From 07669cf917a33a842152207e048b7b3ab018cf2f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Wojciech=20Tyczy=C5=84ski?= <tykus160@gmail.com>
Date: Thu, 23 Apr 2026 11:20:10 +0200
Subject: [PATCH] test: Fix `customTrackLabel` tests (#10026)

Provide consistent system language code in tests to avoid potential
failures on different systems.
---
 test/ui/ui_integration.js | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/test/ui/ui_integration.js b/test/ui/ui_integration.js
index ac7a20982..b90962683 100644
--- a/test/ui/ui_integration.js
+++ b/test/ui/ui_integration.js
@@ -29,8 +29,18 @@ describe('UI', () => {
   let controls;
   /** @type {shakaNamespaceType} */
   let compiledShaka;
+  /** @type {!Array<string>|undefined} */
+  let savedLanguages;
 
   beforeAll(async () => {
+    // Force locale to en-US so that localized strings
+    // (e.g. "Unrecognized") are predictable across machines.
+    savedLanguages = navigator.languages;
+    Object.defineProperty(navigator, 'languages', {
+      get: () => ['en-US'],
+      configurable: true,
+    });
+
     cssLink = /** @type {!HTMLLinkElement} */(document.createElement('link'));
     await UiUtils.setupCSS(cssLink);
 
@@ -124,6 +134,12 @@ describe('UI', () => {
 
   afterAll(() => {
     document.head.removeChild(cssLink);
+
+    // Restore the original navigator.languages.
+    Object.defineProperty(navigator, 'languages', {
+      get: () => savedLanguages,
+      configurable: true,
+    });
   });
 
   describe('language selections', () => {