diff --git a/core/modules/big_pipe/tests/src/Unit/Render/BigPipeResponseAttachmentsProcessorTest.php b/core/modules/big_pipe/tests/src/Unit/Render/BigPipeResponseAttachmentsProcessorTest.php
index 0ae2104b6ed75ef09ed489bf4decd9e2380b3251..69eca6473b49a78daa6f658397eb318352ef991b 100644
--- a/core/modules/big_pipe/tests/src/Unit/Render/BigPipeResponseAttachmentsProcessorTest.php
+++ b/core/modules/big_pipe/tests/src/Unit/Render/BigPipeResponseAttachmentsProcessorTest.php
@@ -42,6 +42,9 @@ public function testNonHtmlResponse($response_class): void {
     $big_pipe_response_attachments_processor->processAttachments($non_html_response);
   }
 
+  /**
+   * Provides data to testNonHtmlResponse().
+   */
   public static function nonHtmlResponseProvider() {
     return [
       'AjaxResponse, which implements AttachmentsInterface' => [AjaxResponse::class],
@@ -89,6 +92,9 @@ public function testHtmlResponse(array $attachments): void {
     $this->assertEquals('processed', $processed_big_pipe_response->getContent(), 'Content of returned (processed) response object MUST be changed.');
   }
 
+  /**
+   * Provides data to testHtmlResponse().
+   */
   public static function attachmentsProvider() {
     $typical_cases = [
       'no attachments' => [[]],
diff --git a/core/modules/big_pipe/tests/src/Unit/StackMiddleware/ContentLengthTest.php b/core/modules/big_pipe/tests/src/Unit/StackMiddleware/ContentLengthTest.php
index 3a6090b7afffae2ded5ca4366d273c4a24e8edea..ec0cd6c9a3c537f2f87584ba58b07468e06019e4 100644
--- a/core/modules/big_pipe/tests/src/Unit/StackMiddleware/ContentLengthTest.php
+++ b/core/modules/big_pipe/tests/src/Unit/StackMiddleware/ContentLengthTest.php
@@ -37,6 +37,9 @@ public function testHandle(false|int $expected_header, Response $response): void
     $this->assertSame((string) $expected_header, $response->headers->get('Content-Length'));
   }
 
+  /**
+   * Provides data for testHandle().
+   */
   public static function providerTestSetContentLengthHeader() {
     $response = new Response('Test content', 200);
     $response->headers->set('Content-Length', (string) strlen('Test content'));
diff --git a/core/modules/block/tests/src/Unit/BlockRepositoryTest.php b/core/modules/block/tests/src/Unit/BlockRepositoryTest.php
index 4d36f8aa36ced5f84054d2301b1c2a850af8d2fb..dd1a70b76fc2a3421d6a920eda0037ab3e45da42 100644
--- a/core/modules/block/tests/src/Unit/BlockRepositoryTest.php
+++ b/core/modules/block/tests/src/Unit/BlockRepositoryTest.php
@@ -112,6 +112,9 @@ public function testGetVisibleBlocksPerRegion(array $blocks_config, array $expec
     $this->assertEquals($expected_blocks, $result);
   }
 
+  /**
+   * Provides data to testGetVisibleBlocksPerRegion().
+   */
   public static function providerBlocksConfig() {
     $blocks_config = [
       'block1' => [
diff --git a/core/modules/block/tests/src/Unit/Plugin/DisplayVariant/BlockPageVariantTest.php b/core/modules/block/tests/src/Unit/Plugin/DisplayVariant/BlockPageVariantTest.php
index d9648265184e056026bfe0b92a0d769d1f7de8cb..871af6072fd437519a5ecd48d51b024b1f0ce3b5 100644
--- a/core/modules/block/tests/src/Unit/Plugin/DisplayVariant/BlockPageVariantTest.php
+++ b/core/modules/block/tests/src/Unit/Plugin/DisplayVariant/BlockPageVariantTest.php
@@ -66,6 +66,9 @@ public function setUpDisplayVariant($configuration = [], $definition = []) {
     return new BlockPageVariant($configuration, 'test', $definition, $this->blockRepository, $this->blockViewBuilder, ['config:block_list']);
   }
 
+  /**
+   * Provides data to testBuild().
+   */
   public static function providerBuild() {
     $blocks_config = [
       'block1' => [
diff --git a/core/modules/ckeditor5/tests/src/Unit/HTMLRestrictionsTest.php b/core/modules/ckeditor5/tests/src/Unit/HTMLRestrictionsTest.php
index 49621be87fd7bc8617ea65cf3945ef3cc96743d7..f512c008ceeb79e33e2bd91bc6a905a5df52c3c2 100644
--- a/core/modules/ckeditor5/tests/src/Unit/HTMLRestrictionsTest.php
+++ b/core/modules/ckeditor5/tests/src/Unit/HTMLRestrictionsTest.php
@@ -28,6 +28,9 @@ public function testConstructor(array $elements, ?string $expected_exception_mes
     $this->assertIsArray($restrictions->getAllowedElements(FALSE));
   }
 
+  /**
+   * Provides data to testConstructor().
+   */
   public static function providerConstruct(): \Generator {
     // Fundamental structure.
     yield 'INVALID: list instead of key-value pairs' => [
@@ -167,6 +170,9 @@ public function testCounting(array $elements, bool $expected_is_empty, int $expe
     $this->assertCount($expected_concrete_plus_wildcard_count, $r->getAllowedElements(FALSE));
   }
 
