From c4a5b67a5af04bfd57b9b203ee2685cf33b42d90 Mon Sep 17 00:00:00 2001
From: Christian Flothmann <christian.flothmann@xabbuh.de>
Date: Sat, 5 Mar 2016 08:50:24 +0100
Subject: [PATCH] exception when registering bags for started sessions

---
 .../Session/Storage/NativeSessionStorage.php           |  4 ++++
 .../Tests/Session/Storage/NativeSessionStorageTest.php | 10 ++++++++++
 2 files changed, 14 insertions(+)

diff --git a/src/Symfony/Component/HttpFoundation/Session/Storage/NativeSessionStorage.php b/src/Symfony/Component/HttpFoundation/Session/Storage/NativeSessionStorage.php
index 137f0e8e1c..aa4a237cdd 100644
--- a/src/Symfony/Component/HttpFoundation/Session/Storage/NativeSessionStorage.php
+++ b/src/Symfony/Component/HttpFoundation/Session/Storage/NativeSessionStorage.php
@@ -260,6 +260,10 @@ class NativeSessionStorage implements SessionStorageInterface
      */
     public function registerBag(SessionBagInterface $bag)
     {
+        if ($this->started) {
+            throw new \LogicException('Cannot register a bag when the session is already started.');
+        }
+
         $this->bags[$bag->getName()] = $bag;
     }
 
diff --git a/src/Symfony/Component/HttpFoundation/Tests/Session/Storage/NativeSessionStorageTest.php b/src/Symfony/Component/HttpFoundation/Tests/Session/Storage/NativeSessionStorageTest.php
index 121cff37a1..160b575862 100644
--- a/src/Symfony/Component/HttpFoundation/Tests/Session/Storage/NativeSessionStorageTest.php
+++ b/src/Symfony/Component/HttpFoundation/Tests/Session/Storage/NativeSessionStorageTest.php
@@ -83,6 +83,16 @@ class NativeSessionStorageTest extends \PHPUnit_Framework_TestCase
         $storage->getBag('non_existing');
     }
 
+    /**
+     * @expectedException \LogicException
+     */
+    public function testRegisterBagForAStartedSessionThrowsException()
+    {
+        $storage = $this->getStorage();
+        $storage->start();
+        $storage->registerBag(new AttributeBag());
+    }
+
     public function testGetId()
     {
         $storage = $this->getStorage();