diff -u b/core/tests/Drupal/Tests/Core/Cache/Context/SessionCacheContextTest.php b/core/tests/Drupal/Tests/Core/Cache/Context/SessionCacheContextTest.php
--- b/core/tests/Drupal/Tests/Core/Cache/Context/SessionCacheContextTest.php
+++ b/core/tests/Drupal/Tests/Core/Cache/Context/SessionCacheContextTest.php
@@ -34,12 +34,6 @@
    */
   protected $session;
 
-  /**
-   * The session cache context.
-   *
-   * @var \Drupal\Core\Cache\Context\SessionCacheContext
-   */
-
   public function setUp() {
     $this->request = new Request();
 
@@ -100,8 +94,7 @@
   public function testContextWithoutSessionInRequest() {
     $cache_context = new SessionCacheContext($this->requestStack);
 
-    $context = $cache_context->getContext();
-    $this->assertSame('none', $context);
+    $this->assertSame('none', $cache_context->getContext());
   }
 
 }