if defaultValue is passed in not ready t functio (via useTranslation)…

… return that instead of the key, even though the user-land could should be fixed #1618

CHANGELOG.md

@@ -1,3 +1,7 @@
+### 12.2.0
+
+- if defaultValue is passed in not ready t functio (via useTranslation) return that instead of the key, even though the user-land could should be fixed [1618](https://github.com/i18next/react-i18next/issues/1618)
+
 ### 12.1.5
 
 - fix react merged types [1606](https://github.com/i18next/react-i18next/pull/1606) originally introduced with #1531 to address #1506

src/useTranslation.js

@@ -18,7 +18,16 @@ export function useTranslation(ns, props = {}) {
   if (i18n && !i18n.reportNamespaces) i18n.reportNamespaces = new ReportNamespaces();
   if (!i18n) {
     warnOnce('You will need to pass in an i18next instance by using initReactI18next');
-    const notReadyT = (k) => (Array.isArray(k) ? k[k.length - 1] : k);
+    const notReadyT = (k, optsOrDefaultValue) => {
+      if (typeof optsOrDefaultValue === 'string') return optsOrDefaultValue;
+      if (
+        optsOrDefaultValue &&
+        typeof optsOrDefaultValue === 'object' &&
+        typeof optsOrDefaultValue.defaultValue === 'string'
+      )
+        return optsOrDefaultValue.defaultValue;
+      return Array.isArray(k) ? k[k.length - 1] : k;
+    };
     const retNotReady = [notReadyT, {}, false];
     retNotReady.t = notReadyT;
     retNotReady.i18n = {};

test/useTranslation.loading.spec.js

@@ -43,4 +43,13 @@ describe('useTranslation loading ns', () => {
     await waitForNextUpdate();
     expect(t('key1')).toBe('test');
   });
+
+  it('should return defaultValue if i18n instance not found', async () => {
+    const { result } = renderHook(() =>
+      useTranslation('common', { i18n: newI18n, useSuspense: false }),
+    );
+    const { t } = result.current;
+    expect(t('key1', 'my default value')).toBe('my default value');
+    expect(t('key1', { defaultValue: 'my default value' })).toBe('my default value');
+  });
 });