refactor(i18n): extract loadLanguage into testable module

Move loadLanguage from inline in main.tsx to a separate loadLanguage.ts module.
Test imports the actual production code instead of duplicating logic.

Co-authored-by: hotlong <50353452+hotlong@users.noreply.github.com>
Agent-Logs-Url: https://github.com/objectstack-ai/objectui/sessions/c9dec823-2a7f-43fa-a55e-6b357fefe3d5

Author: Copilot

apps/console/src/__tests__/LoadLanguage.test.tsx

@@ -7,29 +7,7 @@
  */
 
 import { describe, it, expect, vi, beforeEach, afterEach } from 'vitest';
-
-// ---------------------------------------------------------------------------
-// Re-implement the loadLanguage logic under test (mirrors apps/console/src/main.tsx)
-// ---------------------------------------------------------------------------
-async function loadLanguage(lang: string): Promise<Record<string, unknown>> {
-  try {
-    const res = await fetch(`/api/v1/i18n/translations/${lang}`);
-    if (!res.ok) {
-      console.warn(`[i18n] Failed to load translations for '${lang}': HTTP ${res.status}`);
-      return {};
-    }
-    const json = await res.json();
-    // Unwrap the spec REST API envelope when present
-    if (json && typeof json === 'object' && json.data && json.data.translations && typeof json.data.translations === 'object') {
-      return json.data.translations as Record<string, unknown>;
-    }
-    // Fallback: mock server / local dev returns flat translation objects
-    return json;
-  } catch (err) {
-    console.warn(`[i18n] Failed to load translations for '${lang}':`, err);
-    return {};
-  }
-}
+import { loadLanguage } from '../loadLanguage';
 
 // ---------------------------------------------------------------------------
 // Tests

apps/console/src/loadLanguage.ts

@@ -0,0 +1,27 @@
+/**
+ * Load application-specific translations for a given language from the API.
+ *
+ * The @objectstack/spec REST API (`/api/v1/i18n/translations/:locale`) wraps
+ * its response in the standard envelope: `{ data: { locale, translations } }`.
+ * We extract `data.translations` when present, and fall back to the raw JSON
+ * for mock / local-dev environments that may return flat translation objects.
+ */
+export async function loadLanguage(lang: string): Promise<Record<string, unknown>> {
+  try {
+    const res = await fetch(`/api/v1/i18n/translations/${lang}`);
+    if (!res.ok) {
+      console.warn(`[i18n] Failed to load translations for '${lang}': HTTP ${res.status}`);
+      return {};
+    }
+    const json = await res.json();
+    // Unwrap the spec REST API envelope when present
+    if (json && typeof json === 'object' && json.data && json.data.translations && typeof json.data.translations === 'object') {
+      return json.data.translations as Record<string, unknown>;
+    }
+    // Fallback: mock server / local dev returns flat translation objects
+    return json;
+  } catch (err) {
+    console.warn(`[i18n] Failed to load translations for '${lang}':`, err);
+    return {};
+  }
+}

apps/console/src/main.tsx

@@ -10,6 +10,7 @@ import './index.css';
 import { App } from './App';
 import { I18nProvider } from '@object-ui/i18n';
 import { MobileProvider } from '@object-ui/mobile';
+import { loadLanguage } from './loadLanguage';
 
 // Register plugins (side-effect imports for ComponentRegistry)
 import '@object-ui/plugin-grid';
@@ -27,34 +28,6 @@ import '@object-ui/plugin-dashboard';
 import '@object-ui/plugin-report';
 import '@object-ui/plugin-markdown';
 
-/**
- * Load application-specific translations for a given language from the API.
- *
- * The @objectstack/spec REST API (`/api/v1/i18n/translations/:locale`) wraps
- * its response in the standard envelope: `{ data: { locale, translations } }`.
- * We extract `data.translations` when present, and fall back to the raw JSON
- * for mock / local-dev environments that may return flat translation objects.
- */
-async function loadLanguage(lang: string): Promise<Record<string, unknown>> {
-  try {
-    const res = await fetch(`/api/v1/i18n/translations/${lang}`);
-    if (!res.ok) {
-      console.warn(`[i18n] Failed to load translations for '${lang}': HTTP ${res.status}`);
-      return {};
-    }
-    const json = await res.json();
-    // Unwrap the spec REST API envelope when present
-    if (json && typeof json === 'object' && json.data && json.data.translations && typeof json.data.translations === 'object') {
-      return json.data.translations as Record<string, unknown>;
-    }
-    // Fallback: mock server / local dev returns flat translation objects
-    return json;
-  } catch (err) {
-    console.warn(`[i18n] Failed to load translations for '${lang}':`, err);
-    return {};
-  }
-}
-
 // Start MSW before rendering the app
 async function bootstrap() {
   // Initialize Mock Service Worker if enabled (lazy-loaded to keep production bundle lean)