diff --git a/core/modules/comment/tests/src/Kernel/Views/CommentUserNameTest.php b/core/modules/comment/tests/src/Kernel/Views/CommentUserNameTest.php
index 80820e96028dcff1db827fcc0d4a1e5c3ee41350..61b21e753c19040468046277dc8a4a332a43c77d 100644
--- a/core/modules/comment/tests/src/Kernel/Views/CommentUserNameTest.php
+++ b/core/modules/comment/tests/src/Kernel/Views/CommentUserNameTest.php
@@ -7,6 +7,7 @@
 use Drupal\comment\Entity\Comment;
 use Drupal\comment\Entity\CommentType;
 use Drupal\Core\Session\AnonymousUserSession;
+use Drupal\Core\StringTranslation\StringTranslationTrait;
 use Drupal\entity_test\Entity\EntityTest;
 use Drupal\Tests\views\Kernel\ViewsKernelTestBase;
 use Drupal\user\Entity\Role;
@@ -21,6 +22,8 @@
  */
 class CommentUserNameTest extends ViewsKernelTestBase {
 
+  use StringTranslationTrait;
+
   /**
    * Admin user.
    *
@@ -83,7 +86,7 @@ protected function setUp($import_test_views = TRUE): void {
 
     $commentType = CommentType::create([
       'id' => 'entity_test_comment',
-      'label' => t('Entity Test Comment'),
+      'label' => $this->t('Entity Test Comment'),
       'target_entity_type_id' => 'entity_test',
     ]);
     $commentType->save();
diff --git a/core/modules/language/tests/src/Kernel/Views/LanguageTestBase.php b/core/modules/language/tests/src/Kernel/Views/LanguageTestBase.php
index 6d526ab7628ed9c5cbaf7d471424db9c8b9dba32..05661ddda360ed7cc0ace7c97b43beac2389153f 100644
--- a/core/modules/language/tests/src/Kernel/Views/LanguageTestBase.php
+++ b/core/modules/language/tests/src/Kernel/Views/LanguageTestBase.php
@@ -4,6 +4,7 @@
 
 namespace Drupal\Tests\language\Kernel\Views;
 
+use Drupal\Core\StringTranslation\StringTranslationTrait;
 use Drupal\language\Entity\ConfigurableLanguage;
 use Drupal\Tests\views\Kernel\ViewsKernelTestBase;
 
@@ -12,6 +13,8 @@
  */
 abstract class LanguageTestBase extends ViewsKernelTestBase {
 
+  use StringTranslationTrait;
+
   /**
    * {@inheritdoc}
    */
@@ -49,8 +52,8 @@ protected function schemaDefinition() {
   protected function viewsData() {
     $data = parent::viewsData();
     $data['views_test_data']['langcode'] = [
-      'title' => t('Langcode'),
-      'help' => t('Langcode'),
+      'title' => $this->t('Langcode'),
+      'help' => $this->t('Langcode'),
       'field' => [
         'id' => 'language',
       ],
diff --git a/core/modules/locale/tests/src/Kernel/LocaleStringIsSafeTest.php b/core/modules/locale/tests/src/Kernel/LocaleStringIsSafeTest.php
index 525aad05495a0c640ffd0801316114d78745cbfd..47311d68bae1e7feb130dfbcb0d61fe791ccfd79 100644
--- a/core/modules/locale/tests/src/Kernel/LocaleStringIsSafeTest.php
+++ b/core/modules/locale/tests/src/Kernel/LocaleStringIsSafeTest.php
@@ -4,6 +4,7 @@
 
 namespace Drupal\Tests\locale\Kernel;
 
+use Drupal\Core\StringTranslation\StringTranslationTrait;
 use Drupal\KernelTests\KernelTestBase;
 
 /**
@@ -13,6 +14,8 @@
  */
 class LocaleStringIsSafeTest extends KernelTestBase {
 
+  use StringTranslationTrait;
+
   /**
    * {@inheritdoc}
    */
@@ -75,7 +78,7 @@ public function testLocalizedTokenizedString(): void {
 
       // Pass the original string to the t() function to get it marked as safe.
       // phpcs:ignore Drupal.Semantics.FunctionT.NotLiteralString
-      $safe_string = t($original_string);
+      $safe_string = $this->t($original_string);
       $rendered_safe_string = \Drupal::theme()->render('locale_test_tokenized', ['content' => $safe_string]);
       // t() function always marks the string as safe so it won't be escaped,
       // and should be the same as the original.
diff --git a/core/modules/migrate/tests/src/Kernel/MigrateEntityContentValidationTest.php b/core/modules/migrate/tests/src/Kernel/MigrateEntityContentValidationTest.php
index 6bc3d633be443e9709707aed31648e16d0b4b252..648f3b6099e7b6018045b6df0671cb9dc6fe4e69 100644
--- a/core/modules/migrate/tests/src/Kernel/MigrateEntityContentValidationTest.php
+++ b/core/modules/migrate/tests/src/Kernel/MigrateEntityContentValidationTest.php
@@ -5,6 +5,7 @@
 namespace Drupal\Tests\migrate\Kernel;
 
 use Drupal\Component\Render\FormattableMarkup;
+use Drupal\Core\StringTranslation\StringTranslationTrait;
 use Drupal\field\Entity\FieldConfig;
 use Drupal\field\Entity\FieldStorageConfig;
 use Drupal\filter\Entity\FilterFormat;
@@ -25,6 +26,8 @@
  */
 class MigrateEntityContentValidationTest extends KernelTestBase {
 
+  use StringTranslationTrait;
+
   /**
    * {@inheritdoc}
    */
@@ -155,7 +158,7 @@ public function test2(): void {
     ]);
     $this->assertSame(sprintf('1: [user]: name=%s||name=%s||mail=Email field is required.', $username_constraint->illegalMessage, new FormattableMarkup($username_constraint->tooLongMessage, ['%name' => $long_username, '%max' => 60])), $this->messages[0], 'First message should have 3 validation errors.');
     // phpcs:ignore Drupal.Semantics.FunctionT.NotLiteralString
-    $this->assertSame(sprintf('1: [user]: name=%s||name=%s||mail=Email field is required.', $username_constraint->illegalMessage, t($username_constraint->tooLongMessage, ['%name' => $long_username, '%max' => 60])), $this->messages[0], 'First message should have 3 validation errors.');
+    $this->assertSame(sprintf('1: [user]: name=%s||name=%s||mail=Email field is required.', $username_constraint->illegalMessage, $this->t($username_constraint->tooLongMessage, ['%name' => $long_username, '%max' => 60])), $this->messages[0], 'First message should have 3 validation errors.');
     $this->assertSame(sprintf('2: [user]: name=%s||mail=Email field is required.', $username_constraint->illegalMessage), $this->messages[1], 'Second message should have 2 validation errors.');
     $this->assertSame(sprintf('3: [user]: name=%s||mail=Email field is required.', $username_constraint->illegalMessage), $this->messages[2], 'Third message should have 2 validation errors.');
     $this->assertArrayNotHasKey(3, $this->messages, 'Fourth message should not exist.');
diff --git a/core/modules/package_manager/tests/src/Kernel/AllowedScaffoldPackagesValidatorTest.php b/core/modules/package_manager/tests/src/Kernel/AllowedScaffoldPackagesValidatorTest.php
index f7ebc28da1d7a09c0e0180fa6eda822f6c17947e..bf064f4e2bf1fedc6e4814bf4aa5b039264c89ba 100644
--- a/core/modules/package_manager/tests/src/Kernel/AllowedScaffoldPackagesValidatorTest.php
+++ b/core/modules/package_manager/tests/src/Kernel/AllowedScaffoldPackagesValidatorTest.php
@@ -4,6 +4,7 @@
 
 namespace Drupal\Tests\package_manager\Kernel;
 