+  /**
+   * Provides data to testCounting().
+   */
   public static function providerCounting(): \Generator {
     yield 'empty' => [
       [],
@@ -257,6 +263,9 @@ public function testConvenienceConstructors($input, array $expected, ?array $exp
     $this->assertSame($expected_raw + $filter_html_additional_expectations, HTMLRestrictions::fromFilterPluginInstance($filter_plugin_instance->reveal())->getAllowedElements(FALSE));
   }
 
+  /**
+   * Provides data to testConvenienceConstructors().
+   */
   public static function providerConvenienceConstructors(): \Generator {
     // All empty cases.
     yield 'empty string' => [
@@ -639,6 +648,9 @@ public function testRepresentations(HTMLRestrictions $restrictions, array $expec
     $this->assertSame($expected_ghs_config, $restrictions->toGeneralHtmlSupportConfig());
   }
 
+  /**
+   * Provides data to testRepresentations().
+   */
   public static function providerRepresentations(): \Generator {
     yield 'empty set' => [
       HTMLRestrictions::emptySet(),
@@ -920,6 +932,9 @@ public function testOperations(HTMLRestrictions $a, HTMLRestrictions $b, $expect
     $this->assertEquals($expected_union, $a->merge($b));
   }
 
+  /**
+   * Provides data to testOperations().
+   */
   public static function providerOperands(): \Generator {
     // Empty set operand cases.
     yield 'any set + empty set' => [
@@ -1678,6 +1693,9 @@ public function testSubsets(HTMLRestrictions $input, HTMLRestrictions $expected_
     $this->assertEquals($expected_extracted_plain_tags_subset, $input->extractPlainTagsSubset());
   }
 
+  /**
+   * Provides data to testSubsets().
+   */
   public static function providerSubsets(): \Generator {
     yield 'empty set' => [
       new HTMLRestrictions([]),
diff --git a/core/modules/comment/tests/src/Unit/CommentLinkBuilderTest.php b/core/modules/comment/tests/src/Unit/CommentLinkBuilderTest.php
index d00c44595dac226e345e0e2e50dc873baf2272cc..76c3578a41a0606d1dd294250c3433da9be3ace5 100644
--- a/core/modules/comment/tests/src/Unit/CommentLinkBuilderTest.php
+++ b/core/modules/comment/tests/src/Unit/CommentLinkBuilderTest.php
@@ -333,6 +333,9 @@ protected function getMockNode($has_field, $comment_status, $form_location, $com
 
 if (!function_exists('history_read')) {
 
+  /**
+   * Gets a timestamp for the current user's last view of a specified node.
+   */
   function history_read($nid) {
     return 0;
   }
diff --git a/core/modules/field/tests/src/Unit/FieldConfigEntityUnitTest.php b/core/modules/field/tests/src/Unit/FieldConfigEntityUnitTest.php
index 07f2b29dd663627abfdf92b601cfcc2e8b2ae21b..a638add1049ed7b9020226fe7d5250c17b343fc0 100644
--- a/core/modules/field/tests/src/Unit/FieldConfigEntityUnitTest.php
+++ b/core/modules/field/tests/src/Unit/FieldConfigEntityUnitTest.php
@@ -303,10 +303,16 @@ public function testGetType(): void {
  */
 class DependencyFieldItem {
 
+  /**
+   * Gets the dependencies for this field item.
+   */
   public static function calculateDependencies(FieldDefinitionInterface $definition) {
     return ['module' => ['test_module3']];
   }
 
+  /**
+   * Informs the entity that entities it depends on will be deleted.
+   */
   public static function onDependencyRemoval($field_config, $dependencies) {
   }
 
diff --git a/core/modules/file/tests/src/Unit/Plugin/migrate/process/d6/FileUriTest.php b/core/modules/file/tests/src/Unit/Plugin/migrate/process/d6/FileUriTest.php
index ef3dfb4767e1026f1e2abfc3764ab794a45da7f8..6fd395a23ef6ff360185bb769b7635d294886a3d 100644
--- a/core/modules/file/tests/src/Unit/Plugin/migrate/process/d6/FileUriTest.php
+++ b/core/modules/file/tests/src/Unit/Plugin/migrate/process/d6/FileUriTest.php
@@ -24,6 +24,9 @@ class FileUriTest extends MigrateTestCase {
     'id' => 'test',
   ];
 
+  /**
+   * Tests with a public scheme.
+   */
   public function testPublic(): void {
     $value = [
       'sites/default/files/foo.jpg',
@@ -34,6 +37,9 @@ public function testPublic(): void {
     $this->assertEquals('public://foo.jpg', $this->doTransform($value));
   }
 
+  /**
+   * Tests with a base path that is not known.
+   */
   public function testPublicUnknownBasePath(): void {
     $value = [
       '/path/to/public/files/foo.jpg',
@@ -44,6 +50,9 @@ public function testPublicUnknownBasePath(): void {
     $this->assertEquals('public://path/to/public/files/foo.jpg', $this->doTransform($value));
   }
 
+  /**
+   * Tests with a private scheme.
+   */
   public function testPrivate(): void {
     $value = [
       'sites/default/files/baz.gif',
@@ -54,6 +63,9 @@ public function testPrivate(): void {
     $this->assertEquals('private://baz.gif', $this->doTransform($value));
   }
 
+  /**
+   * Tests with a private base path that is not known.
+   */
   public function testPrivateUnknownBasePath(): void {
     $value = [
       '/path/to/private/files/baz.gif',
@@ -64,6 +76,9 @@ public function testPrivateUnknownBasePath(): void {
     $this->assertEquals('private://path/to/private/files/baz.gif', $this->doTransform($value));
   }
 
