fix(service): fix infinite loop when fallback language async loading …

…fails

src/service/translate.js

@@ -1910,7 +1910,7 @@ function $translate($STORAGE_KEY, $windowProvider, $translateSanitizationProvide
             return translation;
           }, function (key) {
             // find first available fallback language if that request has failed
-            if (!$uses && $fallbackLanguage && $fallbackLanguage.length > 0) {
+            if (!$uses && $fallbackLanguage && $fallbackLanguage.length > 0 && $fallbackLanguage[0] !== key) {
               return $translate.use($fallbackLanguage[0]).then(deferred.resolve, deferred.reject);
             } else {
               return deferred.reject(key);

test/unit/service/translate.spec.js

@@ -2877,4 +2877,45 @@ describe('pascalprecht.translate', function () {
       expect(secondLanguageResponded).toEqual(true);
     }));
   });
+
+  // Spec for edge case: preferred and fallback language are not found
+  describe('$translate with async loading having an invalid preferredLang and one fallbackLang existing', function () {
+
+    var theFallbackLangKey = 'ef_GH',
+      thePreferredLangKey = 'ab_CD';
+
+    beforeEach(module('pascalprecht.translate', function ($translateProvider, $provide) {
+
+      $translateProvider.useLoader('customLoader');
+
+      $translateProvider.preferredLanguage(thePreferredLangKey);
+      $translateProvider.fallbackLanguage(theFallbackLangKey);
+
+      $provide.service('customLoader', function ($q) {
+        return function (options) {
+          var locale = options.key;
+          return $q.reject(locale);
+        };
+      });
+    }));
+
+    var $translate;
+
+    beforeEach(inject(function ($timeout, _$translate_, $rootScope) {
+      $translate = _$translate_;
+      $rootScope.$digest();
+    }));
+
+    it('should fail without going into infinite loop', inject(function ($rootScope) {
+
+      var failed = false;
+
+      $translate('greeting').catch(function () {
+        failed = true;
+      });
+
+      $rootScope.$digest();
+      expect(failed).toEqual(true);
+    }));
+  });
 });