MOBILE-4288 multilang: Use parent languages

src/addons/filter/multilang/services/handlers/multilang.ts

@@ -44,27 +44,34 @@ export class AddonFilterMultilangHandlerService extends CoreFilterDefaultHandler
         options?: CoreFilterFormatTextOptions, // eslint-disable-line @typescript-eslint/no-unused-vars
         siteId?: string, // eslint-disable-line @typescript-eslint/no-unused-vars
     ): Promise<string> {
-        let language = await CoreLang.getCurrentLanguage();
+        // Get available languages.
+        const regex = /<(?:lang|span)[^>]+lang="([a-zA-Z0-9_-]+)"[^>]*>.*?<\/(?:lang|span)>/img;
+        const languages: Set<string> = new Set();
+        let match: RegExpExecArray | null;
 
-        // Match the current language.
+        while ((match = regex.exec(text))) {
-        const anyLangRegEx = /<(?:lang|span)[^>]+lang="[a-zA-Z0-9_-]+"[^>]*>(.*?)<\/(?:lang|span)>/g;
+            const language = match[1].toLowerCase().replace(/_/g, '-');
-        let currentLangRegEx = new RegExp('<(?:lang|span)[^>]+lang="' + language + '"[^>]*>(.*?)</(?:lang|span)>', 'g');
 
-        if (!text.match(currentLangRegEx)) {
+            languages.add(language);
-            // Current lang not found. Try to find the first language.
+        }
-            const matches = text.match(anyLangRegEx);
+
-            if (matches?.[0]) {
+        // Find language to use.
-                language = matches[0].match(/lang="([a-zA-Z0-9_-]+)"/)?.[1] || language;
+        let language: string | undefined = await CoreLang.getCurrentLanguage();
-                currentLangRegEx = new RegExp('<(?:lang|span)[^>]+lang="' + language + '"[^>]*>(.*?)</(?:lang|span)>', 'g');
+
-            } else {
+        if (!languages.has(language)) {
-                // No multi-lang tag found, stop.
+            language = CoreLang.getParentLanguage();
+        }
+
+        if (!language) {
             return text;
         }
-        }
 
-        // Extract contents of current language.
+        // Apply filter.
+        const anyLangRegEx = /<(lang|span)[^>]+lang="[a-zA-Z0-9_-]+"[^>]*>.*?<\/(lang|span)>/img;
+        const languageRegEx = language.replace(/-/g, '(?:-|_)');
+        const currentLangRegEx = new RegExp(`<(?:lang|span)[^>]+lang="${languageRegEx}"[^>]*>(.*?)</(?:lang|span)>`, 'img');
+
         text = text.replace(currentLangRegEx, '$1');
-        // Delete the rest of languages
         text = text.replace(anyLangRegEx, '');
 
         return text;

src/core/services/tests/lang.test.ts

@@ -0,0 +1,134 @@
+// (C) Copyright 2015 Moodle Pty Ltd.
+//
+// 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 { mockSingleton } from '@/testing/utils';
+import { CoreLang, CoreLangProvider, multilangString } from '@services/lang';
+
+describe('Lang', () => {
+
+    let lang: CoreLangProvider;
+    let currentLanguage: string;
+    let parentLanguage: string | undefined;
+
+    beforeEach(() => {
+        lang = new CoreLangProvider();
+        currentLanguage = 'en';
+
+        mockSingleton(CoreLang, {
+            getCurrentLanguage: () => Promise.resolve(currentLanguage),
+            getParentLanguage: () => parentLanguage,
+        });
+    });
+
+    it('filters multilang text', async () => {
+        await expectMultilangFilter('foo', 'foo');
+
+        await expectMultilangFilter(`
+            <span class="multilang" lang="es">Spanish</span>
+            <span class="multilang" lang="en">English</span>
+            <span class="multilang" lang="ja">Japanese</span>
+            <span class="multilang" lang="ES">(ES)</span>
+            <span class="multilang" lang="EN">(EN)</span>
+            <span class="multilang" lang="JA">(JA)</span>
+            <span lang="es" class="multilang">[Spain]</span>
+            <span lang="en" class="multilang">[United States]</span>
+            <span lang="ja" class="multilang">[Japan]</span>
+            text
+        `, 'English (EN) [United States] text');
+
+        await expectMultilangFilter(`
+            {mlang es}Spanish{mlang}
+            {mlang en}English{mlang}
+            {mlang ja}Japanese{mlang}
+            {mlang ES}(ES){mlang}
+            {mlang EN}(EN){mlang}
+            {mlang JA}(JA){mlang}
+            text
+        `, 'English (EN) text');
+    });
+
+    it('filters multilang text using regions', async () => {
+        currentLanguage = 'en-au';
+
+        await expectMultilangFilter(`
+            <span class="multilang" lang="en">English</span>
+            <span class="multilang" lang="en-US">English</span>
+            <span class="multilang" lang="en_US">(US)</span>
+            <span class="multilang" lang="en-AU">English</span>
+            <span class="multilang" lang="en_AU">(AU)</span>
+            text
+        `, 'English (AU) text');
+
+        await expectMultilangFilter(`
+            {mlang en}English{mlang}
+            {mlang en-US}English{mlang}
+            {mlang en_US}(US){mlang}
+            {mlang en-AU}English{mlang}
+            {mlang en_AU}(AU){mlang}
+            text
+        `, 'English (AU) text');
+    });
+
+    it('filters multilang text using the current language', async () => {
+        const multilangText = `
+            <span class="multilang" lang="es">Spanish</span>
+            <span class="multilang" lang="en">English</span>
+            <span class="multilang" lang="ja">Japanese</span>
+            text
+        `;
+        const multilang2Text = `
+            {mlang es}Spanish{mlang}
+            {mlang en}English{mlang}
+            {mlang ja}Japanese{mlang}
+            text
+        `;
+
+        currentLanguage = 'en';
+        await expectMultilangFilter(multilangText, 'English text');
+        await expectMultilangFilter(multilang2Text, 'English text');
+
+        currentLanguage = 'es';
+        await expectMultilangFilter(multilangText, 'Spanish text');
+        await expectMultilangFilter(multilang2Text, 'Spanish text');
+    });
+
+    it('filters multilang text using the parent language', async () => {
+        currentLanguage = 'ca';
+        parentLanguage = 'ja';
+
+        await expectMultilangFilter(`
+            <span class="multilang" lang="es">Spanish</span>
+            <span class="multilang" lang="en">English</span>
+            <span class="multilang" lang="ja">Japanese</span>
+            text
+        `, 'Japanese text');
+
+        await expectMultilangFilter(`
+            {mlang es}Spanish{mlang}
+            {mlang en}English{mlang}
+            {mlang ja}Japanese{mlang}
+            text
+        `, 'Japanese text');
+    });
+
+    /**
+     * Test multilang filter (normalizing whitespace).
+     */
+    async function expectMultilangFilter(text: string, expected: string): Promise<void> {
+        const actual = await lang.filterMultilang(multilangString(text));
+
+        expect(actual.replace(/\s+/g, ' ').trim()).toEqual(expected);
+    }
+
+});