+  /**
+   * Tests the temporary scheme.
+   */
   public function testTemporary(): void {
     $value = [
       '/tmp/bar.png',
@@ -74,6 +89,9 @@ public function testTemporary(): void {
     $this->assertEquals('temporary://bar.png', $this->doTransform($value));
   }
 
+  /**
+   * Performs the transform process.
+   */
   protected function doTransform(array $value) {
     $executable = new MigrateExecutable($this->getMigration());
     $row = new Row();
diff --git a/core/modules/filter/tests/src/Unit/FilterUninstallValidatorTest.php b/core/modules/filter/tests/src/Unit/FilterUninstallValidatorTest.php
index e79c6d23b1bc880d5b4f927edbfb1211762298a1..25d31c500c6ef6e75ccd6fd76c15df506a82dc1a 100644
--- a/core/modules/filter/tests/src/Unit/FilterUninstallValidatorTest.php
+++ b/core/modules/filter/tests/src/Unit/FilterUninstallValidatorTest.php
@@ -171,6 +171,9 @@ public function testValidateNoMatchingFormats(): void {
  */
 class FilterBaseTestableClass extends FilterBase {
 
+  /**
+   * {@inheritdoc}
+   */
   public function process($text, $langcode) {
     return new FilterProcessResult();
   }
diff --git a/core/modules/language/tests/src/Unit/ContentLanguageSettingsUnitTest.php b/core/modules/language/tests/src/Unit/ContentLanguageSettingsUnitTest.php
index cf7388e7dccf3d3a7faa76945ab73c0680600e20..86236f3a47a5981d3459a4ff5d94c384348ad5a4 100644
--- a/core/modules/language/tests/src/Unit/ContentLanguageSettingsUnitTest.php
+++ b/core/modules/language/tests/src/Unit/ContentLanguageSettingsUnitTest.php
@@ -151,6 +151,9 @@ public function testDefaultLangcode(ContentLanguageSettings $config, $expected):
     $this->assertSame($expected, $config->getDefaultLangcode());
   }
 
+  /**
+   * Provides data to testDefaultLangcode().
+   */
   public static function providerDefaultLangcode() {
     $langcode = Random::machineName();
     $config = new ContentLanguageSettings([
@@ -180,6 +183,9 @@ public function testLanguageAlterable(ContentLanguageSettings $config, $expected
     $this->assertSame($expected, $config->isLanguageAlterable());
   }
 
+  /**
+   * Provides data to testLanguageAlterable().
+   */
   public static function providerLanguageAlterable() {
     $alterableConfig = new ContentLanguageSettings([
       'target_entity_type_id' => 'test_entity_type',
@@ -214,6 +220,9 @@ public function testIsDefaultConfiguration(ContentLanguageSettings $config, $exp
     $this->assertSame($expected, $config->isDefaultConfiguration());
   }
 
+  /**
+   * Provides data to testIsDefaultConfiguration().
+   */
   public static function providerIsDefaultConfiguration() {
     $alteredLanguage = new ContentLanguageSettings([
       'target_entity_type_id' => 'test_entity_type',
@@ -281,6 +290,9 @@ public function testLoadByEntityTypeBundle($config_id, ?ContentLanguageSettings
     $this->assertSame($expected_language_alterable, $config->isLanguageAlterable());
   }
 
+  /**
+   * Provides data to testLoadByEntityTypeBundle().
+   */
   public static function providerLoadByEntityTypeBundle() {
     $alteredLanguage = new ContentLanguageSettings([
       'target_entity_type_id' => 'test_entity_type',
diff --git a/core/modules/language/tests/src/Unit/LanguageNegotiationUrlTest.php b/core/modules/language/tests/src/Unit/LanguageNegotiationUrlTest.php
index 0784b457a125ac2bcbcb4d916f21c41268719b91..8fb765cdcaad92d648ac5acc99f5f55bb8b8e9c9 100644
--- a/core/modules/language/tests/src/Unit/LanguageNegotiationUrlTest.php
+++ b/core/modules/language/tests/src/Unit/LanguageNegotiationUrlTest.php
@@ -345,6 +345,9 @@ public static function providerTestDomain() {
 
 if (!function_exists('base_path')) {
 
+  /**
+   * Returns the base path.
+   */
   function base_path() {
     return '/';
   }
diff --git a/core/modules/locale/tests/src/Unit/LocaleBulkDeprecationTest.php b/core/modules/locale/tests/src/Unit/LocaleBulkDeprecationTest.php
index efa52a8ec67e54c54e87d26b7de4ff76121de40f..176ffa13292b86271aa4443de134b9e933d46aa5 100644
--- a/core/modules/locale/tests/src/Unit/LocaleBulkDeprecationTest.php
+++ b/core/modules/locale/tests/src/Unit/LocaleBulkDeprecationTest.php
@@ -14,6 +14,9 @@
  */
 class LocaleBulkDeprecationTest extends UnitTestCase {
 
+  /**
+   * {@inheritdoc}
+   */
   protected function setUp(): void {
     parent::setUp();
 
diff --git a/core/modules/migrate/tests/src/Unit/Plugin/migrate/destination/EntityContentBaseTest.php b/core/modules/migrate/tests/src/Unit/Plugin/migrate/destination/EntityContentBaseTest.php
index 6b18a1bacb830dff395b6c63e8affa12e263d2d0..1cabbebdde6f088d1ae8918bf3830969f0988761 100644
--- a/core/modules/migrate/tests/src/Unit/Plugin/migrate/destination/EntityContentBaseTest.php
+++ b/core/modules/migrate/tests/src/Unit/Plugin/migrate/destination/EntityContentBaseTest.php
@@ -122,14 +122,23 @@ class EntityTestDestination extends EntityContentBase {
    */
   private $entity = NULL;
 
