Set-Cookie Header getting corrupted because we end up with array inside array

lib/patch.js

@@ -47,9 +47,13 @@ if (!res._hasConnectPatch) {
     // special-case Set-Cookie
     if (this._headers && 'set-cookie' == key) {
       if (prev = this.getHeader(field)) {
-        val = Array.isArray(prev)
-          ? prev.concat(val)
-          : [prev, val];
+          if (Array.isArray(prev)) {
+              val = prev.concat(val);
+          } else if (Array.isArray(val)) {
+              val = val.concat(prev);
+          } else {
+              val = [prev, val];
+          }
       }
     // charset
     } else if ('content-type' == key && this.charset) {

test/patch.js

@@ -82,5 +82,64 @@ describe('patch', function(){
       })
     })
 
+    describe('should handle set-cookie setting multiple cookies as array', function(){
+        it('should be emitted', function(done){
+            var app = connect();
+
+            app.use(function(req, res, next){
+                res.on('header', function(){
+                    res.setHeader('Set-Cookie', ['foo1', 'bar1']);
+                    res.setHeader('Set-Cookie', ['foo2', 'bar2']);
+                });
+
+                next();
+            });
+
+            app.use(function(req, res){
+                res.end();
+            })
+
+            app.request()
+            .get('/')
+            .end(function(res){
+                res.headers['set-cookie'].should.include('foo1');
+                res.headers['set-cookie'].should.include('bar1');
+                res.headers['set-cookie'].should.include('foo2');
+                res.headers['set-cookie'].should.include('bar2');
+                done();
+            });
+        })
+    })
+
+    describe('should handle set-cookie setting multiple cookies as array and string', function(){
+        it('should be emitted', function(done){
+            var app = connect();
+
+            app.use(function(req, res, next){
+                res.on('header', function(){
+                    res.setHeader('Set-Cookie', ['foo1', 'bar1']);
+                    res.setHeader('Set-Cookie', 'foo2');
+                });
+
+                next();
+            });
+
+            app.use(function(req, res){
+                res.end();
+            })
+
+            app.request()
+            .get('/')
+            .end(function(res){
+                res.headers['set-cookie'].should.include('foo1');
+                res.headers['set-cookie'].should.include('bar1');
+                res.headers['set-cookie'].should.include('foo2');
+                done();
+            });
+        })
+    })
+
+
+
   })
-})
+})