+use Drupal\Core\StringTranslation\StringTranslationTrait;
 use Drupal\fixture_manipulator\ActiveFixtureManipulator;
 use Drupal\package_manager\Event\PreApplyEvent;
 use Drupal\package_manager\Event\PreCreateEvent;
@@ -16,6 +17,8 @@
  */
 class AllowedScaffoldPackagesValidatorTest extends PackageManagerKernelTestBase {
 
+  use StringTranslationTrait;
+
   /**
    * Tests that the allowed-packages setting is validated during pre-create.
    */
@@ -29,10 +32,10 @@ public function testPreCreate(): void {
 
     $result = ValidationResult::createError(
       [
-        t("drupal/dummy_scaffolding"),
-        t("drupal/dummy_scaffolding_2"),
+        $this->t("drupal/dummy_scaffolding"),
+        $this->t("drupal/dummy_scaffolding_2"),
       ],
-      t('Any packages other than the implicitly allowed packages are not allowed to scaffold files. See <a href="https://www.drupal.org/docs/develop/using-composer/using-drupals-composer-scaffold">the scaffold documentation</a> for more information.')
+      $this->t('Any packages other than the implicitly allowed packages are not allowed to scaffold files. See <a href="https://www.drupal.org/docs/develop/using-composer/using-drupals-composer-scaffold">the scaffold documentation</a> for more information.')
     );
     $this->assertStatusCheckResults([$result]);
     $this->assertResults([$result], PreCreateEvent::class);
@@ -51,9 +54,9 @@ public function testPreApply(): void {
 
     $result = ValidationResult::createError(
       [
-        t("drupal/dummy_scaffolding"),
+        $this->t("drupal/dummy_scaffolding"),
       ],
-      t('Any packages other than the implicitly allowed packages are not allowed to scaffold files. See <a href="https://www.drupal.org/docs/develop/using-composer/using-drupals-composer-scaffold">the scaffold documentation</a> for more information.')
+      $this->t('Any packages other than the implicitly allowed packages are not allowed to scaffold files. See <a href="https://www.drupal.org/docs/develop/using-composer/using-drupals-composer-scaffold">the scaffold documentation</a> for more information.')
     );
     $this->assertResults([$result], PreApplyEvent::class);
   }
diff --git a/core/modules/package_manager/tests/src/Kernel/BaseRequirementsFulfilledValidatorTest.php b/core/modules/package_manager/tests/src/Kernel/BaseRequirementsFulfilledValidatorTest.php
index 56c8984388b3d482dc72167d9fb46be296eb34a5..06afcf8aeaffb2462d4205b14ac4d7e7478f02fa 100644
--- a/core/modules/package_manager/tests/src/Kernel/BaseRequirementsFulfilledValidatorTest.php
+++ b/core/modules/package_manager/tests/src/Kernel/BaseRequirementsFulfilledValidatorTest.php
@@ -4,6 +4,7 @@
 
 namespace Drupal\Tests\package_manager\Kernel;
 
+use Drupal\Core\StringTranslation\StringTranslationTrait;
 use Drupal\package_manager\Event\PreApplyEvent;
 use Drupal\package_manager\Event\PreCreateEvent;
 use Drupal\package_manager\Event\PreOperationStageEvent;
@@ -23,6 +24,7 @@
 class BaseRequirementsFulfilledValidatorTest extends PackageManagerKernelTestBase implements EventSubscriberInterface {
 
   use BaseRequirementValidatorTrait;
+  use StringTranslationTrait;
 
   /**
    * The event class to throw to an error for.
@@ -37,7 +39,7 @@ class BaseRequirementsFulfilledValidatorTest extends PackageManagerKernelTestBas
   public function validate(PreOperationStageEvent $event): void {
     if (get_class($event) === $this->eventClass) {
       $event->addError([
-        t('This will not stand!'),
+        $this->t('This will not stand!'),
       ]);
     }
   }
@@ -81,7 +83,7 @@ public function testBaseRequirement(string $event_class): void {
     $this->assertEventPropagationStopped($event_class, [$validator, 'validate']);
 
     $result = ValidationResult::createError([
-      t('This will not stand!'),
+      $this->t('This will not stand!'),
     ]);
 
     if ($event_class === StatusCheckEvent::class) {
diff --git a/core/modules/package_manager/tests/src/Kernel/ComposerMinimumStabilityValidatorTest.php b/core/modules/package_manager/tests/src/Kernel/ComposerMinimumStabilityValidatorTest.php
index ce6c4a60a4b8ac6e6c90230d6abce662aa600090..0e4a1eab9a6175cfc7c7cb88456055dd5233cbc3 100644
--- a/core/modules/package_manager/tests/src/Kernel/ComposerMinimumStabilityValidatorTest.php
+++ b/core/modules/package_manager/tests/src/Kernel/ComposerMinimumStabilityValidatorTest.php
@@ -4,6 +4,7 @@
 
 namespace Drupal\Tests\package_manager\Kernel;
 
+use Drupal\Core\StringTranslation\StringTranslationTrait;
 use Drupal\package_manager\Exception\StageEventException;
 use Drupal\package_manager\ValidationResult;
 
@@ -14,6 +15,8 @@
  */
 class ComposerMinimumStabilityValidatorTest extends PackageManagerKernelTestBase {
 
+  use StringTranslationTrait;
+
   /**
    * Tests error if requested version is less stable than the minimum: stable.
    */
@@ -21,7 +24,7 @@ public function testPreRequireEvent(): void {
     $stage = $this->createStage();
     $stage->create();
     $result = ValidationResult::createError([
-      t("<code>drupal/core</code>'s requested version 9.8.1-beta1 is less stable (beta) than the minimum stability (stable) required in <PROJECT_ROOT>/composer.json."),
+      $this->t("<code>drupal/core</code>'s requested version 9.8.1-beta1 is less stable (beta) than the minimum stability (stable) required in <PROJECT_ROOT>/composer.json."),
     ]);
     try {
       $stage->require(['drupal/core:9.8.1-beta1']);
@@ -40,7 +43,7 @@ public function testPreRequireEvent(): void {
     // Dev packages are also checked.
     $stage->create();
     $result = ValidationResult::createError([
-      t("<code>drupal/core-dev</code>'s requested version 9.8.x-dev is less stable (dev) than the minimum stability (stable) required in <PROJECT_ROOT>/composer.json."),
+      $this->t("<code>drupal/core-dev</code>'s requested version 9.8.x-dev is less stable (dev) than the minimum stability (stable) required in <PROJECT_ROOT>/composer.json."),
     ]);
     try {
       $stage->require([], ['drupal/core-dev:9.8.x-dev']);
diff --git a/core/modules/package_manager/tests/src/Kernel/ComposerPatchesValidatorTest.php b/core/modules/package_manager/tests/src/Kernel/ComposerPatchesValidatorTest.php
index 4d1e72fbea04b031a9e1487724a5f737de427ab8..27ce47ab37331d49297a50a275a321c4b3ff9f1d 100644
--- a/core/modules/package_manager/tests/src/Kernel/ComposerPatchesValidatorTest.php
+++ b/core/modules/package_manager/tests/src/Kernel/ComposerPatchesValidatorTest.php
@@ -4,6 +4,7 @@
 
 namespace Drupal\Tests\package_manager\Kernel;
 
+use Drupal\Core\StringTranslation\StringTranslationTrait;
 use Drupal\Core\Url;
 use Drupal\fixture_manipulator\ActiveFixtureManipulator;
 use Drupal\package_manager\Event\PreCreateEvent;
@@ -18,6 +19,8 @@
  */
 class ComposerPatchesValidatorTest extends PackageManagerKernelTestBase {
 
