Merge pull request 'Language switch button unit test' (#108) from testing/language-switch into main

Reviewed-on: #108
Reviewed-by: Jakob Scheid

package.json

@@ -17,6 +17,7 @@
     "vue-router": "^5.0.6"
   },
   "devDependencies": {
+    "@vue/test-utils": "^2.4.6",
     "@vitejs/plugin-vue": "^6.0.6",
     "jsdom": "^29.1.1",
     "vite": "^8.0.10",

src/features/i18n/components/__tests__/LanguageSwitchButton.test.js

@@ -0,0 +1,114 @@
+/*
+Copyright 2026 Seekra
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+import { expect, test, describe, vi, beforeEach } from 'vitest';
+import { mount } from '@vue/test-utils';
+import LanguageSwitchButton from '../LanguageSwitchButton.vue';
+import { loadLanguage } from '@/i18n';
+
+vi.mock('@/i18n', () => ({
+    loadLanguage: vi.fn(() => Promise.resolve()),
+    LANGUAGES_RTL: ['ar', 'he'],
+    SUPPORTED_LANGUAGES: ['en', 'de', 'ar']
+}));
+
+vi.mock('vue-i18n', () => ({
+    useI18n: () => ({
+        t: (key) => key,
+        locale: { value: 'de' }
+    })
+}));
+
+vi.mock('@/features/icons/components/Icon.vue', () => ({
+    default: {
+        name: 'Icon',
+        template: '<span>Icon</span>'
+    }
+}));
+
+describe('LanguageSwitchButton.vue', () => {
+    beforeEach(() => {
+        vi.clearAllMocks();
+        localStorage.clear();
+        document.documentElement.lang = '';
+        document.documentElement.dir = '';
+    });
+
+    test('renders correctly with initial state closed', () => {
+        const wrapper = mount(LanguageSwitchButton);
+        
+        expect(wrapper.find('.language-button').exists()).toBe(true);
+        expect(wrapper.find('.language-dropdown').exists()).toBe(false);
+        expect(wrapper.find('.language-button').attributes('aria-expanded')).toBe('false');
+    });
+
+    test('opens the dropdown when language button is clicked', async () => {
+        const wrapper = mount(LanguageSwitchButton);
+        const button = wrapper.find('.language-button');
+        
+        await button.trigger('click');
+        
+        expect(wrapper.find('.language-dropdown').exists()).toBe(true);
+        expect(button.attributes('aria-expanded')).toBe('true');
+    });
+
+    const languageTestCases = [
+        { code: 'en', expectedDir: 'ltr' },
+        { code: 'de', expectedDir: 'ltr' },
+        { code: 'ar', expectedDir: 'rtl' }
+    ];
+
+    test.for(languageTestCases)('selectLanguage($code) sets localStorage, html attributes and changes layout direction to $expectedDir', async ({ code, expectedDir }) => {
+        const wrapper = mount(LanguageSwitchButton);
+        
+        await wrapper.find('.language-button').trigger('click');
+        
+        const options = wrapper.findAll('.language-dropdown li');
+        const optionToClick = options.find(opt => opt.text().includes(code));
+        
+        await optionToClick.trigger('click');
+
+        expect(loadLanguage).toHaveBeenCalledWith(code);
+        expect(localStorage.getItem('locale')).toBe(code);
+        expect(document.documentElement.lang).toBe(code);
+        expect(document.documentElement.dir).toBe(expectedDir);
+        expect(wrapper.find('.language-dropdown').exists()).toBe(false);
+    });
+
+    test('closes the dropdown when clicking outside the component', async () => {
+        const wrapper = mount(LanguageSwitchButton, {
+            attachTo: document.body
+        });
+
+        await wrapper.find('.language-button').trigger('click');
+        expect(wrapper.find('.language-dropdown').exists()).toBe(true);
+
+        await new Promise(resolve => setTimeout(resolve, 0));
+
+        const externalDiv = document.createElement('div');
+        document.body.appendChild(externalDiv);
+        
+        const clickEvent = new MouseEvent('click', { bubbles: true });
+        externalDiv.dispatchEvent(clickEvent);
+        
+        await wrapper.vm.$nextTick();
+
+        expect(wrapper.find('.language-dropdown').exists()).toBe(false);
+
+        wrapper.unmount();
+        externalDiv.remove();
+    });
+});