diff --git a/core/phpunit.xml.dist b/core/phpunit.xml.dist
index aa4acfd..bf175e2 100644
--- a/core/phpunit.xml.dist
+++ b/core/phpunit.xml.dist
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 
-<phpunit bootstrap="tests/bootstrap.php" colors="true">
+<phpunit bootstrap="tests/bootstrap.php" colors="true" strict="true">
   <php>
     <!-- Set error reporting to E_ALL. -->
     <ini name="error_reporting" value="32767"/>
diff --git a/core/tests/Drupal/Tests/Core/EventSubscriber/AccessSubscriberTest.php b/core/tests/Drupal/Tests/Core/EventSubscriber/AccessSubscriberTest.php
index 746b5c8..45b86f8 100644
--- a/core/tests/Drupal/Tests/Core/EventSubscriber/AccessSubscriberTest.php
+++ b/core/tests/Drupal/Tests/Core/EventSubscriber/AccessSubscriberTest.php
@@ -151,23 +151,23 @@ public function testAccessSubscriberOnlyChecksForRequestsWithRouteObject() {
    * Tests that if access is granted, AccessSubscriber will not throw a Symfony\Component\HttpKernel\Exception\AccessDeniedHttpException exception.
    */
   public function testAccessSubscriberDoesNotAlterRequestIfAccessManagerGrantsAccess() {
-    $this->parameterBag->expects($this->any())
+    $this->parameterBag->expects($this->once())
       ->method('has')
       ->with(RouteObjectInterface::ROUTE_OBJECT)
       ->will($this->returnValue(TRUE));
 
-    $this->parameterBag->expects($this->any())
+    $this->parameterBag->expects($this->once())
       ->method('get')
       ->with(RouteObjectInterface::ROUTE_OBJECT)
       ->will($this->returnValue($this->route));
 
-    $this->accessManager->expects($this->any())
+    $this->accessManager->expects($this->once())
       ->method('check')
-      ->with($this->anything())
+      ->with($this->equalTo($this->route))
       ->will($this->returnValue(TRUE));
 
     $subscriber = new AccessSubscriber($this->accessManager, $this->currentUser);
-    // The onKernelRequestAccessCheck() method has no return value.
+    // We're testing that no exception is thrown in this case. There is no return.
     $subscriber->onKernelRequestAccessCheck($this->event);
   }