🌐(i18n) key crowdin frontend exports by locale

Crowdin exported the frontend translations to a folder named after
%two_letters_code%, so every regional variant of a language landed in the
same folder: zh-CN and zh-TW both gave "zh", and the last one downloaded
overwrote the other. Mapping the Chinese locales apart would have fixed
only that pair, and each new variant (pt-BR, es-MX, en-GB...) would have
needed its own entry.

Use %locale% instead, which is unique per locale, like the backend already
does with %locale_with_underscore%. format-deploy keeps the keys of
translations.json as they are today (fr, de...) and only keeps the region
(zh-cn, zh-tw) when several locales of the same language are translated.
The language detection and the language picker already match a locale
exactly before falling back to its language, so they need no change.

The export pattern is stored by Crowdin with the source file: the sources
must be uploaded again before the next download, and the zh-CN data that
was polluted with Traditional Chinese still needs to be re-uploaded.

Fixes #2749

CHANGELOG.md

@@ -100,6 +100,7 @@ and this project adheres to
 - 🐛(frontend) fix redirect after deleting a document #2706
 - 🐛(frontend) keep documents draggable with a mouse when zoomed #2727
 - 📝(docs) fix markdown typo in installation README #2766
+- 🐛(i18n) export locale correctly #2750
 
 ### Removed
 

crowdin/config.yml

@@ -23,7 +23,7 @@ files: [
   {
     source: "/frontend/packages/i18n/locales/impress/translations-crowdin.json",
     dest: "/frontend-impress.json",
-    translation: "/frontend/packages/i18n/locales/impress/%two_letters_code%/translations.json",
+    translation: "/frontend/packages/i18n/locales/impress/%locale%/translations.json",
     skip_untranslated_strings: true,
   },
 ]

src/frontend/packages/i18n/__tests__/i18n.test.ts

@@ -60,6 +60,36 @@ describe('integration testing on i18n package', () => {
     });
   });
 
+  test('cmd format-deploy keeps the region only when locales collide', () => {
+    // To be sure the tests folder is not here
+    fs.rmSync('./locales/tests', { recursive: true, force: true });
+
+    const locales = {
+      en: 'My test',
+      'fr-FR': 'Mon test',
+      'zh-CN': '简',
+      'zh-TW': '繁',
+    };
+    Object.entries(locales).forEach(([locale, message]) => {
+      fs.mkdirSync(`./locales/tests/${locale}/`, { recursive: true });
+      fs.writeFileSync(
+        `./locales/tests/${locale}/translations.json`,
+        JSON.stringify({ test: { message } }),
+        'utf8',
+      );
+    });
+
+    const output = './locales/tests/translations.json';
+    execSync(`node ./format-deploy.mjs --app=tests --output=${output}`);
+    const json = JSON.parse(fs.readFileSync(output, 'utf8'));
+    expect(json).toEqual({
+      en: { translation: { test: 'My test' } },
+      fr: { translation: { test: 'Mon test' } },
+      'zh-cn': { translation: { test: '简' } },
+      'zh-tw': { translation: { test: '繁' } },
+    });
+  });
+
   test('cmd format-deploy throws an error when translation file is not found', () => {
     // To be sure the tests folder is not here
     fs.rmSync('./locales/tests', { recursive: true, force: true });

src/frontend/packages/i18n/format-deploy.mjs

@@ -11,13 +11,31 @@ const folderPath = './locales/' + app;
 const namefile = 'translations.json';
 const jsonI18n = {};
 
-// Fetch the files in the locales folder
-fs.readdirSync(folderPath).map((language) => {
-  const languagePath = path.join(folderPath, path.sep, language);
+// Crowdin outputs one folder per locale (fr-FR, zh-CN, zh-TW, en...)
+const locales = fs.readdirSync(folderPath).filter((entry) => {
   // Crowdin output file in folder, we want to treat only these ones
-  if (!fs.lstatSync(languagePath).isDirectory()) {
-    return;
-  }
+  return fs.lstatSync(path.join(folderPath, entry)).isDirectory();
+});
+
+const getLanguage = (locale) => locale.split(/[-_]/)[0].toLowerCase();
+
+const localesPerLanguage = {};
+locales.forEach((locale) => {
+  const language = getLanguage(locale);
+  localesPerLanguage[language] = (localesPerLanguage[language] ?? 0) + 1;
+});
+
+// The language alone (fr) is enough when only one locale of it is translated,
+// the region is kept (zh-cn, zh-tw) when the locales would otherwise collide.
+const getKey = (locale) =>
+  localesPerLanguage[getLanguage(locale)] > 1
+    ? locale.replace('_', '-').toLowerCase()
+    : getLanguage(locale);
+
+// Fetch the files in the locales folder
+locales.forEach((locale) => {
+  const language = getKey(locale);
+  const languagePath = path.join(folderPath, path.sep, locale);
 
   jsonI18n[language] = {
     translation: {},