+  use StringTranslationTrait;
+
   const ABSENT = 0;
   const CONFIG_ALLOWED_PLUGIN = 1;
   const EXTRA_EXIT_ON_PATCH_FAILURE = 2;
@@ -283,7 +286,7 @@ public function testErrorDuringPreApplyWithHelp(int $in_active, int $in_stage, a
             ->toString();
           // Reformat the provided results so that they all have the link to the
           // online documentation appended to them.
-          $messages[$message_index] = t('@message See <a href=":url">the help page</a> for information on how to resolve the problem.', ['@message' => $message, ':url' => $url]);
+          $messages[$message_index] = $this->t('@message See <a href=":url">the help page</a> for information on how to resolve the problem.', ['@message' => $message, ':url' => $url]);
         }
       }
       $expected_results[$result_index] = ValidationResult::createError($messages, $result->summary);
diff --git a/core/modules/package_manager/tests/src/Kernel/ComposerValidatorTest.php b/core/modules/package_manager/tests/src/Kernel/ComposerValidatorTest.php
index e5d2e2bc68384fb6ab4af9a0adc73b2cb3dc9afb..5615a76c67318a738f498f5e7b139baafdd276f8 100644
--- a/core/modules/package_manager/tests/src/Kernel/ComposerValidatorTest.php
+++ b/core/modules/package_manager/tests/src/Kernel/ComposerValidatorTest.php
@@ -4,6 +4,7 @@
 
 namespace Drupal\Tests\package_manager\Kernel;
 
+use Drupal\Core\StringTranslation\StringTranslationTrait;
 use Drupal\fixture_manipulator\ActiveFixtureManipulator;
 use Drupal\package_manager\Event\PreApplyEvent;
 use Drupal\package_manager\Event\PreCreateEvent;
@@ -16,6 +17,8 @@
  */
 class ComposerValidatorTest extends PackageManagerKernelTestBase {
 
+  use StringTranslationTrait;
+
   /**
    * Data provider for testComposerSettingsValidation().
    *
@@ -156,7 +159,7 @@ public function testLinkToOnlineHelp(array $config, array $expected_messages): v
     $this->enableModules(['help']);
     (new ActiveFixtureManipulator())->addConfig($config)->commitChanges();
 
-    $result = ValidationResult::createError($expected_messages, t("Composer settings don't satisfy Package Manager's requirements."));
+    $result = ValidationResult::createError($expected_messages, $this->t("Composer settings don't satisfy Package Manager's requirements."));
     $this->assertStatusCheckResults([$result]);
   }
 
diff --git a/core/modules/package_manager/tests/src/Kernel/EnvironmentSupportValidatorTest.php b/core/modules/package_manager/tests/src/Kernel/EnvironmentSupportValidatorTest.php
index 2e9a3909bf9c583d688e68a909ecc586856688b8..7ae3424270f843cd98d649f18a47c0cb0be33d1d 100644
--- a/core/modules/package_manager/tests/src/Kernel/EnvironmentSupportValidatorTest.php
+++ b/core/modules/package_manager/tests/src/Kernel/EnvironmentSupportValidatorTest.php
@@ -4,6 +4,7 @@
 
 namespace Drupal\Tests\package_manager\Kernel;
 
+use Drupal\Core\StringTranslation\StringTranslationTrait;
 use Drupal\package_manager\Event\PreApplyEvent;
 use Drupal\package_manager\Event\PreCreateEvent;
 use Drupal\package_manager\Event\StatusCheckEvent;
@@ -17,6 +18,8 @@
  */
 class EnvironmentSupportValidatorTest extends PackageManagerKernelTestBase {
 
+  use StringTranslationTrait;
+
   /**
    * Tests handling of an invalid URL in the environment support variable.
    */
@@ -24,7 +27,7 @@ public function testInvalidUrl(): void {
     putenv(EnvironmentSupportValidator::VARIABLE_NAME . '=broken/url.org');
 
     $result = ValidationResult::createError([
-      t('Package Manager is not supported by your environment.'),
+      $this->t('Package Manager is not supported by your environment.'),
     ]);
     foreach ([PreCreateEvent::class, StatusCheckEvent::class] as $event_class) {
       $this->assertEventPropagationStopped($event_class, [$this->container->get(EnvironmentSupportValidator::class), 'validate']);
@@ -42,7 +45,7 @@ public function testInvalidUrlDuringPreApply(): void {
     });
 
     $result = ValidationResult::createError([
-      t('Package Manager is not supported by your environment.'),
+      $this->t('Package Manager is not supported by your environment.'),
     ]);
 
     $this->assertEventPropagationStopped(PreApplyEvent::class, [$this->container->get(EnvironmentSupportValidator::class), 'validate']);
@@ -57,7 +60,7 @@ public function testValidUrl(): void {
     putenv(EnvironmentSupportValidator::VARIABLE_NAME . '=' . $url);
 
     $result = ValidationResult::createError([
-      t('<a href=":url">Package Manager is not supported by your environment.</a>', [':url' => $url]),
+      $this->t('<a href=":url">Package Manager is not supported by your environment.</a>', [':url' => $url]),
     ]);
     $this->assertStatusCheckResults([$result]);
     $this->assertResults([$result], PreCreateEvent::class);
@@ -73,7 +76,7 @@ public function testValidUrlDuringPreApply(): void {
     });
 
     $result = ValidationResult::createError([
-      t('<a href=":url">Package Manager is not supported by your environment.</a>', [':url' => $url]),
+      $this->t('<a href=":url">Package Manager is not supported by your environment.</a>', [':url' => $url]),
     ]);
     $this->assertResults([$result], PreApplyEvent::class);
   }
diff --git a/core/modules/package_manager/tests/src/Kernel/FailureMarkerTest.php b/core/modules/package_manager/tests/src/Kernel/FailureMarkerTest.php
index a41de4a9220019324b5ea73750a5ccd78232594b..9ca7a0d3803ae48a8ff50e74c3d3007291a20a07 100644
--- a/core/modules/package_manager/tests/src/Kernel/FailureMarkerTest.php
+++ b/core/modules/package_manager/tests/src/Kernel/FailureMarkerTest.php
@@ -4,6 +4,7 @@
 
 namespace Drupal\Tests\package_manager\Kernel;
 
+use Drupal\Core\StringTranslation\StringTranslationTrait;
 use Drupal\package_manager\Event\CollectPathsToExcludeEvent;
 use Drupal\package_manager\Exception\StageFailureMarkerException;
 use Drupal\package_manager\FailureMarker;
@@ -17,6 +18,8 @@
  */
 class FailureMarkerTest extends PackageManagerKernelTestBase {
 
+  use StringTranslationTrait;
+
   /**
    * @covers ::getMessage
    * @testWith [true]
@@ -24,7 +27,7 @@ class FailureMarkerTest extends PackageManagerKernelTestBase {
    */
   public function testGetMessageWithoutThrowable(bool $include_backtrace): void {
     $failure_marker = $this->container->get(FailureMarker::class);
-    $failure_marker->write($this->createStage(), t('Disastrous catastrophe!'));
+    $failure_marker->write($this->createStage(), $this->t('Disastrous catastrophe!'));
 
     $this->assertMatchesRegularExpression('/^Disastrous catastrophe!$/', $failure_marker->getMessage($include_backtrace));
   }
@@ -36,7 +39,7 @@ public function testGetMessageWithoutThrowable(bool $include_backtrace): void {
    */
   public function testGetMessageWithThrowable(bool $include_backtrace): void {
     $failure_marker = $this->container->get(FailureMarker::class);
-    $failure_marker->write($this->createStage(), t('Disastrous catastrophe!'), new \Exception('Witchcraft!'));
+    $failure_marker->write($this->createStage(), $this->t('Disastrous catastrophe!'), new \Exception('Witchcraft!'));
 