+  /**
+   * Sets the test entity.
+   */
   public function setEntity($entity): void {
     $this->entity = $entity;
   }
 
+  /**
+   * Gets the test entity.
+   */
   protected function getEntity(Row $row, array $old_destination_id_values) {
     return $this->entity;
   }
 
+  /**
+   * Gets the test entity ID.
+   */
   public static function getEntityTypeId($plugin_id) {
     return 'foo';
   }
diff --git a/core/modules/migrate/tests/src/Unit/Plugin/migrate/destination/EntityRevisionTest.php b/core/modules/migrate/tests/src/Unit/Plugin/migrate/destination/EntityRevisionTest.php
index 610f5dbb5bf5f75618a43da0a4b4e5fff6947381..1dde373b8851d90cfa47b49c60704129c8a45f98 100644
--- a/core/modules/migrate/tests/src/Unit/Plugin/migrate/destination/EntityRevisionTest.php
+++ b/core/modules/migrate/tests/src/Unit/Plugin/migrate/destination/EntityRevisionTest.php
@@ -110,14 +110,23 @@ class EntityRevisionTestDestination extends EntityRevision {
    */
   private $entity = NULL;
 
+  /**
+   * Sets the test entity.
+   */
   public function setEntity($entity): void {
     $this->entity = $entity;
   }
 
+  /**
+   * Gets the test entity.
+   */
   protected function getEntity(Row $row, array $old_destination_id_values) {
     return $this->entity;
   }
 
+  /**
+   * Gets the test entity ID.
+   */
   public static function getEntityTypeId($plugin_id) {
     return 'foo';
   }
diff --git a/core/modules/migrate/tests/src/Unit/Plugin/migrate/destination/EntityTestBase.php b/core/modules/migrate/tests/src/Unit/Plugin/migrate/destination/EntityTestBase.php
index 4176c39350243d34c0979688c00c44c3d3d85a40..ff185911cccba5c14007da3b85ea69cd04e23dd1 100644
--- a/core/modules/migrate/tests/src/Unit/Plugin/migrate/destination/EntityTestBase.php
+++ b/core/modules/migrate/tests/src/Unit/Plugin/migrate/destination/EntityTestBase.php
@@ -59,14 +59,23 @@ protected function setUp(): void {
  */
 class BaseFieldDefinitionTest extends BaseFieldDefinition {
 
+  /**
+   * {@inheritdoc}
+   */
   public static function create($type) {
     return new static([]);
   }
 
+  /**
+   * {@inheritdoc}
+   */
   public function getSettings() {
     return [];
   }
 
+  /**
+   * {@inheritdoc}
+   */
   public function getType() {
     return 'integer';
   }
diff --git a/core/modules/migrate/tests/src/Unit/TestSqlIdMap.php b/core/modules/migrate/tests/src/Unit/TestSqlIdMap.php
index 0ddee30853935959624cf9848145a239bb713266..296d615f6e2d9c1829cce19437a22b21124bb1ab 100644
--- a/core/modules/migrate/tests/src/Unit/TestSqlIdMap.php
+++ b/core/modules/migrate/tests/src/Unit/TestSqlIdMap.php
@@ -82,7 +82,7 @@ protected function getFieldSchema(array $id_definition) {
   /**
    * {@inheritdoc}
    */
-  // phpcs:ignore Generic.CodeAnalysis.UselessOverridingMethod
+  // phpcs:ignore Generic.CodeAnalysis.UselessOverridingMethod, Drupal.Commenting.FunctionComment.Missing
   public function ensureTables() {
     parent::ensureTables();
   }
diff --git a/core/modules/migrate/tests/src/Unit/destination/PerComponentEntityDisplayTest.php b/core/modules/migrate/tests/src/Unit/destination/PerComponentEntityDisplayTest.php
index 0c2b729e8b662803da050295c6223b8e53ddeb81..bac47cde2f20f389aba92cd926bd7788cecb7594 100644
--- a/core/modules/migrate/tests/src/Unit/destination/PerComponentEntityDisplayTest.php
+++ b/core/modules/migrate/tests/src/Unit/destination/PerComponentEntityDisplayTest.php
@@ -71,11 +71,17 @@ public function __construct($entity) {
     $this->entity = $entity;
   }
 
+  /**
+   * Gets the test entity.
+   */
   protected function getEntity($entity_type, $bundle, $view_mode) {
     $this->testValues = func_get_args();
     return $this->entity;
   }
 
+  /**
+   * Gets the test values.
+   */
   public function getTestValues() {
     return $this->testValues;
   }
diff --git a/core/modules/migrate/tests/src/Unit/destination/PerComponentEntityFormDisplayTest.php b/core/modules/migrate/tests/src/Unit/destination/PerComponentEntityFormDisplayTest.php
index 0ce3f69e6bb328ef4615d67005b1c7debc4c9c37..774ba999baf62dc95d27cfd50ed3d1e7eadd7a63 100644
--- a/core/modules/migrate/tests/src/Unit/destination/PerComponentEntityFormDisplayTest.php
+++ b/core/modules/migrate/tests/src/Unit/destination/PerComponentEntityFormDisplayTest.php
@@ -71,11 +71,17 @@ public function __construct($entity) {
     $this->entity = $entity;
   }
 
+  /**
+   * Gets the test entity.
+   */
   protected function getEntity($entity_type, $bundle, $form_mode) {
     $this->testValues = func_get_args();
     return $this->entity;
   }
 
