From 65dea127f95ddde9ec7f36d2ac576dc7916ef2ff Mon Sep 17 00:00:00 2001
From: John Costa <costajohnt@gmail.com>
Date: Thu, 29 Oct 2026 10:20:15 -0700
Subject: [PATCH] fix(optimize-locales-plugin): type Turbopack loader locales
 as a mutable array

Next's TurbopackLoaderOptions only accepts mutable JSONValue arrays, so the
readonly locales type made optimizeLocales.turbopack() rules fail to
type-check in a NextConfig.
---
 packages/dev/optimize-locales-plugin/LocalesPlugin.d.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/dev/optimize-locales-plugin/LocalesPlugin.d.ts b/packages/dev/optimize-locales-plugin/LocalesPlugin.d.ts
index 733429f4d86..f7d23082b0c 100644
--- a/packages/dev/optimize-locales-plugin/LocalesPlugin.d.ts
+++ b/packages/dev/optimize-locales-plugin/LocalesPlugin.d.ts
@@ -25,7 +25,7 @@ type TurbopackOptionsList = readonly [TurbopackOptions, ...TurbopackOptions[]];
 
 type TurbopackRule = {
   condition?: TurbopackCondition;
-  loaders: [{loader: string; options: {locales: readonly string[]}}];
+  loaders: [{loader: string; options: {locales: string[]}}];
   as: '*.js';
 };