     $expected_pattern = $include_backtrace
       ? <<<REGEXP
@@ -76,7 +79,7 @@ public function testExceptionForInvalidYaml(): void {
    */
   public function testAssertNotExists(): void {
     $failure_marker = $this->container->get(FailureMarker::class);
-    $failure_marker->write($this->createStage(), t('Something wicked occurred here.'), new \Exception('Witchcraft!'));
+    $failure_marker->write($this->createStage(), $this->t('Something wicked occurred here.'), new \Exception('Witchcraft!'));
 
     $this->expectException(StageFailureMarkerException::class);
     $this->expectExceptionMessageMatches('/^Something wicked occurred here. Caused by Exception, with this message: Witchcraft!\nBacktrace:\n#0 .*/');
diff --git a/core/modules/package_manager/tests/src/Kernel/LockFileValidatorTest.php b/core/modules/package_manager/tests/src/Kernel/LockFileValidatorTest.php
index bcd32f639dfbd3587080a0a4158b34781aa34421..a30c36a5d906c8782faecbaa074abe96169a7bc2 100644
--- a/core/modules/package_manager/tests/src/Kernel/LockFileValidatorTest.php
+++ b/core/modules/package_manager/tests/src/Kernel/LockFileValidatorTest.php
@@ -5,6 +5,7 @@
 namespace Drupal\Tests\package_manager\Kernel;
 
 use Drupal\Core\DependencyInjection\ContainerBuilder;
+use Drupal\Core\StringTranslation\StringTranslationTrait;
 use Drupal\package_manager\ComposerInspector;
 use Drupal\package_manager\Event\PreApplyEvent;
 use Drupal\package_manager\Event\PreCreateEvent;
@@ -24,6 +25,8 @@
  */
 class LockFileValidatorTest extends PackageManagerKernelTestBase {
 
+  use StringTranslationTrait;
+
   /**
    * The path of the active directory in the test project.
    *
@@ -72,7 +75,7 @@ public function testCreateWithNoLock(): void {
     $project_root = $this->container->get(PathLocator::class)->getProjectRoot();
     $lock_file_path = $project_root . DIRECTORY_SEPARATOR . 'composer.lock';
     $no_lock = ValidationResult::createError([
-      t('The active lock file (@file) does not exist.', ['@file' => $lock_file_path]),
+      $this->t('The active lock file (@file) does not exist.', ['@file' => $lock_file_path]),
     ]);
     $stage = $this->assertResults([$no_lock], PreCreateEvent::class);
     // The stage was not created successfully, so the status check should be
@@ -111,9 +114,9 @@ public function testLockFileChanged(string $event_class): void {
       file_put_contents($this->activeDir . '/composer.lock', json_encode($lock, JSON_THROW_ON_ERROR));
     }, $event_class);
     $result = ValidationResult::createError([
-      t('Unexpected changes were detected in the active lock file (@file), which indicates that other Composer operations were performed since this Package Manager operation started. This can put the code base into an unreliable state and therefore is not allowed.',
+      $this->t('Unexpected changes were detected in the active lock file (@file), which indicates that other Composer operations were performed since this Package Manager operation started. This can put the code base into an unreliable state and therefore is not allowed.',
        ['@file' => $this->activeDir . '/composer.lock']),
-    ], t('Problem detected in lock file during stage operations.'));
+    ], $this->t('Problem detected in lock file during stage operations.'));
     $stage = $this->assertResults([$result], $event_class);
     // A status check should agree that there is an error here.
     $this->assertStatusCheckResults([$result], $stage);
@@ -133,10 +136,10 @@ public function testLockFileDeleted(string $event_class): void {
       unlink($this->activeDir . '/composer.lock');
     }, $event_class);
     $result = ValidationResult::createError([
-      t('The active lock file (@file) does not exist.', [
+      $this->t('The active lock file (@file) does not exist.', [
         '@file' => $this->activeDir . '/composer.lock',
       ]),
-    ], t('Problem detected in lock file during stage operations.'));
+    ], $this->t('Problem detected in lock file during stage operations.'));
     $stage = $this->assertResults([$result], $event_class);
     // A status check should agree that there is an error here.
     $this->assertStatusCheckResults([$result], $stage);
@@ -181,8 +184,8 @@ public function testApplyWithNoChange(): void {
     NoOpStager::setLockFileShouldChange(FALSE);
 
     $result = ValidationResult::createError([
-      t('There appear to be no pending Composer operations because the active lock file (<PROJECT_ROOT>/composer.lock) and the staged lock file (<STAGE_DIR>/composer.lock) are identical.'),
-    ], t('Problem detected in lock file during stage operations.'));
+      $this->t('There appear to be no pending Composer operations because the active lock file (<PROJECT_ROOT>/composer.lock) and the staged lock file (<STAGE_DIR>/composer.lock) are identical.'),
+    ], $this->t('Problem detected in lock file during stage operations.'));
     $stage = $this->assertResults([$result], PreApplyEvent::class);
     // A status check shouldn't produce raise any errors, because it's only
     // during pre-apply that we care if there are any pending Composer
diff --git a/core/modules/package_manager/tests/src/Kernel/OverwriteExistingPackagesValidatorTest.php b/core/modules/package_manager/tests/src/Kernel/OverwriteExistingPackagesValidatorTest.php
index 93360a5c50065f334fd885b12973629d80b551c5..46b2adc2138566810bf665af90d664716d0468ad 100644
--- a/core/modules/package_manager/tests/src/Kernel/OverwriteExistingPackagesValidatorTest.php
+++ b/core/modules/package_manager/tests/src/Kernel/OverwriteExistingPackagesValidatorTest.php
@@ -4,6 +4,7 @@
 
 namespace Drupal\Tests\package_manager\Kernel;
 
+use Drupal\Core\StringTranslation\StringTranslationTrait;
 use Drupal\fixture_manipulator\ActiveFixtureManipulator;
 use Drupal\package_manager\ComposerInspector;
 use Drupal\package_manager\Event\PostCreateEvent;
@@ -21,6 +22,7 @@
 class OverwriteExistingPackagesValidatorTest extends PackageManagerKernelTestBase {
 
   use ComposerInstallersTrait;
+  use StringTranslationTrait;
 
   /**
    * {@inheritdoc}
@@ -144,13 +146,13 @@ public function testNewPackagesOverwriteExisting(): void {
 
     $expected_results = [
       ValidationResult::createError([
-        t('The new package drupal/module_4 will be installed in the directory /modules/module_6, which already exists but is not managed by Composer.'),
+        $this->t('The new package drupal/module_4 will be installed in the directory /modules/module_6, which already exists but is not managed by Composer.'),
       ]),
       ValidationResult::createError([
-        t('The new package drupal/other_module_1 will be installed in the directory /modules/module_1, which already exists but is not managed by Composer.'),
+        $this->t('The new package drupal/other_module_1 will be installed in the directory /modules/module_1, which already exists but is not managed by Composer.'),
       ]),
       ValidationResult::createError([
-        t('The new package drupal/other_module_2 will be installed in the directory /modules/module_2, which already exists but is not managed by Composer.'),
+        $this->t('The new package drupal/other_module_2 will be installed in the directory /modules/module_2, which already exists but is not managed by Composer.'),
       ]),
     ];
     $this->assertResults($expected_results, PreApplyEvent::class);
diff --git a/core/modules/package_manager/tests/src/Kernel/PendingUpdatesValidatorTest.php b/core/modules/package_manager/tests/src/Kernel/PendingUpdatesValidatorTest.php
index d8682d60fae04ae35e33815a0ab88895c6786fde..dd05283269bccf12292539bea917f0508a238559 100644
--- a/core/modules/package_manager/tests/src/Kernel/PendingUpdatesValidatorTest.php
+++ b/core/modules/package_manager/tests/src/Kernel/PendingUpdatesValidatorTest.php
@@ -4,6 +4,7 @@
 
 namespace Drupal\Tests\package_manager\Kernel;
 
