From 71fb19861dda2fce3dcef1b8a45ab9f3d35269b0 Mon Sep 17 00:00:00 2001
From: slowbackspace <slowbackspace@gmail.com>
Date: Fri, 12 Apr 2019 17:24:11 +0200
Subject: [PATCH 1/2] getInitialLocale now accepts navigatorLanguage as param

---
 src/actions/LocalStorageActions.js | 2 +-
 src/utils/l10n.js                  | 6 ++++--
 2 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/src/actions/LocalStorageActions.js b/src/actions/LocalStorageActions.js
index 2a2a2736..09f31b12 100644
--- a/src/actions/LocalStorageActions.js
+++ b/src/actions/LocalStorageActions.js
@@ -277,7 +277,7 @@ const loadStorageData = (): ThunkAction => (dispatch: Dispatch): void => {
     if (language) {
         dispatch(WalletActions.fetchLocale(JSON.parse(language)));
     } else {
-        dispatch(WalletActions.fetchLocale(l10nUtils.getInitialLocale()));
+        dispatch(WalletActions.fetchLocale(l10nUtils.getInitialLocale(navigator.language)));
     }
 
     const localCurrency: ?string = storageUtils.get(TYPE, KEY_LOCAL_CURRENCY);
diff --git a/src/utils/l10n.js b/src/utils/l10n.js
index 11170d0f..8288accb 100644
--- a/src/utils/l10n.js
+++ b/src/utils/l10n.js
@@ -1,7 +1,9 @@
 import { LANGUAGE } from 'config/app';
 
-export const getInitialLocale = (defaultLocale = 'en') => {
-    const browserLocale = navigator.language.split('-')[0];
+export const getInitialLocale = (navigatorLanguage, defaultLocale = 'en') => {
+    if (!navigatorLanguage) return defaultLocale;
+
+    const browserLocale = navigatorLanguage.split('-')[0];
     if (LANGUAGE.some(e => e.code === browserLocale)) {
         // Array of supported languages contains the locale we're looking for
         return browserLocale;

From 9ea0a3fe6631f3632152cc9918567d0aeca99efb Mon Sep 17 00:00:00 2001
From: slowbackspace <slowbackspace@gmail.com>
Date: Fri, 12 Apr 2019 17:24:15 +0200
Subject: [PATCH 2/2] add tests

---
 src/utils/__tests__/l10n.js | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)
 create mode 100644 src/utils/__tests__/l10n.js

diff --git a/src/utils/__tests__/l10n.js b/src/utils/__tests__/l10n.js
new file mode 100644
index 00000000..e2e5a557
--- /dev/null
+++ b/src/utils/__tests__/l10n.js
@@ -0,0 +1,17 @@
+import * as utils from '../l10n';
+
+describe('l10n utils: getInitialLocale', () => {
+    it('default lang', () => {
+        expect(utils.getInitialLocale(0)).toBe('en');
+        expect(utils.getInitialLocale(null)).toBe('en');
+        expect(utils.getInitialLocale(undefined)).toBe('en');
+        expect(utils.getInitialLocale('dadada')).toBe('en');
+        expect(utils.getInitialLocale('')).toBe('en');
+    });
+
+    it('browser locales', () => {
+        expect(utils.getInitialLocale('zh')).toBe('zh');
+        expect(utils.getInitialLocale('cs-CZ')).toBe('cs');
+        expect(utils.getInitialLocale('en_GB')).toBe('en');
+    });
+});