.../link/tests/src/Kernel/LinkItemSerializationTest.php       | 11 +++++++----
 .../serialization/tests/src/Kernel/MapDataNormalizerTest.php  |  1 -
 .../Functional/Rest/EntityTestMapFieldResourceTestBase.php    |  7 +++++--
 3 files changed, 12 insertions(+), 7 deletions(-)

diff --git a/core/modules/link/tests/src/Kernel/LinkItemSerializationTest.php b/core/modules/link/tests/src/Kernel/LinkItemSerializationTest.php
index 0804607..dde7dc1 100644
--- a/core/modules/link/tests/src/Kernel/LinkItemSerializationTest.php
+++ b/core/modules/link/tests/src/Kernel/LinkItemSerializationTest.php
@@ -17,17 +17,20 @@
 class LinkItemSerializationTest extends FieldKernelTestBase {
 
   /**
-   * Modules to enable.
-   *
-   * @var array
+   * {@inheritdoc}
    */
   public static $modules = ['link', 'serialization'];
 
   /**
-   * The serializer type.
+   * The serializer service.
+   *
+   * @var \Symfony\Component\Serializer\SerializerInterface
    */
   protected $serializer;
 
+  /**
+   * {@inheritdoc}
+   */
   protected function setUp() {
     parent::setUp();
 
diff --git a/core/modules/serialization/tests/src/Kernel/MapDataNormalizerTest.php b/core/modules/serialization/tests/src/Kernel/MapDataNormalizerTest.php
index 11e3353..80e05ae 100644
--- a/core/modules/serialization/tests/src/Kernel/MapDataNormalizerTest.php
+++ b/core/modules/serialization/tests/src/Kernel/MapDataNormalizerTest.php
@@ -14,7 +14,6 @@ class MapDataNormalizerTest extends KernelTestBase {
   /**
    * {@inheritdoc}
    */
-
   public static $modules = ['system', 'serialization'];
 
   /**
diff --git a/core/modules/system/tests/modules/entity_test/tests/src/Functional/Rest/EntityTestMapFieldResourceTestBase.php b/core/modules/system/tests/modules/entity_test/tests/src/Functional/Rest/EntityTestMapFieldResourceTestBase.php
index 92a49b7..16bcf4b 100644
--- a/core/modules/system/tests/modules/entity_test/tests/src/Functional/Rest/EntityTestMapFieldResourceTestBase.php
+++ b/core/modules/system/tests/modules/entity_test/tests/src/Functional/Rest/EntityTestMapFieldResourceTestBase.php
@@ -2,7 +2,6 @@
 
 namespace Drupal\Tests\entity_test\Functional\Rest;
 
-use Drupal\entity_test\Entity\EntityTest;
 use Drupal\entity_test\Entity\EntityTestMapField;
 use Drupal\Tests\rest\Functional\BcTimestampNormalizerUnixTestTrait;
 use Drupal\Tests\rest\Functional\EntityResource\EntityResourceTestBase;
@@ -34,6 +33,11 @@
    */
   protected $entity;
 
+  /**
+   * The complex nested value to assign to a @FieldType=map field.
+   *
+   * @var array
+   */
   protected static $mapValue = [
     'key1' => 'value',
     'key2' => 'no, val you',
@@ -133,7 +137,6 @@ protected function getExpectedUnauthorizedAccessMessage($method) {
     return "The 'administer entity_test content' permission is required.";
   }
 
-
   /**
    * {@inheritdoc}
    */