathsManifest(page)
+      manifestLoader.loadActionManifest(page)
+      manifestLoader.loadFontManifest(page, 'app')
 
       if (shouldCreateWebpackStats) {
         await manifestLoader.loadWebpackStats(page, 'app')
       }
 
-      await manifestLoader.writeManifests({
+      manifestLoader.writeManifests({
         devRewrites,
         productionRewrites,
         entrypoints,
@@ -415,15 +415,15 @@ export async function handleRouteType({
 
       const type = writtenEndpoint.type
 
-      await manifestLoader.loadAppPathsManifest(page)
+      manifestLoader.loadAppPathsManifest(page)
 
       if (type === 'edge') {
         await manifestLoader.loadMiddlewareManifest(page, 'app')
       } else {
         manifestLoader.deleteMiddlewareManifest(key)
       }
 
-      await manifestLoader.writeManifests({
+      manifestLoader.writeManifests({
         devRewrites,
         productionRewrites,
         entrypoints,
@@ -690,7 +690,7 @@ export async function handleEntrypoints({
       'instrumentation',
       'instrumentation'
     )
-    await manifestLoader.writeManifests({
+    manifestLoader.writeManifests({
       devRewrites,
       productionRewrites: undefined,
       entrypoints: currentEntrypoints,
@@ -758,7 +758,7 @@ export async function handleEntrypoints({
             'middleware',
             dev.serverFields.middleware
           )
-          await manifestLoader.writeManifests({
+          manifestLoader.writeManifests({
             devRewrites,
             productionRewrites: undefined,
             entrypoints: currentEntrypoints,
@@ -956,7 +956,7 @@ export async function handlePagesErrorRoute({
   await manifestLoader.loadPagesManifest('_error')
   await manifestLoader.loadFontManifest('_error')
 
-  await manifestLoader.writeManifests({
+  manifestLoader.writeManifests({
     devRewrites,
     productionRewrites,
     entrypoints,
diff --git a/packages/next/src/shared/lib/turbopack/manifest-loader.ts b/packages/next/src/shared/lib/turbopack/manifest-loader.ts