+  /**
+   * Gets the test values.
+   */
   public function getTestValues() {
     return $this->testValues;
   }
diff --git a/core/modules/mysql/tests/src/Unit/InstallTasksTest.php b/core/modules/mysql/tests/src/Unit/InstallTasksTest.php
index a50a6f010c76fc42a2d50faef81a41e36ddcf34f..90305518bee27b34ce9e2bdd3238433911ddb433 100644
--- a/core/modules/mysql/tests/src/Unit/InstallTasksTest.php
+++ b/core/modules/mysql/tests/src/Unit/InstallTasksTest.php
@@ -55,14 +55,23 @@ public function __construct(Connection $connection) {
         $this->connection = $connection;
       }
 
+      /**
+       * {@inheritdoc}
+       */
       protected function isConnectionActive() {
         return TRUE;
       }
 
+      /**
+       * {@inheritdoc}
+       */
       protected function getConnection() {
         return $this->connection;
       }
 
+      /**
+       * {@inheritdoc}
+       */
       protected function t($string, array $args = [], array $options = []) {
         return $string;
       }
@@ -79,14 +88,23 @@ protected function t($string, array $args = [], array $options = []) {
   private function createTasksNoConnection(): Tasks {
     return new class() extends Tasks {
 
+      /**
+       * {@inheritdoc}
+       */
       protected function isConnectionActive() {
         return FALSE;
       }
 
+      /**
+       * {@inheritdoc}
+       */
       protected function getConnection() {
         return NULL;
       }
 
+      /**
+       * {@inheritdoc}
+       */
       protected function t($string, array $args = [], array $options = []) {
         return $string;
       }
diff --git a/core/modules/package_manager/tests/src/Unit/LoggingBeginnerTest.php b/core/modules/package_manager/tests/src/Unit/LoggingBeginnerTest.php
index af84befb7dab63302967039cedd69d59484c29b2..b54e663179a44b7f64475225ded1490dbf2eaa2f 100644
--- a/core/modules/package_manager/tests/src/Unit/LoggingBeginnerTest.php
+++ b/core/modules/package_manager/tests/src/Unit/LoggingBeginnerTest.php
@@ -18,6 +18,9 @@
  */
 class LoggingBeginnerTest extends UnitTestCase {
 
+  /**
+   * Tests the output of LoggingBeginner().
+   */
   public function testDecoratedBeginnerIsCalled(): void {
     $decorated = $this->createMock(BeginnerInterface::class);
 
diff --git a/core/modules/package_manager/tests/src/Unit/LoggingCommitterTest.php b/core/modules/package_manager/tests/src/Unit/LoggingCommitterTest.php
index 3d6ab55de0cf5c26252f35fd84852f8ab14179bb..83c19a1b8b66f7484bd3f47256c53774764dc81c 100644
--- a/core/modules/package_manager/tests/src/Unit/LoggingCommitterTest.php
+++ b/core/modules/package_manager/tests/src/Unit/LoggingCommitterTest.php
@@ -18,6 +18,9 @@
  */
 class LoggingCommitterTest extends UnitTestCase {
 
+  /**
+   * Tests the output of LoggingCommitter().
+   */
   public function testDecoratedCommitterIsCalled(): void {
     $decorated = $this->createMock(CommitterInterface::class);
 
diff --git a/core/modules/package_manager/tests/src/Unit/LoggingStagerTest.php b/core/modules/package_manager/tests/src/Unit/LoggingStagerTest.php
index f21577c348d398415728d603fd5141ce2a98fe03..a7e6c050e1738ab6b24106e4f583190aaa579019 100644
--- a/core/modules/package_manager/tests/src/Unit/LoggingStagerTest.php
+++ b/core/modules/package_manager/tests/src/Unit/LoggingStagerTest.php
@@ -18,6 +18,9 @@
  */
 class LoggingStagerTest extends UnitTestCase {
 
+  /**
+   * Tests LoggingStager().
+   */
   public function testDecoratedStagerIsCalled(): void {
     $decorated = $this->createMock(StagerInterface::class);
 
diff --git a/core/modules/rest/tests/src/Unit/EventSubscriber/ResourceResponseSubscriberTest.php b/core/modules/rest/tests/src/Unit/EventSubscriber/ResourceResponseSubscriberTest.php
index 5b1c0c400b545ad101cf1b27450b64f2e11f11f3..7e0740473736ed89dcd05579c19bc4c88e19f29f 100644
--- a/core/modules/rest/tests/src/Unit/EventSubscriber/ResourceResponseSubscriberTest.php
+++ b/core/modules/rest/tests/src/Unit/EventSubscriber/ResourceResponseSubscriberTest.php
@@ -53,6 +53,9 @@ public function testSerialization($data, $expected_response = FALSE): void {
     $this->assertEquals($expected_response !== FALSE ? $expected_response : Json::encode($data), $event->getResponse()->getContent());
   }
 
+  /**
+   * Provides data to testSerialization().
+   */
   public static function providerTestSerialization() {
     return [
       // The default data for \Drupal\rest\ResourceResponse.
diff --git a/core/modules/search/tests/src/Unit/SearchPageRepositoryTest.php b/core/modules/search/tests/src/Unit/SearchPageRepositoryTest.php
index ce67ed1e00567518bdec6901b5cd024b5b9107a1..fdc9754f3bd1335e4cb8c956e69f17d464cfdc85 100644
--- a/core/modules/search/tests/src/Unit/SearchPageRepositoryTest.php
+++ b/core/modules/search/tests/src/Unit/SearchPageRepositoryTest.php
@@ -321,6 +321,9 @@ public function __construct(array $values) {
     }
   }
 