+use Drupal\Core\StringTranslation\StringTranslationTrait;
 use Drupal\package_manager\Event\PreCreateEvent;
 use Drupal\package_manager\Exception\StageEventException;
 use Drupal\package_manager\ValidationResult;
@@ -15,6 +16,8 @@
  */
 class PendingUpdatesValidatorTest extends PackageManagerKernelTestBase {
 
+  use StringTranslationTrait;
+
   /**
    * {@inheritdoc}
    */
@@ -44,7 +47,7 @@ public function testPendingUpdateHook(): void {
     require_once __DIR__ . '/../../fixtures/db_update.php';
 
     $result = ValidationResult::createError([
-      t('Some modules have database updates pending. You should run the <a href="/update.php">database update script</a> immediately.'),
+      $this->t('Some modules have database updates pending. You should run the <a href="/update.php">database update script</a> immediately.'),
     ]);
     $this->assertStatusCheckResults([$result]);
     $this->assertResults([$result], PreCreateEvent::class);
@@ -58,7 +61,7 @@ public function testPendingPostUpdate(): void {
     // will think it's pending.
     require_once __DIR__ . '/../../fixtures/post_update.php';
     $result = ValidationResult::createError([
-      t('Some modules have database updates pending. You should run the <a href="/update.php">database update script</a> immediately.'),
+      $this->t('Some modules have database updates pending. You should run the <a href="/update.php">database update script</a> immediately.'),
     ]);
     $this->assertStatusCheckResults([$result]);
     $this->assertResults([$result], PreCreateEvent::class);
@@ -75,7 +78,7 @@ public function testPendingUpdateAfterStaged(): void {
     // will think it's pending.
     require_once __DIR__ . '/../../fixtures/post_update.php';
     $result = ValidationResult::createError([
-      t('Some modules have database updates pending. You should run the <a href="/update.php">database update script</a> immediately.'),
+      $this->t('Some modules have database updates pending. You should run the <a href="/update.php">database update script</a> immediately.'),
     ]);
     try {
       $stage->apply();
diff --git a/core/modules/package_manager/tests/src/Kernel/PhpTufValidatorTest.php b/core/modules/package_manager/tests/src/Kernel/PhpTufValidatorTest.php
index d73d2961d98d199fd5346cf686a6fb476d85b941..3e244a0b3f3f970b7db0b56039c20508bc7b163a 100644
--- a/core/modules/package_manager/tests/src/Kernel/PhpTufValidatorTest.php
+++ b/core/modules/package_manager/tests/src/Kernel/PhpTufValidatorTest.php
@@ -4,6 +4,7 @@
 
 namespace Drupal\Tests\package_manager\Kernel;
 
+use Drupal\Core\StringTranslation\StringTranslationTrait;
 use Drupal\fixture_manipulator\ActiveFixtureManipulator;
 use Drupal\fixture_manipulator\FixtureManipulator;
 use Drupal\package_manager\Event\PreApplyEvent;
@@ -22,6 +23,8 @@
  */
 class PhpTufValidatorTest extends PackageManagerKernelTestBase {
 
+  use StringTranslationTrait;
+
   /**
    * {@inheritdoc}
    */
@@ -72,12 +75,12 @@ public function testPluginNotInstalledInProjectRoot(): void {
       ->updateLock();
 
     $messages = [
-      t('The <code>php-tuf/composer-integration</code> plugin is not installed.'),
+      $this->t('The <code>php-tuf/composer-integration</code> plugin is not installed.'),
       // Composer automatically removes the plugin from the `allow-plugins`
       // list when the plugin package is removed.
-      t('The <code>php-tuf/composer-integration</code> plugin is not listed as an allowed plugin.'),
+      $this->t('The <code>php-tuf/composer-integration</code> plugin is not listed as an allowed plugin.'),
     ];
-    $result = ValidationResult::createError($messages, t('The active directory is not protected by PHP-TUF, which is required to use Package Manager securely.'));
+    $result = ValidationResult::createError($messages, $this->t('The active directory is not protected by PHP-TUF, which is required to use Package Manager securely.'));
     $this->assertStatusCheckResults([$result]);
     $this->assertResults([$result], PreCreateEvent::class);
   }
@@ -90,12 +93,12 @@ public function testPluginRemovedFromStagePreRequire(): void {
       ->removePackage(PhpTufValidator::PLUGIN_NAME);
 
     $messages = [
-      t('The <code>php-tuf/composer-integration</code> plugin is not installed.'),
+      $this->t('The <code>php-tuf/composer-integration</code> plugin is not installed.'),
       // Composer automatically removes the plugin from the `allow-plugins`
       // list when the plugin package is removed.
-      t('The <code>php-tuf/composer-integration</code> plugin is not listed as an allowed plugin.'),
+      $this->t('The <code>php-tuf/composer-integration</code> plugin is not listed as an allowed plugin.'),
     ];
-    $result = ValidationResult::createError($messages, t('The stage directory is not protected by PHP-TUF, which is required to use Package Manager securely.'));
+    $result = ValidationResult::createError($messages, $this->t('The stage directory is not protected by PHP-TUF, which is required to use Package Manager securely.'));
     $this->assertResults([$result], PreRequireEvent::class);
   }
 
@@ -112,12 +115,12 @@ public function testPluginRemovedFromStagePreApply(): void {
       ->commitChanges($stage->getStageDirectory());
 
     $messages = [
-      t('The <code>php-tuf/composer-integration</code> plugin is not installed.'),
+      $this->t('The <code>php-tuf/composer-integration</code> plugin is not installed.'),
       // Composer automatically removes the plugin from the `allow-plugins`
       // list when the plugin package is removed.
-      t('The <code>php-tuf/composer-integration</code> plugin is not listed as an allowed plugin.'),
+      $this->t('The <code>php-tuf/composer-integration</code> plugin is not listed as an allowed plugin.'),
     ];
-    $result = ValidationResult::createError($messages, t('The stage directory is not protected by PHP-TUF, which is required to use Package Manager securely.'));
+    $result = ValidationResult::createError($messages, $this->t('The stage directory is not protected by PHP-TUF, which is required to use Package Manager securely.'));
     try {
       $stage->apply();
       $this->fail('Expected an exception but none was thrown.');
@@ -195,7 +198,7 @@ public static function providerInvalidConfigurationInStage(): \Generator {
   public function testInvalidConfigurationInProjectRoot(array $config, array $expected_messages): void {
     (new ActiveFixtureManipulator())->addConfig($config)->commitChanges()->updateLock();
 
-    $result = ValidationResult::createError($expected_messages, t('The active directory is not protected by PHP-TUF, which is required to use Package Manager securely.'));
+    $result = ValidationResult::createError($expected_messages, $this->t('The active directory is not protected by PHP-TUF, which is required to use Package Manager securely.'));
     $this->assertStatusCheckResults([$result]);
     $this->assertResults([$result], PreCreateEvent::class);
   }
@@ -230,7 +233,7 @@ public function testInvalidConfigurationInStage(array $config, array $expected_m
         ->removeSubscriber($lock_file_validator);
     }
 
