MAGETWO-52143: Make Redis session adapter changes backwards compatible in 2.1

Author: dsikkema-magento

dev/tests/integration/testsuite/Magento/Framework/Session/SaveHandlerTest.php

@@ -12,6 +12,14 @@
 
 class SaveHandlerTest extends \PHPUnit_Framework_TestCase
 {
+    /** @var string Original session.save_handler ini config value */
+    private $originalSaveHandler;
+
+    public function setUp()
+    {
+        $this->originalSaveHandler = ini_get('session.save_handler');
+    }
+
     /**
      * Tests that the session handler is correctly set when object is created.
      *
@@ -36,7 +44,7 @@ public function testSetSaveHandler($deploymentConfigHandler, $iniHandler)
 
         // Set ini configuration
         if ($iniHandler) {
-            $oldIni = ini_set('session.save_handler', $iniHandler);
+            ini_set('session.save_handler', $iniHandler);
         }
 
         /** @var DeploymentConfig | \PHPUnit_Framework_MockObject_MockObject $deploymentConfigMock */
@@ -58,10 +66,12 @@ public function testSetSaveHandler($deploymentConfigHandler, $iniHandler)
             $expected,
             ObjectManager::getInstance()->get(ConfigInterface::class)->getOption('session.save_handler')
         );
+    }
 
-        // Reset ini configuration
-        if (isset($oldIni)) {
-            ini_set('session.save_handler', $oldIni);
+    public function tearDown()
+    {
+        if (isset($this->originalSaveHandler)) {
+            ini_set('session.save_handler', $this->originalSaveHandler);
         }
     }
 

lib/internal/Magento/Framework/Session/SaveHandler.php

@@ -6,6 +6,7 @@
 namespace Magento\Framework\Session;
 
 use Magento\Framework\App\DeploymentConfig;
+use Magento\Framework\App\ObjectManager;
 use Magento\Framework\Exception\SessionException;
 use Magento\Framework\Session\Config\ConfigInterface;
 
@@ -136,10 +137,8 @@ public function gc($maxLifetime)
      */
     private function getConfig()
     {
-        if (!($this->config instanceof ConfigInterface)) {
-            return \Magento\Framework\App\ObjectManager::getInstance()->get(
-                ConfigInterface::class
-            );
+        if ($this->config === null) {
+            $this->config = ObjectManager::getInstance()->get(ConfigInterface::class);
         }
         return $this->config;
     }