--- /dev/null
+<?php
+
+namespace Drupal\Tests\Core\Cache\Context;
+
+use Drupal\Core\Cache\Context\SessionCacheContext;
+use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\HttpFoundation\RequestStack;
+
+/**
+ * @coversDefaultClass \Drupal\Core\Cache\Context\SessionCacheContext
+ * @group Cache
+ */
+class SessionCacheContextTest extends \PHPUnit_Framework_TestCase {
+
+ /**
+ * The request stack.
+ *
+ * @var \Symfony\Component\HttpFoundation\RequestStack
+ */
+ protected $requestStack;
+
+ /**
+ * The session object.
+ *
+ * @var \Symfony\Component\HttpFoundation\Session\SessionInterface|\PHPUnit_Framework_MockObject_MockObject
+ */
+ protected $session;
+
+ /**
+ * The session cache context.
+ *
+ * @var \Drupal\Core\Cache\Context\SessionCacheContext
+ */
+ protected $cacheContext;
+
+ public function setUp() {
+ $request = new Request();
+
+ $this->requestStack = new RequestStack();
+ $this->requestStack->push($request);
+
+ $this->session = $this->getMock('\Symfony\Component\HttpFoundation\Session\SessionInterface');
+ $request->setSession($this->session);
+
+ $this->cacheContext = new SessionCacheContext($this->requestStack);
+ }
+
+ /**
+ * @covers ::getContext
+ */
+ public function testSameContextForSameSession() {
+ $session_id = 'aSebeZ52bbM6SvADurQP89SFnEpxY6j8';
+ $this->session->expects($this->exactly(2))
+ ->method('getId')
+ ->will($this->returnValue($session_id));
+
+ $context1 = $this->cacheContext->getContext();
+ $context2 = $this->cacheContext->getContext();
+ $this->assertSame($context1, $context2);
+ $this->assertSame(FALSE, strpos($context1, $session_id), 'Session ID not contained in cache context');
+ }
+
+ /**
+ * @covers ::getContext
+ */
+ public function testDifferentContextForDifferentSession() {
+ $session1_id = 'pjH_8aSoofyCDQiuVYXJcbfyr-CPtkUY';
+ $this->session->expects($this->at(0))
+ ->method('getId')
+ ->will($this->returnValue($session1_id));
+
+ $session2_id = 'aSebeZ52bbM6SvADurQP89SFnEpxY6j8';
+ $this->session->expects($this->at(1))
+ ->method('getId')
+ ->will($this->returnValue($session2_id));
+
+ $context1 = $this->cacheContext->getContext();
+ $context2 = $this->cacheContext->getContext();
+ $this->assertNotEquals($context1, $context2);
+
+ $this->assertSame(FALSE, strpos($context1, $session1_id), 'Session ID not contained in cache context');
+ $this->assertSame(FALSE, strpos($context2, $session2_id), 'Session ID not contained in cache context');
+ }
+
+}