-    $result = ValidationResult::createError($expected_messages, t('The stage directory is not protected by PHP-TUF, which is required to use Package Manager securely.'));
+    $result = ValidationResult::createError($expected_messages, $this->t('The stage directory is not protected by PHP-TUF, which is required to use Package Manager securely.'));
     $this->assertResults([$result], $event_class);
   }
 
diff --git a/core/modules/package_manager/tests/src/Kernel/RsyncValidatorTest.php b/core/modules/package_manager/tests/src/Kernel/RsyncValidatorTest.php
index e066100e1882e15a45165b915c895338914606bf..188c654929dd496aa4d71f4ac4307eaffb3cea4e 100644
--- a/core/modules/package_manager/tests/src/Kernel/RsyncValidatorTest.php
+++ b/core/modules/package_manager/tests/src/Kernel/RsyncValidatorTest.php
@@ -5,6 +5,7 @@
 namespace Drupal\Tests\package_manager\Kernel;
 
 use Drupal\Core\DependencyInjection\ContainerBuilder;
+use Drupal\Core\StringTranslation\StringTranslationTrait;
 use Drupal\package_manager\Event\PreCreateEvent;
 use Drupal\package_manager\ValidationResult;
 use Drupal\package_manager\Validator\RsyncValidator;
@@ -20,6 +21,8 @@
  */
 class RsyncValidatorTest extends PackageManagerKernelTestBase {
 
+  use StringTranslationTrait;
+
   /**
    * The mocked executable finder.
    *
@@ -61,14 +64,14 @@ public function testPreCreateFailsIfRsyncNotFound(): void {
     $this->executableFinder->find('rsync')->willThrow(new LogicException($message));
 
     $result = ValidationResult::createError([
-      t('<code>rsync</code> is not available.'),
+      $this->t('<code>rsync</code> is not available.'),
     ]);
     $this->assertResults([$result], PreCreateEvent::class);
 
     $this->enableModules(['help']);
 
     $result = ValidationResult::createError([
-      t('<code>rsync</code> is not available. See the <a href="/admin/help/package_manager#package-manager-faq-rsync">Package Manager help</a> for more information on how to resolve this.'),
+      $this->t('<code>rsync</code> is not available. See the <a href="/admin/help/package_manager#package-manager-faq-rsync">Package Manager help</a> for more information on how to resolve this.'),
     ]);
     $this->assertResults([$result], PreCreateEvent::class);
   }
diff --git a/core/modules/package_manager/tests/src/Kernel/StageBaseTest.php b/core/modules/package_manager/tests/src/Kernel/StageBaseTest.php
index 0ccc219f7d3a94f39ab4a87a0771ee0cf71f6629..1b8fa9bdae1ff39395baed8328aaecae3cdb9c4a 100644
--- a/core/modules/package_manager/tests/src/Kernel/StageBaseTest.php
+++ b/core/modules/package_manager/tests/src/Kernel/StageBaseTest.php
@@ -5,6 +5,7 @@
 namespace Drupal\Tests\package_manager\Kernel;
 
 use Drupal\Core\DependencyInjection\ContainerBuilder;
+use Drupal\Core\StringTranslation\StringTranslationTrait;
 use Drupal\Core\StringTranslation\TranslatableMarkup;
 use Drupal\package_manager\Event\CollectPathsToExcludeEvent;
 use Drupal\package_manager\Event\PreCreateEvent;
@@ -30,6 +31,8 @@
  */
 class StageBaseTest extends PackageManagerKernelTestBase {
 
+  use StringTranslationTrait;
+
   /**
    * {@inheritdoc}
    */
@@ -311,7 +314,7 @@ public function testTempStoreMessageExpired(): void {
     $stage = $this->createStage();
     $stage_id = $stage->create();
     $stage->require(['drupal/core:9.8.1']);
-    $stage->destroy(TRUE, t('Force destroy stage.'));
+    $stage->destroy(TRUE, $this->t('Force destroy stage.'));
 
     // Delete the tempstore message stored for the previously destroyed stage.
     $tempstore = $this->container->get('tempstore.shared');
diff --git a/core/modules/package_manager/tests/src/Kernel/StageEventsTest.php b/core/modules/package_manager/tests/src/Kernel/StageEventsTest.php
index 8782d27a44c3a42257c78f2318cb8c3dfed672d1..adffe440b1048757c43e78ecdf0d254fc5f79d9b 100644
--- a/core/modules/package_manager/tests/src/Kernel/StageEventsTest.php
+++ b/core/modules/package_manager/tests/src/Kernel/StageEventsTest.php
@@ -5,6 +5,7 @@
 namespace Drupal\Tests\package_manager\Kernel;
 
 use Drupal\Core\DependencyInjection\ContainerBuilder;
+use Drupal\Core\StringTranslation\StringTranslationTrait;
 use Drupal\package_manager\Event\PostApplyEvent;
 use Drupal\package_manager\Event\PostCreateEvent;
 use Drupal\package_manager\Event\PostRequireEvent;
@@ -28,6 +29,8 @@
  */
 class StageEventsTest extends PackageManagerKernelTestBase implements EventSubscriberInterface {
 
+  use StringTranslationTrait;
+
   /**
    * The events that were fired, in the order they were fired.
    *
@@ -134,7 +137,7 @@ public static function providerValidationResults(): array {
    * @dataProvider providerValidationResults
    */
   public function testValidationResults(string $event_class): void {
-    $error_messages = [t('Burn, baby, burn')];
+    $error_messages = [$this->t('Burn, baby, burn')];
     // Set up an event listener which will only flag an error for the event
     // class under test.
     $handler = function (StageEvent $event) use ($event_class, $error_messages): void {
@@ -157,10 +160,10 @@ public function testAddResult(): void {
     $stage = $this->createStage();
 
     $error = ValidationResult::createError([
-      t('Burn, baby, burn!'),
+      $this->t('Burn, baby, burn!'),
     ]);
     $warning = ValidationResult::createWarning([
-      t('The path ahead is scary...'),
+      $this->t('The path ahead is scary...'),
     ]);
     $excluded_paths = $this->createMock(PathListInterface::class);
 
diff --git a/core/modules/package_manager/tests/src/Kernel/SymlinkValidatorTest.php b/core/modules/package_manager/tests/src/Kernel/SymlinkValidatorTest.php
index 46d36bfb83c4212c6bc3c12131606007821851e6..ef6ed7eaf004eee66f31e6cc9f83dd78bac27ffe 100644
--- a/core/modules/package_manager/tests/src/Kernel/SymlinkValidatorTest.php
+++ b/core/modules/package_manager/tests/src/Kernel/SymlinkValidatorTest.php
@@ -4,6 +4,7 @@
 
 namespace Drupal\Tests\package_manager\Kernel;
 
+use Drupal\Core\StringTranslation\StringTranslationTrait;
 use Drupal\package_manager\Event\PreCreateEvent;
 use Drupal\package_manager\Exception\StageEventException;
 use Drupal\package_manager\PathLocator;
@@ -18,6 +19,8 @@
  */
 class SymlinkValidatorTest extends PackageManagerKernelTestBase {
 