+  /**
+   * {@inheritdoc}
+   */
   public function label($langcode = NULL) {
     return $this->label;
   }
diff --git a/core/modules/serialization/tests/src/Unit/Encoder/XmlEncoderTest.php b/core/modules/serialization/tests/src/Unit/Encoder/XmlEncoderTest.php
index e4da1fbde1fed1899ca3644f7873bf073c4fbafb..99130000b4040badd6aa4b3eef86c845b93d2c19 100644
--- a/core/modules/serialization/tests/src/Unit/Encoder/XmlEncoderTest.php
+++ b/core/modules/serialization/tests/src/Unit/Encoder/XmlEncoderTest.php
@@ -108,6 +108,9 @@ public function testDefaultEncoderHasSerializer(): void {
  */
 class TestObject {
 
+  /**
+   * Return the characters "A".
+   */
   public function getA() {
     return 'A';
   }
diff --git a/core/modules/serialization/tests/src/Unit/Normalizer/DateTimeIso8601NormalizerTest.php b/core/modules/serialization/tests/src/Unit/Normalizer/DateTimeIso8601NormalizerTest.php
index 4a805e19d6b343a0b7d5782bdecdbe775811cb73..9c6d8a52f5c869c16490a9c9d060f8993e027bc2 100644
--- a/core/modules/serialization/tests/src/Unit/Normalizer/DateTimeIso8601NormalizerTest.php
+++ b/core/modules/serialization/tests/src/Unit/Normalizer/DateTimeIso8601NormalizerTest.php
@@ -307,6 +307,9 @@ public static function jsonSchemaDataProvider(): array {
  */
 class DateTimeIso8601NormalizerTestDrupalDateTime extends DrupalDateTime {
 
+  /**
+   * Sets the timezone.
+   */
   public function setTimezone(\DateTimeZone $timezone) {
     parent::setTimezone($timezone);
   }
diff --git a/core/modules/serialization/tests/src/Unit/Normalizer/DateTimeNormalizerTest.php b/core/modules/serialization/tests/src/Unit/Normalizer/DateTimeNormalizerTest.php
index 3527c5ef6ffdaaa98b898d63cbf59dacde1947b9..3082742e4a47ee8a9b7bec24b706b1ca9d700e9d 100644
--- a/core/modules/serialization/tests/src/Unit/Normalizer/DateTimeNormalizerTest.php
+++ b/core/modules/serialization/tests/src/Unit/Normalizer/DateTimeNormalizerTest.php
@@ -232,6 +232,9 @@ public static function jsonSchemaDataProvider(): array {
  */
 class DateTimeNormalizerTestDrupalDateTime extends DrupalDateTime {
 
+  /**
+   * Sets the timezone.
+   */
   public function setTimezone(\DateTimeZone $timezone) {
     parent::setTimezone($timezone);
   }
diff --git a/core/modules/serialization/tests/src/Unit/Normalizer/EntityReferenceFieldItemNormalizerTest.php b/core/modules/serialization/tests/src/Unit/Normalizer/EntityReferenceFieldItemNormalizerTest.php
index 905598fea7869e5d5ac1cdb2b4cadd87feed4356..02ee2585da874a4309cc2fb68fe7139f466be28d 100644
--- a/core/modules/serialization/tests/src/Unit/Normalizer/EntityReferenceFieldItemNormalizerTest.php
+++ b/core/modules/serialization/tests/src/Unit/Normalizer/EntityReferenceFieldItemNormalizerTest.php
@@ -169,6 +169,9 @@ public function testNormalize(): void {
     $this->assertSame($expected, $normalized);
   }
 
+  /**
+   * Tests normalizing with an entity reference field.
+   */
   public function testNormalizeWithNewEntityReference(): void {
     $test_url = '/test/100';
 
diff --git a/core/modules/serialization/tests/src/Unit/Normalizer/TimestampNormalizerTest.php b/core/modules/serialization/tests/src/Unit/Normalizer/TimestampNormalizerTest.php
index e0e4c991c470f01d37667c2f0d2c74a04acfab7e..60f6db35f7cec0c7255eea10e49ffa24edc23fe4 100644
--- a/core/modules/serialization/tests/src/Unit/Normalizer/TimestampNormalizerTest.php
+++ b/core/modules/serialization/tests/src/Unit/Normalizer/TimestampNormalizerTest.php
@@ -172,6 +172,9 @@ public static function jsonSchemaDataProvider(): array {
  */
 class TimestampNormalizerTestDrupalDateTime extends DrupalDateTime {
 
+  /**
+   * Sets the timezone.
+   */
   public function setTimezone(\DateTimeZone $timezone) {
     parent::setTimezone($timezone);
   }
diff --git a/core/modules/system/tests/src/Unit/Breadcrumbs/PathBasedBreadcrumbBuilderTest.php b/core/modules/system/tests/src/Unit/Breadcrumbs/PathBasedBreadcrumbBuilderTest.php
index e3745d48775533a9366f8b5ad55c17f3ada440a6..58a2a29e162c605851ec2cd846bd56b8908cf414 100644
--- a/core/modules/system/tests/src/Unit/Breadcrumbs/PathBasedBreadcrumbBuilderTest.php
+++ b/core/modules/system/tests/src/Unit/Breadcrumbs/PathBasedBreadcrumbBuilderTest.php
@@ -419,6 +419,9 @@ public function setupAccessManagerToAllow(): void {
       ->willReturn((new AccessResultAllowed())->cachePerPermissions());
   }
 
+  /**
+   * Prepares the mock processInbound() method.
+   */
   protected function setupStubPathProcessor(): void {
     $this->pathProcessor->expects($this->any())
       ->method('processInbound')
@@ -437,11 +440,17 @@ class TestPathBasedBreadcrumbBuilder extends PathBasedBreadcrumbBuilder {
    */
   protected LinkGeneratorInterface $linkGenerator;
 
