diff -u b/core/modules/field/tests/src/Kernel/FieldDefinitionAvailabilityTest.php b/core/modules/field/tests/src/Kernel/FieldDefinitionAvailabilityTest.php
--- b/core/modules/field/tests/src/Kernel/FieldDefinitionAvailabilityTest.php
+++ b/core/modules/field/tests/src/Kernel/FieldDefinitionAvailabilityTest.php
@@ -16,7 +16,16 @@
 class FieldDefinitionAvailabilityTest extends KernelTestBase {
 
   /**
+   * Modules to enable.
+   *
+   * The test runner will merge the $modules lists from this class, the class
+   * it extends, and so on up the class hierarchy. It is not necessary to
+   * include modules in your list that a parent class has already declared.
+   *
    * @var array
+   *
+   * @see \Drupal\Tests\KernelTestBase::enableModules()
+   * @see \Drupal\Tests\KernelTestBase::bootKernel()
    */
   public static $modules = ['system'];
 
@@ -33,25 +42,15 @@
       if ($module->origin === 'core'
         && empty($module->info['hidden'])
         && $module->status == FALSE
-        && $module->info['package'] !== 'Testing'
-        && (
-          is_readable($module->getPath() . '/src/Entity')
-          || is_readable($module->getPath() . '/src/Plugin/Field')
-        )) {
+        && $module->info['package'] !== 'Testing') {
         return TRUE;
       }
       return FALSE;
     });
 
-    if (!empty($modules['rest'])) {
-      unset($modules['rest']);
-    }
     $this->enableModules(array_keys($modules));
 
     /** @var \Drupal\Component\Plugin\Discovery\DiscoveryInterface $field_type_manager */
-    /*$field_type_manager = \Drupal::service('plugin.manager.field.field_type');*/
-
-    /** @var \Drupal\Component\Plugin\Discovery\DiscoveryInterface $field_type_manager */
     $field_formatter_manager = \Drupal::service('plugin.manager.field.formatter');
 
     /** @var \Drupal\Component\Plugin\Discovery\DiscoveryInterface $field_type_manager */
@@ -63,7 +62,6 @@
     /** @var \Drupal\Core\Entity\EntityTypeManagerInterface $entity_type_manager */
     $entity_type_manager = \Drupal::service('entity_type.manager');
 
-
     /** @var \Drupal\Core\Field\BaseFieldDefinition[][] $field_definitions */
     $field_definitions = [];
     /** @var \Drupal\Core\Entity\EntityTypeInterface[] $content_entity_types */
@@ -84,7 +82,7 @@
             $field_formatter_manager->getDefinition($view_display_options['type']);
           }
           catch (PluginNotFoundException $e) {
-            $plugin_not_found[] = "PluginNotFoundException here for '{$entity_type_id}' entity type in '{$field_id}' field view display options. Original message: {$e->getMessage()}";
+            $plugin_not_found[] = "PluginNotFoundException here for \"{$entity_type_id}\" entity type in \"{$field_id}\" field view display options. Original message: {$e->getMessage()}";
           }
         }
         $form_display_options = $field_definition->getDisplayOptions('form');
@@ -93,7 +91,7 @@
             $field_widget_manager->getDefinition($form_display_options['type']);
           }
           catch (PluginNotFoundException $e) {
-            $plugin_not_found[] = "PluginNotFoundException here for '{$entity_type_id}' entity type in '{$field_id}' field form display options. Original message: {$e->getMessage()}";
+            $plugin_not_found[] = "PluginNotFoundException here for \"{$entity_type_id}\" entity type in \"{$field_id}\" field form display options. Original message: {$e->getMessage()}";
           }
         }
       }