+  use StringTranslationTrait;
+
   /**
    * Tests that relative symlinks within the same package are supported.
    */
@@ -48,7 +51,7 @@ public function testHardLinks(): void {
 
     link($project_root . '/composer.json', $project_root . '/composer.link');
     $result = ValidationResult::createError([
-      t('The %which directory at %dir contains hard links, which is not supported. The first one is %file.', [
+      $this->t('The %which directory at %dir contains hard links, which is not supported. The first one is %file.', [
         '%which' => 'active',
         '%dir' => $project_root,
         '%file' => $project_root . '/composer.json',
@@ -66,7 +69,7 @@ public function testAbsoluteSymlinks(): void {
 
     symlink($project_root . '/composer.json', $project_root . '/composer.link');
     $result = ValidationResult::createError([
-      t('The %which directory at %dir contains absolute links, which is not supported. The first one is %file.', [
+      $this->t('The %which directory at %dir contains absolute links, which is not supported. The first one is %file.', [
         '%which' => 'active',
         '%dir' => $project_root,
         '%file' => $project_root . '/composer.link',
@@ -89,7 +92,7 @@ public function testSymlinkPointingOutsideProjectRoot(): void {
     chdir($project_root);
     symlink('../hello.txt', 'fail.txt');
     $result = ValidationResult::createError([
-      t('The %which directory at %dir contains links that point outside the codebase, which is not supported. The first one is %file.', [
+      $this->t('The %which directory at %dir contains links that point outside the codebase, which is not supported. The first one is %file.', [
         '%which' => 'active',
         '%dir' => $project_root,
         '%file' => $project_root . '/fail.txt',
@@ -118,7 +121,7 @@ public function testSymlinkPointingOutsideStageDirectory(): void {
     symlink('../hello.txt', 'fail.txt');
 
     $result = ValidationResult::createError([
-      t('The %which directory at %dir contains links that point outside the codebase, which is not supported. The first one is %file.', [
+      $this->t('The %which directory at %dir contains links that point outside the codebase, which is not supported. The first one is %file.', [
         '%which' => 'staging',
         '%dir' => $stage_dir,
         '%file' => $stage_dir . '/fail.txt',
@@ -169,7 +172,7 @@ public function testSymlinksNotAllowedOnWindows(): void {
     symlink('composer.json', 'composer.link');
 
     $result = ValidationResult::createError([
-      t('The %which directory at %dir contains links, which is not supported on Windows. The first one is %file.', [
+      $this->t('The %which directory at %dir contains links, which is not supported on Windows. The first one is %file.', [
         '%which' => 'active',
         '%dir' => $project_root,
         '%file' => $project_root . '/composer.link',
diff --git a/core/phpcs.xml.dist b/core/phpcs.xml.dist
index 47d0a73e4a306304b9b7b8c42309b20342ec9cf7..60105a430d96fa8e383750e6537b664057d74287 100644
--- a/core/phpcs.xml.dist
+++ b/core/phpcs.xml.dist
@@ -191,6 +191,7 @@
     <include-pattern>*/ListBuilder/*</include-pattern>
     <include-pattern>*/tests/*/Form/*</include-pattern>
     <include-pattern>*/modules/system/tests/modules/*</include-pattern>
+    <include-pattern>*/Kernel*/*</include-pattern>
   </rule>
 
   <!-- Generic sniffs -->
diff --git a/core/tests/Drupal/KernelTests/ConfigFormTestBase.php b/core/tests/Drupal/KernelTests/ConfigFormTestBase.php
index aa3bda340b15341946ea95574142a41c443d8fda..2d605cd817482ab3dee30c488172ee5d00d4df7c 100644
--- a/core/tests/Drupal/KernelTests/ConfigFormTestBase.php
+++ b/core/tests/Drupal/KernelTests/ConfigFormTestBase.php
@@ -5,6 +5,7 @@
 namespace Drupal\KernelTests;
 
 use Drupal\Core\Form\FormState;
+use Drupal\Core\StringTranslation\StringTranslationTrait;
 
 /**
  * Full generic test suite for any form that data with the configuration system.
@@ -13,6 +14,9 @@
  *   For a full working implementation.
  */
 abstract class ConfigFormTestBase extends KernelTestBase {
+
+  use StringTranslationTrait;
+
   /**
    * Form ID to use for testing.
    *
@@ -54,7 +58,7 @@ public function testConfigForm(): void {
     $errors = $form_state->getErrors();
     $valid_form = empty($errors);
     $values = print_r($values, TRUE);
-    $errors = $valid_form ? t('None') : implode(' ', $errors);
+    $errors = $valid_form ? $this->t('None') : implode(' ', $errors);
     $this->assertTrue($valid_form, sprintf('Input values: %s<br/>Validation handler errors: %s', $values, $errors));
     foreach ($this->values as $data) {
       $this->assertEquals($this->config($data['#config_name'])->get($data['#config_key']), $data['#value']);
diff --git a/core/tests/Drupal/KernelTests/Core/Common/XssUnitTest.php b/core/tests/Drupal/KernelTests/Core/Common/XssUnitTest.php
index ce61fc72e76e67083d2343b7567c2bf612c6de59..91a6221be7e744f3416b47712493bc51c37d7b86 100644
--- a/core/tests/Drupal/KernelTests/Core/Common/XssUnitTest.php
+++ b/core/tests/Drupal/KernelTests/Core/Common/XssUnitTest.php
@@ -5,6 +5,7 @@
 namespace Drupal\KernelTests\Core\Common;
 
 use Drupal\Component\Utility\UrlHelper;
+use Drupal\Core\StringTranslation\StringTranslationTrait;
 use Drupal\KernelTests\KernelTestBase;
 
 /**
@@ -18,6 +19,8 @@
  */
 class XssUnitTest extends KernelTestBase {
 
+  use StringTranslationTrait;
+
   /**
    * {@inheritdoc}
    */
@@ -35,11 +38,11 @@ protected function setUp(): void {
    * Tests t() functionality.
    */
   public function testT(): void {
-    $text = t('Simple text');
+    $text = $this->t('Simple text');
     $this->assertSame('Simple text', (string) $text, 't leaves simple text alone.');
-    $text = t('Escaped text: @value', ['@value' => '<script>']);
+    $text = $this->t('Escaped text: @value', ['@value' => '<script>']);
     $this->assertSame('Escaped text: &lt;script&gt;', (string) $text, 't replaces and escapes string.');
-    $text = t('Placeholder text: %value', ['%value' => '<script>']);
+    $text = $this->t('Placeholder text: %value', ['%value' => '<script>']);
     $this->assertSame('Placeholder text: <em class="placeholder">&lt;script&gt;</em>', (string) $text, 't replaces, escapes and themes string.');
   }
 
diff --git a/core/tests/Drupal/KernelTests/Core/Entity/EntityDefinitionUpdateTest.php b/core/tests/Drupal/KernelTests/Core/Entity/EntityDefinitionUpdateTest.php
index 97cfacb815e3b95c22f3b35f25f9de9b9216ab37..a428509dfe581be6fe0e988efc6ab9bde23c9376 100644
--- a/core/tests/Drupal/KernelTests/Core/Entity/EntityDefinitionUpdateTest.php
+++ b/core/tests/Drupal/KernelTests/Core/Entity/EntityDefinitionUpdateTest.php
@@ -15,6 +15,7 @@
 use Drupal\Core\Field\FieldException;
 use Drupal\Core\Field\FieldStorageDefinitionEvents;
 use Drupal\Core\Language\LanguageInterface;
+use Drupal\Core\StringTranslation\StringTranslationTrait;
 use Drupal\Core\StringTranslation\TranslatableMarkup;
 use Drupal\entity_test\FieldStorageDefinition;
 use Drupal\entity_test_update\Entity\EntityTestUpdate;
@@ -31,6 +32,7 @@
 class EntityDefinitionUpdateTest extends EntityKernelTestBase {
 
   use EntityDefinitionTestTrait;
+  use StringTranslationTrait;
 
