added a new behaviour for responses that enable the tuple to be in the form of (response, headers) and continiue to support the (response, status, headers) format.

flask/testsuite/basic.py

@@ -735,7 +735,17 @@ class BasicFunctionalityTestCase(FlaskTestCase):
             return 'Meh', 400, {
                 'X-Foo': 'Testing',
                 'Content-Type': 'text/plain; charset=utf-8'
+            } 
+        @app.route("/two_args")
+        def from_two_args_tuple():
+            return "Hello", {
+                'X-Foo': 'Test',
+                'Content-Type': 'text/plain; charset=utf-8'
             }
+        @app.route("/args_status")
+        def from_status_tuple():
+            return "Hi, status!", 400
+
         c = app.test_client()
         self.assert_equal(c.get('/unicode').data, u'Hällo Wörld'.encode('utf-8'))
         self.assert_equal(c.get('/string').data, u'Hällo Wörld'.encode('utf-8'))
@@ -745,6 +755,18 @@ class BasicFunctionalityTestCase(FlaskTestCase):
         self.assert_equal(rv.status_code, 400)
         self.assert_equal(rv.mimetype, 'text/plain')
 
+        rv2 = c.get("/two_args")
+        self.assert_equal(rv2.data, b'Hello')
+        self.assert_equal(rv2.headers['X-Foo'], 'Test')
+        self.assert_equal(rv2.status_code, 200)
+        self.assert_equal(rv2.mimetype, 'text/plain')
+
+        rv3 = c.get("/args_status")
+        self.assert_equal(rv3.data, b'Hi, status!')
+        self.assert_equal(rv3.status_code, 400)
+        self.assert_equal(rv3.mimetype, 'text/html')
+
+
     def test_make_response(self):
         app = flask.Flask(__name__)
         with app.test_request_context():