+  /**
+   * {@inheritdoc}
+   */
   public function setStringTranslation(TranslationInterface $string_translation) {
     $this->stringTranslation = $string_translation;
     return $this;
   }
 
+  /**
+   * Sets the link generator.
+   */
   public function setLinkGenerator(LinkGeneratorInterface $link_generator): void {
     $this->linkGenerator = $link_generator;
   }
diff --git a/core/modules/system/tests/src/Unit/FileTransfer/FileTransferTest.php b/core/modules/system/tests/src/Unit/FileTransfer/FileTransferTest.php
index 2f67aa7a609de7355d232da7b184cf38c96089df..0486dffcc1e4211791912b3271bc38276f5e235e 100644
--- a/core/modules/system/tests/src/Unit/FileTransfer/FileTransferTest.php
+++ b/core/modules/system/tests/src/Unit/FileTransfer/FileTransferTest.php
@@ -27,6 +27,9 @@ protected function setUp(): void {
     $this->testConnection = TestFileTransfer::factory($this->root, []);
   }
 
+  /**
+   * Tests the value returned by __get().
+   */
   public function testFileTransferMagicMethods(): void {
     // Test to ensure __get() preserves public access.
     $this->assertInstanceOf(MockTestConnection::class, $this->testConnection->connection);
diff --git a/core/modules/system/tests/src/Unit/Routing/AdminRouteSubscriberTest.php b/core/modules/system/tests/src/Unit/Routing/AdminRouteSubscriberTest.php
index 7cd8f89c11e08797257b7dc30a917e9302ca3bbf..bbb2c88a8897bde2a243318d8dcae3ee4d276a16 100644
--- a/core/modules/system/tests/src/Unit/Routing/AdminRouteSubscriberTest.php
+++ b/core/modules/system/tests/src/Unit/Routing/AdminRouteSubscriberTest.php
@@ -30,6 +30,9 @@ public function testAlterRoutes(Route $route, $is_admin): void {
     $this->assertSame($is_admin, $route->getOption('_admin_route'));
   }
 
+  /**
+   * Provides data to testAlterRoutes().
+   */
   public static function providerTestAlterRoutes() {
     $data = [];
     $data['non-admin'] = [
diff --git a/core/modules/user/tests/src/Unit/PermissionHandlerTest.php b/core/modules/user/tests/src/Unit/PermissionHandlerTest.php
index 0a46196d1d46ef7b7e9bb250767b08fcabd7c385..c07756add0e1a6b1420a763f065e9e047ba1c387 100644
--- a/core/modules/user/tests/src/Unit/PermissionHandlerTest.php
+++ b/core/modules/user/tests/src/Unit/PermissionHandlerTest.php
@@ -358,12 +358,18 @@ protected function assertPermissions(array $actual_permissions): void {
  */
 class TestPermissionCallbacks {
 
+  /**
+   * Callback that returns a single description.
+   */
   public function singleDescription() {
     return [
       'access_module_a' => 'single_description',
     ];
   }
 
+  /**
+   * Callback that returns the title and description.
+   */
   public function titleDescription() {
     return [
       'access module b' => [
@@ -373,6 +379,9 @@ public function titleDescription() {
     ];
   }
 
+  /**
+   * Callback that returns restricted access.
+   */
   public function titleDescriptionRestrictAccess() {
     return [
       'access_module_c' => [
@@ -383,6 +392,9 @@ public function titleDescriptionRestrictAccess() {
     ];
   }
 
+  /**
+   * Callback that returns the title.
+   */
   public function titleProvider() {
     return [
       'access module a via module b' => [
diff --git a/core/modules/views/tests/src/Unit/Plugin/Block/ViewsBlockTest.php b/core/modules/views/tests/src/Unit/Plugin/Block/ViewsBlockTest.php
index c7dbd103ea10df83980b1a22200b8e88c5298442..75f7305e817306df53cd5cc39d31828decf295f7 100644
--- a/core/modules/views/tests/src/Unit/Plugin/Block/ViewsBlockTest.php
+++ b/core/modules/views/tests/src/Unit/Plugin/Block/ViewsBlockTest.php
@@ -307,6 +307,9 @@ public function testBuildFailed(): void {
 
 if (!function_exists('views_add_contextual_links')) {
 
+  /**
+   * Define method views_add_contextual_links for this test.
+   */
   function views_add_contextual_links(&$render_element, $location, $display_id, ?array $view_element = NULL) {
   }
 
diff --git a/core/modules/views/tests/src/Unit/Plugin/field/FieldPluginBaseTest.php b/core/modules/views/tests/src/Unit/Plugin/field/FieldPluginBaseTest.php
index f2afff8e31dddd03b4c9e75565684c893080b042..489102c07eb9c7fc4e099f0adff11d1ec6b936f1 100644
--- a/core/modules/views/tests/src/Unit/Plugin/field/FieldPluginBaseTest.php
+++ b/core/modules/views/tests/src/Unit/Plugin/field/FieldPluginBaseTest.php
@@ -972,6 +972,9 @@ public function testElementClassesWithTokens(): void {
  */
 class FieldPluginBaseTestField extends FieldPluginBase {
 
