res -> locals -> res recursion escaping

i18n.js

@@ -436,12 +436,26 @@ module.exports = (function() {
 
     // consider res
     if (targetObject.res && !skipImplicitObjects) {
-      i18n.setLocale(targetObject.res, targetObject.locale);
+
+      // escape recursion
+      if (targetObject.res.locals) {
+        i18n.setLocale(targetObject.res, targetObject.locale, true);
+        i18n.setLocale(targetObject.res.locals, targetObject.locale, true);
+      } else {
+        i18n.setLocale(targetObject.res, targetObject.locale);
+      }
     }
 
     // consider locals
     if (targetObject.locals && !skipImplicitObjects) {
-      i18n.setLocale(targetObject.locals, targetObject.locale);
+
+      // escape recursion
+      if (targetObject.locals.res) {
+        i18n.setLocale(targetObject.locals, targetObject.locale, true);
+        i18n.setLocale(targetObject.locals.res, targetObject.locale, true);
+      } else {
+        i18n.setLocale(targetObject.locals, targetObject.locale);
+      }
     }
 
     return i18n.getLocale(targetObject);
@@ -574,13 +588,16 @@ module.exports = (function() {
    */
   var applyAPItoObject = function(object) {
 
+    var alreadySetted = true;
+
     // attach to itself if not provided
     for (var method in api) {
       if (api.hasOwnProperty(method)) {
         var alias = api[method];
 
         // be kind rewind, or better not touch anything already existing
         if (!object[alias]) {
+          alreadySetted = false;
           object[alias] = i18n[method].bind(object);
         }
       }
@@ -591,6 +608,11 @@ module.exports = (function() {
       object.locale = defaultLocale;
     }
 
+    // escape recursion
+    if (alreadySetted) {
+      return;
+    }
+
     // attach to response if present (ie. in express)
     if (object.res) {
       applyAPItoObject(object.res);

test/i18n.configureApi.js

@@ -68,4 +68,18 @@ describe('configure api', function() {
         });
         should.equal(typeof customObject.__, 'undefined');
     });
+
+    it('should escape res -> locals -> res recursion', function() {
+        var customObject = {};
+        customObject.locals = { res: customObject };
+        reconfigure({
+            locales: ['en', 'de'],
+            register: customObject,
+            api: {
+              '__': 't'
+            }
+        });
+        should.equal(typeof customObject.t, 'function');
+        should.equal(typeof customObject.locals.t, 'function');
+    });
 });

test/i18n.setLocale.js

@@ -239,4 +239,18 @@ describe('Locale switching should work on req and res', function() {
     res.locals.__('Hello').should.equal('Bonjour');
   });
 
+
+  it('setLocale(object) should escape res -> locals -> res recursion', function() {
+    // add locals to res
+    res.locals = { res: res };
+
+    // add res to req to simulate express 4.x schema
+    req.res = res;
+    i18n.init(req, res);
+    i18n.setLocale(req, 'fr');
+
+    res.locale.should.equal('fr');
+    res.locals.locale.should.equal('fr');
+  });
+
 });