From aa2586217723ba7d30c95f78d780d9d6c9af0adf Mon Sep 17 00:00:00 2001
From: Will Binns-Smith <wbinnssmith@gmail.com>
Date: Fri, 21 Feb 2025 10:28:03 -0800
Subject: [PATCH] =?UTF-8?q?This=20uses=20`normalModule.type`=20to=20determ?=
 =?UTF-8?q?ine=20the=20source=20module=E2=80=99s=20type=20rather=20than=20?=
 =?UTF-8?q?accessing=20a=20value=20on=20`normalModule.parser`,=20which=20d?=
 =?UTF-8?q?oesn=E2=80=99t=20exist=20with=20rspack.?=
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Test Plan: CI
---
 packages/next/errors.json                      |  3 ++-
 .../loaders/next-flight-loader/index.ts        | 18 ++++++++++++++++--
 2 files changed, 18 insertions(+), 3 deletions(-)

diff --git a/packages/next/errors.json b/packages/next/errors.json
index 4d883103e3db6..26420e3ee3712 100644
--- a/packages/next/errors.json
+++ b/packages/next/errors.json
@@ -648,5 +648,6 @@
   "647": "@rspack/core is not available. Please make sure `@next/plugin-rspack` is correctly installed.",
   "648": "@rspack/plugin-react-refresh is not available. Please make sure `@next/plugin-rspack` is correctly installed.",
   "649": "Cache handlers not initialized",
-  "650": "experimental.nodeMiddleware"
+  "650": "experimental.nodeMiddleware",
+  "651": "Unexpected module type %s"
 }
diff --git a/packages/next/src/build/webpack/loaders/next-flight-loader/index.ts b/packages/next/src/build/webpack/loaders/next-flight-loader/index.ts
index e402f884c7778..f6a86b45102b5 100644
--- a/packages/next/src/build/webpack/loaders/next-flight-loader/index.ts
+++ b/packages/next/src/build/webpack/loaders/next-flight-loader/index.ts
@@ -1,4 +1,4 @@
-import type { webpack } from 'next/dist/compiled/webpack/webpack'
+import type { NormalModule, webpack } from 'next/dist/compiled/webpack/webpack'
 import { RSC_MOD_REF_PROXY_ALIAS } from '../../../../lib/constants'
 import {
   BARREL_OPTIMIZATION_PREFIX,
@@ -97,7 +97,7 @@ export default function transformSource(
   if (buildInfo.rsc?.type === RSC_MODULE_TYPES.client) {
     const assumedSourceType = getAssumedSourceType(
       module,
-      (module.parser as javascript.JavascriptParser).sourceType
+      sourceTypeFromModule(module)
     )
 
     const clientRefs = buildInfo.rsc.clientRefs!
@@ -171,3 +171,17 @@ module.exports = createProxy(${stringifiedResourceKey})
   )
   this.callback(null, replacedSource, sourceMap)
 }
+
+function sourceTypeFromModule(module: NormalModule): SourceType {
+  const moduleType = module.type
+  switch (moduleType) {
+    case 'javascript/auto':
+      return 'auto'
+    case 'javascript/dynamic':
+      return 'script'
+    case 'javascript/esm':
+      return 'module'
+    default:
+      throw new Error('Unexpected module type ' + moduleType)
+  }
+}