+  /**
+   * Set the link generator.
+   */
   public function setLinkGenerator(LinkGeneratorInterface $link_generator): void {
     $this->linkGenerator = $link_generator;
   }
@@ -983,6 +986,9 @@ public function setLinkGenerator(LinkGeneratorInterface $link_generator): void {
 
 if (!function_exists('base_path')) {
 
+  /**
+   * Returns the base path.
+   */
   function base_path() {
     return '/';
   }
diff --git a/core/modules/views/tests/src/Unit/Plugin/field/FieldTest.php b/core/modules/views/tests/src/Unit/Plugin/field/FieldTest.php
index 128a5cefb7cf1528925595f432ba2c8351b24d56..d872bac6cac3834afa5b51b3e4d6068c2ae05e5f 100644
--- a/core/modules/views/tests/src/Unit/Plugin/field/FieldTest.php
+++ b/core/modules/views/tests/src/Unit/Plugin/field/FieldTest.php
@@ -762,6 +762,9 @@ protected function setupLanguageRenderer(EntityField $handler, $definition): voi
  */
 class FieldTestEntityField extends EntityField {
 
+  /**
+   * {@inheritdoc}
+   */
   public function executePrepareItemsByDelta(array $all_values) {
     return $this->prepareItemsByDelta($all_values);
   }
diff --git a/core/modules/views/tests/src/Unit/Plugin/pager/SqlBaseTest.php b/core/modules/views/tests/src/Unit/Plugin/pager/SqlBaseTest.php
index 7dad710f44192b812a2898d6e9bd255aabb83dd3..edd524d3039c6a8406580bf479d10f3db3dc9a49 100644
--- a/core/modules/views/tests/src/Unit/Plugin/pager/SqlBaseTest.php
+++ b/core/modules/views/tests/src/Unit/Plugin/pager/SqlBaseTest.php
@@ -36,6 +36,9 @@ class SqlBaseTest extends UnitTestCase {
    */
   protected $display;
 
+  /**
+   * {@inheritdoc}
+   */
   protected function setUp(): void {
     parent::setUp();
 
diff --git a/core/modules/views/tests/src/Unit/PluginBaseTest.php b/core/modules/views/tests/src/Unit/PluginBaseTest.php
index b0b708a71d8e8352281131466758c7d049fe0c62..a78824176272121a939715ce3c6282910a0d7d08 100644
--- a/core/modules/views/tests/src/Unit/PluginBaseTest.php
+++ b/core/modules/views/tests/src/Unit/PluginBaseTest.php
@@ -290,6 +290,9 @@ public function testFilterByDefinedOptions($storage, $options, $expected_storage
     $this->assertEquals($expected_storage, $storage);
   }
 
+  /**
+   * Provides data to testFilterByDefinedOptions().
+   */
   public static function providerTestFilterByDefinedOptions() {
     $data = [];
 
diff --git a/core/modules/views/tests/src/Unit/Routing/ViewPageControllerTest.php b/core/modules/views/tests/src/Unit/Routing/ViewPageControllerTest.php
index 07e8894e70740d8ca20ffcf94796fa13891646ba..aef3e8c11dd8b6e9df111f6f25905ed6378f70dd 100644
--- a/core/modules/views/tests/src/Unit/Routing/ViewPageControllerTest.php
+++ b/core/modules/views/tests/src/Unit/Routing/ViewPageControllerTest.php
@@ -206,6 +206,9 @@ public function testHandleWithArgumentsOnOverriddenRouteWithUpcasting(): void {
 
 if (!function_exists('views_add_contextual_links')) {
 
+  /**
+   * Define method views_add_contextual_links for this test.
+   */
   function views_add_contextual_links(&$render_element, $location, $display_id, ?array $view_element = NULL) {
   }
 
diff --git a/core/modules/views/tests/src/Unit/ViewsDataTest.php b/core/modules/views/tests/src/Unit/ViewsDataTest.php
index d88891901899873b8e6f34c234364f740fc45020..aec182fb164d73bd0b20d3a9c23c0ed9a679b50b 100644
--- a/core/modules/views/tests/src/Unit/ViewsDataTest.php
+++ b/core/modules/views/tests/src/Unit/ViewsDataTest.php
@@ -649,6 +649,9 @@ public function testGetEmptyKey($key): void {
     $this->viewsData->get($key);
   }
 
+  /**
+   * Provides data to testGetEmptyKey().
+   */
   public static function providerTestGetEmptyKey() {
     return [
       [NULL],
diff --git a/core/modules/views_ui/tests/src/Unit/ViewListBuilderTest.php b/core/modules/views_ui/tests/src/Unit/ViewListBuilderTest.php
index b6a878eb54861520d06a4f3d0830ee302e7887c2..b51d5f1018f19386342005b1f1a0a54c2ef9d4c2 100644
--- a/core/modules/views_ui/tests/src/Unit/ViewListBuilderTest.php
+++ b/core/modules/views_ui/tests/src/Unit/ViewListBuilderTest.php
@@ -202,6 +202,9 @@ public function testBuildRowEntityList(): void {
  */
 class TestViewListBuilder extends ViewListBuilder {
 
+  /**
+   * {@inheritdoc}
+   */
   public function buildOperations(EntityInterface $entity) {
     return [];
   }
diff --git a/core/phpcs.xml.dist b/core/phpcs.xml.dist
index 7d3de555897de5423b0a952c7e53099cb7fb0e02..50039ecc171763ecaefdf1f47de7df424f463c98 100644
--- a/core/phpcs.xml.dist
+++ b/core/phpcs.xml.dist
@@ -70,6 +70,7 @@
     <include-pattern>*/FunctionalJavascript/*</include-pattern>
     <include-pattern>*/Kernel/*</include-pattern>
     <include-pattern>*/Functional/*</include-pattern>
+    <include-pattern>*/Unit/*</include-pattern>
   </rule>
   <rule ref="Drupal.Commenting.FunctionComment.MissingParamType"/>
   <rule ref="Drupal.Commenting.FunctionComment.MissingReturnComment">