[TwigBridge] fixed AppVariable compat with older Symfony versions

src/Symfony/Bridge/Twig/AppVariable.php

@@ -74,7 +74,7 @@ class AppVariable
             throw new \RuntimeException('The "app.security" variable is not available.');
         }
 
-        return $this->container->get('security');
+        return $this->container->get('security.context');
     }
 
     /**
@@ -87,9 +87,13 @@ class AppVariable
     public function getUser()
     {
         if (null === $this->tokenStorage) {
+            if (null === $this->container) {
                 throw new \RuntimeException('The "app.user" variable is not available.');
             }
 
+            $this->tokenStorage = $this->container->get('security.context');
+        }
+
         if (!$token = $this->tokenStorage->getToken()) {
             return;
         }
@@ -108,9 +112,13 @@ class AppVariable
     public function getRequest()
     {
         if (null === $this->requestStack) {
+            if (null === $this->container) {
                 throw new \RuntimeException('The "app.request" variable is not available.');
             }
 
+            $this->requestStack = $this->container->get('request_stack');
+        }
+
         return $this->requestStack->getCurrentRequest();
     }
 
@@ -121,10 +129,6 @@ class AppVariable
      */
     public function getSession()
     {
-        if (null === $this->requestStack) {
-            throw new \RuntimeException('The "app.session" variable is not available.');
-        }
-
         if ($request = $this->getRequest()) {
             return $request->getSession();
         }
@@ -138,9 +142,13 @@ class AppVariable
     public function getEnvironment()
     {
         if (null === $this->environment) {
+            if (null === $this->container) {
                 throw new \RuntimeException('The "app.environment" variable is not available.');
             }
 
+            $this->environment = $this->container->getParameter('kernel.environment');
+        }
+
         return $this->environment;
     }
 
@@ -152,9 +160,13 @@ class AppVariable
     public function getDebug()
     {
         if (null === $this->debug) {
+            if (null === $this->container) {
                 throw new \RuntimeException('The "app.debug" variable is not available.');
             }
 
+            $this->debug = $this->container->getParameter('kernel.debug');
+        }
+
         return $this->debug;
     }
 }