use deep clone

huozhi · huozhi · commit 17ffc7b2ac70 · 2025-06-17T16:35:42.000+02:00
diff --git a/packages/next/src/server/config.ts b/packages/next/src/server/config.ts
@@ -1268,12 +1268,9 @@ export default async function loadConfig(
     }
 
     // Clone a new userConfig each time to avoid mutating the original
-    const userConfig = {
-      ...(await normalizeConfig(
-        phase,
-        userConfigModule.default || userConfigModule
-      )),
-    } as NextConfig
+    const userConfig = cloneObject(
+      await normalizeConfig(phase, userConfigModule.default || userConfigModule)
+    ) as NextConfig
 
     if (!process.env.NEXT_MINIMAL) {
       // We only validate the config against schema in non minimal mode
@@ -1479,3 +1476,22 @@ export function getConfiguredExperimentalFeatures(
   }
   return configuredExperimentalFeatures
 }
+
+function cloneObject(obj: any): any {
+  if (obj === null || typeof obj !== 'object') {
+    return obj
+  }
+
+  if (Array.isArray(obj)) {
+    return obj.map(cloneObject)
+  }
+  const keys = Object.keys(obj)
+  if (keys.length === 0) {
+    return obj
+  }
+
+  return keys.reduce((acc, key) => {
+    ;(acc as any)[key] = cloneObject(obj[key])
+    return acc
+  }, {})
+}
