From fd30f4a21d6f44dda89a13f01f222d29aa270aed Mon Sep 17 00:00:00 2001
From: Titouan Galopin <galopintitouan@gmail.com>
Date: Mon, 10 Sep 2018 21:53:03 +0200
Subject: [PATCH] Allow reuse of Session between requests

---
 .../HttpFoundation/Session/Session.php        |  4 +++-
 .../Tests/Session/SessionTest.php             | 21 +++++++++++++++++++
 .../Storage/MockArraySessionStorageTest.php   |  2 +-
 3 files changed, 25 insertions(+), 2 deletions(-)

diff --git a/src/Symfony/Component/HttpFoundation/Session/Session.php b/src/Symfony/Component/HttpFoundation/Session/Session.php
index 725b97ea4e..8293cf2871 100644
--- a/src/Symfony/Component/HttpFoundation/Session/Session.php
+++ b/src/Symfony/Component/HttpFoundation/Session/Session.php
@@ -178,7 +178,9 @@ class Session implements SessionInterface, \IteratorAggregate, \Countable
      */
     public function setId($id)
     {
-        $this->storage->setId($id);
+        if ($this->storage->getId() !== $id) {
+            $this->storage->setId($id);
+        }
     }
 
     /**
diff --git a/src/Symfony/Component/HttpFoundation/Tests/Session/SessionTest.php b/src/Symfony/Component/HttpFoundation/Tests/Session/SessionTest.php
index 8e3d55ecbd..acd5513896 100644
--- a/src/Symfony/Component/HttpFoundation/Tests/Session/SessionTest.php
+++ b/src/Symfony/Component/HttpFoundation/Tests/Session/SessionTest.php
@@ -70,6 +70,27 @@ class SessionTest extends TestCase
         $this->assertEquals('0123456789abcdef', $this->session->getId());
     }
 
+    public function testSetIdAfterStart()
+    {
+        $this->session->start();
+        $id = $this->session->getId();
+
+        $e = null;
+        try {
+            $this->session->setId($id);
+        } catch (\Exception $e) {
+        }
+
+        $this->assertNull($e);
+
+        try {
+            $this->session->setId('different');
+        } catch (\Exception $e) {
+        }
+
+        $this->assertInstanceOf('\LogicException', $e);
+    }
+
     public function testSetName()
     {
         $this->assertEquals('MOCKSESSID', $this->session->getName());
diff --git a/src/Symfony/Component/HttpFoundation/Tests/Session/Storage/MockArraySessionStorageTest.php b/src/Symfony/Component/HttpFoundation/Tests/Session/Storage/MockArraySessionStorageTest.php
index 0c182e0b0b..893e120ce1 100644
--- a/src/Symfony/Component/HttpFoundation/Tests/Session/Storage/MockArraySessionStorageTest.php
+++ b/src/Symfony/Component/HttpFoundation/Tests/Session/Storage/MockArraySessionStorageTest.php
@@ -48,7 +48,7 @@ class MockArraySessionStorageTest extends TestCase
         $this->data = array(
             $this->attributes->getStorageKey() => array('foo' => 'bar'),
             $this->flashes->getStorageKey() => array('notice' => 'hello'),
-            );
+        );
 
         $this->storage = new MockArraySessionStorage();
         $this->storage->registerBag($this->flashes);