Added error in res.render() callback test

test/res.render.js

@@ -262,6 +262,31 @@ describe('res', function(){
           done();
         });
       })
+      
+      describe('in the callback', function(){
+        it('should next(err)', function(done){
+          var app = express();
+
+          app.set('views', __dirname + '/fixtures');
+
+          app.use(function(req, res){
+            res.render('user.jade', function(err){
+              req.foo();
+            });
+          });
+
+          app.use(function(err, req, res, next){
+            res.end(err.message);
+          });
+
+          request(app)
+          .get('/')
+          .end(function(res){
+            res.body.should.match(/has no method 'foo'/);
+            done();
+          });
+        })
+      })
     })
   })