Fix double base directory in unauthorized redirects.

Turn off base path inclusion when the referrer is generated. In the case
where there is no referrer header, we need to omit the base path as
redirect() will add one in.

Including a base path causes apps in sub-directories to behave
incorrectly.

Refs #7205

src/Controller/Component/AuthComponent.php

@@ -405,6 +405,7 @@ class AuthComponent extends Component
             if (!empty($this->_config['loginRedirect'])) {
                 $default = $this->_config['loginRedirect'];
             }
+            $default['_base'] = false;
             $url = $controller->referer($default, true);
         } else {
             $url = $this->_config['unauthorizedRedirect'];

tests/TestCase/Controller/Component/AuthComponentTest.php

@@ -734,24 +734,32 @@ class AuthComponentTest extends TestCase
     public function testDefaultToLoginRedirect()
     {
         $url = '/party/on';
-        $this->Auth->request = $Request = new Request($url);
-        $Request->env('HTTP_REFERER', false);
-        $this->Auth->request->addParams(Router::parse($url));
+        $this->Auth->request = $request = new Request($url);
+        $request->env('HTTP_REFERER', false);
+        $request->addParams(Router::parse($url));
+        $request->addPaths([
+            'base' => 'dirname',
+            'webroot' => '/dirname/',
+        ]);
+        Router::pushRequest($request);
+
         $this->Auth->config('authorize', ['Controller']);
         $this->Auth->setUser(['username' => 'mariano', 'password' => 'cake']);
         $this->Auth->config('loginRedirect', [
-            'controller' => 'something', 'action' => 'else'
+            'controller' => 'something',
+            'action' => 'else'
         ]);
 
         $response = new Response();
         $Controller = $this->getMock(
             'Cake\Controller\Controller',
             ['on', 'redirect'],
-            [$Request, $response]
+            [$request, $response]
         );
         $event = new Event('Controller.startup', $Controller);
 
-        $expected = Router::url($this->Auth->config('loginRedirect'));
+        // Should not contain basedir when redirect is called.
+        $expected = '/something/else';
         $Controller->expects($this->once())
             ->method('redirect')
             ->with($this->equalTo($expected));