From a7f7f3d3756e21ed13bba86e30c0f707c4a0fa8e Mon Sep 17 00:00:00 2001
From: domu1de <dev@domu1.de>
Date: Thu, 24 Jul 2025 11:17:49 +0200
Subject: [PATCH] Fix mutability issue when registering rules with multiple
 language keys

---
 packages/typir/src/utils/rule-registration.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/typir/src/utils/rule-registration.ts b/packages/typir/src/utils/rule-registration.ts
index 54137901..69d11f96 100644
--- a/packages/typir/src/utils/rule-registration.ts
+++ b/packages/typir/src/utils/rule-registration.ts
@@ -103,7 +103,7 @@ export class RuleRegistry<RuleType, LanguageType> implements TypeGraphListener {
     addRule(rule: RuleType, givenOptions?: Partial<RuleOptions>): void {
         const newOptions = this.getRuleOptions(givenOptions);
         const languageKeyUndefined: boolean = newOptions.languageKey === undefined;
-        const languageKeys: string[] = toArray(newOptions.languageKey);
+        const languageKeys: string[] = toArray(newOptions.languageKey, { newArray: true });
 
         const existingOptions = this.ruleToOptions.get(rule);
         const diffOptions: RuleOptions = {