fix: load i18n in tests without typescript error

.github/workflows/pr_ci_frontend.yaml

@@ -53,4 +53,4 @@ jobs:
       - name: Run Vitest - Component Testing
         if: always()
         working-directory: ./frontend
-        run: sudo yarn test
+        run: sudo yarn test --silent

CONTRIBUTING.md

@@ -408,8 +408,10 @@ We use [Vitest](https://vitest.dev/) for component and unit testing.  You can ru
 
 ```bash
 # Within ./frontend:
-yarn test
+yarn test --silent
 ```
+> [!NOTE]
+> The `--silent` flag is to suppress a lot of warnings from existing issues between Nuxt and Vitest.  If you need to see the warnings omit the `--silent` flag.
 
 Please see the [frontend testing guide](FRONTEND_TESTING.md) for information on how to write component tests.
 

frontend/test/setup.ts

@@ -1,7 +1,9 @@
 // SPDX-License-Identifier: AGPL-3.0-or-later
-import { useNuxtApp } from "#app";
 import { config } from "@vue/test-utils";
 import { createPinia, defineStore, setActivePinia } from "pinia";
+import { createI18n } from "vue-i18n";
+import en from "~/i18n/en-US.json" assert { type: "json" };
+
 import type { UseColorModeFn } from "~/test/vitest-globals";
 
 // Set up Pinia.
@@ -19,20 +21,16 @@ const useColorModeFn: UseColorModeFn = () => ({
 globalThis.useColorModeMock = vi.fn(useColorModeFn);
 
 // Set up I18n.
-beforeAll(() => {
-  // https://github.com/nuxt/test-utils/issues/566
-  const nuxtApp = useNuxtApp();
-
-  config.global.plugins.push({
-    async install(app, ...options) {
-      // @ts-expect-error Typescript cannot detect Nuxt plugins.
-      const i18n = nuxtApp.vueApp.__VUE_I18N__;
-
-      await i18n.install(app, ...options);
-    },
-  });
+// https://github.com/nuxt-modules/i18n/issues/2637#issuecomment-2233566361
+const i18n = createI18n({
+  legacy: false,
+  locale: "en",
+  fallbackLocale: "en",
+  messages: Object.assign({ en }),
 });
 
+config.global.plugins.push(i18n);
+
 afterEach(() => {
   // Clean up Pinia.
   setActivePinia(createPinia());