diff --git a/core/modules/system/src/Tests/Common/SystemListingTest.php b/core/modules/system/src/Tests/Common/SystemListingTest.php
index f2bd4bf..9d4e2fc 100644
--- a/core/modules/system/src/Tests/Common/SystemListingTest.php
+++ b/core/modules/system/src/Tests/Common/SystemListingTest.php
@@ -54,23 +54,23 @@ function testDirectoryPrecedence() {
   /**
    * Tests that directories matching file_scan_ignore_directories are ignored
    */
-  function testFileScanIgnoreDirectory() {
+  public function testFileScanIgnoreDirectory() {
     $listing = new ExtensionDiscovery(\Drupal::root(), FALSE);
     $listing->setProfileDirectories(array('core/profiles/testing'));
     $files = $listing->scan('module');
-    $this->assertTrue(isset($files['drupal_system_listing_compatible_test']));
+    $this->assertArrayHasKey('drupal_system_listing_compatible_test', $files);
 
     // Reset the static to force a rescan of the directories.
     $reflected_class = new \ReflectionClass(ExtensionDiscovery::class);
     $reflected_property = $reflected_class->getProperty('files');
-    $reflected_property->setAccessible(true);
+    $reflected_property->setAccessible(TRUE);
     $reflected_property->setValue($reflected_class, []);
 
-    $this->settingsSet('file_scan_ignore_directories', ['drupal_system_listing_compatible_test']);
+    $this->setSetting('file_scan_ignore_directories', ['drupal_system_listing_compatible_test']);
     $listing = new ExtensionDiscovery(\Drupal::root(), FALSE);
     $listing->setProfileDirectories(array('core/profiles/testing'));
     $files = $listing->scan('module');
-    $this->assertFalse(isset($files['drupal_system_listing_compatible_test']));
+    $this->assertArrayNotHasKey('drupal_system_listing_compatible_test', $files);
   }
 
 }