   /**
    * The entity definition update manager.
@@ -118,11 +120,11 @@ public function testEntityTypeUpdateWithoutData(): void {
     $this->assertTrue($this->entityDefinitionUpdateManager->needsUpdates(), 'EntityDefinitionUpdateManager reports that updates are needed.');
     $expected = [
       'entity_test_update' => [
-        t('The %entity_type entity type needs to be updated.', ['%entity_type' => $this->entityTypeManager->getDefinition('entity_test_update')->getLabel()]),
+        $this->t('The %entity_type entity type needs to be updated.', ['%entity_type' => $this->entityTypeManager->getDefinition('entity_test_update')->getLabel()]),
         // The revision key is now defined, so the revision field needs to be
         // created.
-        t('The %field_name field needs to be installed.', ['%field_name' => 'Revision ID']),
-        t('The %field_name field needs to be installed.', ['%field_name' => 'Default revision']),
+        $this->t('The %field_name field needs to be installed.', ['%field_name' => 'Revision ID']),
+        $this->t('The %field_name field needs to be installed.', ['%field_name' => 'Default revision']),
       ],
     ];
     $this->assertEquals($expected, $this->entityDefinitionUpdateManager->getChangeSummary(), 'EntityDefinitionUpdateManager reports the expected change summary.');
@@ -662,7 +664,7 @@ public function testEntityIndexCreateDeleteWithoutData(): void {
     $this->assertTrue($this->entityDefinitionUpdateManager->needsUpdates(), 'EntityDefinitionUpdateManager reports that updates are needed.');
     $expected = [
       'entity_test_update' => [
-        t('The %entity_type entity type needs to be updated.', ['%entity_type' => $this->entityTypeManager->getDefinition('entity_test_update')->getLabel()]),
+        $this->t('The %entity_type entity type needs to be updated.', ['%entity_type' => $this->entityTypeManager->getDefinition('entity_test_update')->getLabel()]),
       ],
     ];
     $this->assertEquals($expected, $this->entityDefinitionUpdateManager->getChangeSummary(), 'EntityDefinitionUpdateManager reports the expected change summary.');
@@ -679,7 +681,7 @@ public function testEntityIndexCreateDeleteWithoutData(): void {
     $this->assertTrue($this->entityDefinitionUpdateManager->needsUpdates(), 'EntityDefinitionUpdateManager reports that updates are needed.');
     $expected = [
       'entity_test_update' => [
-        t('The %entity_type entity type needs to be updated.', ['%entity_type' => $this->entityTypeManager->getDefinition('entity_test_update')->getLabel()]),
+        $this->t('The %entity_type entity type needs to be updated.', ['%entity_type' => $this->entityTypeManager->getDefinition('entity_test_update')->getLabel()]),
       ],
     ];
     $this->assertEquals($expected, $this->entityDefinitionUpdateManager->getChangeSummary(), 'EntityDefinitionUpdateManager reports the expected change summary.');
@@ -821,7 +823,7 @@ public function testSingleActionCalls(): void {
     $message = 'A field cannot be installed on a non-existing entity type';
     try {
       $storage_definition = BaseFieldDefinition::create('string')
-        ->setLabel(t('A new revisionable base field'))
+        ->setLabel($this->t('A new revisionable base field'))
         ->setRevisionable(TRUE);
       $this->entityDefinitionUpdateManager->installFieldStorageDefinition('bar', 'foo', 'entity_test', $storage_definition);
       $this->fail($message);
@@ -838,7 +840,7 @@ public function testSingleActionCalls(): void {
     // Create a new base field.
     $this->addRevisionableBaseField();
     $storage_definition = BaseFieldDefinition::create('string')
-      ->setLabel(t('A new revisionable base field'))
+      ->setLabel($this->t('A new revisionable base field'))
       ->setRevisionable(TRUE);
     $this->assertFalse($db_schema->fieldExists('entity_test_update', 'new_base_field'), "New field 'new_base_field' does not exist before applying the update.");
     $this->entityDefinitionUpdateManager->installFieldStorageDefinition('new_base_field', 'entity_test_update', 'entity_test', $storage_definition);
@@ -853,7 +855,7 @@ public function testSingleActionCalls(): void {
     $storage_definition = BaseFieldDefinition::create('text')
       ->setName('new_base_field')
       ->setTargetEntityTypeId('entity_test_update')
-      ->setLabel(t('A new revisionable base field'))
+      ->setLabel($this->t('A new revisionable base field'))
       ->setRevisionable(TRUE);
     $this->entityDefinitionUpdateManager->updateFieldStorageDefinition($storage_definition);
     $this->assertFalse($db_schema->fieldExists('entity_test_update', 'new_base_field'), "Previous schema for 'new_base_field' no longer exists.");
@@ -1003,7 +1005,7 @@ public function testInitialValue(): void {
     // Add a base field with an initial value.
     $this->addBaseField();
     $storage_definition = BaseFieldDefinition::create('string')
-      ->setLabel(t('A new base field'))
+      ->setLabel($this->t('A new base field'))
       ->setInitialValue('test value');
 
     $this->assertFalse($db_schema->fieldExists('entity_test_update', 'new_base_field'), "New field 'new_base_field' does not exist before applying the update.");
@@ -1026,7 +1028,7 @@ public function testInitialValueFromFieldErrorHandling(): void {
     try {
       $this->addBaseField();
       $storage_definition = BaseFieldDefinition::create('string')
-        ->setLabel(t('A new base field'))
+        ->setLabel($this->t('A new base field'))
         ->setInitialValueFromField('field_that_does_not_exist');
       $this->entityDefinitionUpdateManager->installFieldStorageDefinition('new_base_field', 'entity_test_update', 'entity_test', $storage_definition);
       $this->fail('Using a non-existent field as initial value does not work.');
@@ -1038,7 +1040,7 @@ public function testInitialValueFromFieldErrorHandling(): void {
     try {
       $this->addBaseField();
       $storage_definition = BaseFieldDefinition::create('integer')
-        ->setLabel(t('A new base field'))
+        ->setLabel($this->t('A new base field'))
         ->setInitialValueFromField('name');
       $this->entityDefinitionUpdateManager->installFieldStorageDefinition('new_base_field', 'entity_test_update', 'entity_test', $storage_definition);
       $this->fail('Using a field of a different type as initial value does not work.');
@@ -1051,7 +1053,7 @@ public function testInitialValueFromFieldErrorHandling(): void {
       // Add a base field that will not be stored in the shared tables.
       $initial_field = BaseFieldDefinition::create('string')
         ->setName('initial_field')
-        ->setLabel(t('An initial field'))
+        ->setLabel($this->t('An initial field'))
         ->setCardinality(2);
       $this->state->set('entity_test_update.additional_base_field_definitions', ['initial_field' => $initial_field]);
       $this->entityDefinitionUpdateManager->installFieldStorageDefinition('initial_field', 'entity_test_update', 'entity_test', $initial_field);
@@ -1060,7 +1062,7 @@ public function testInitialValueFromFieldErrorHandling(): void {
       // as the source of its initial values.
       $new_base_field = BaseFieldDefinition::create('string')
         ->setName('new_base_field')
-        ->setLabel(t('A new base field'))
+        ->setLabel($this->t('A new base field'))
         ->setInitialValueFromField('initial_field');
       $this->state->set('entity_test_update.additional_base_field_definitions', ['initial_field' => $initial_field, 'new_base_field' => $new_base_field]);
       $this->entityDefinitionUpdateManager->installFieldStorageDefinition('new_base_field', 'entity_test_update', 'entity_test', $new_base_field);
diff --git a/core/tests/Drupal/KernelTests/Core/Entity/FieldableEntityDefinitionUpdateTest.php b/core/tests/Drupal/KernelTests/Core/Entity/FieldableEntityDefinitionUpdateTest.php
index 1f0f9762070ddac280a20be38ecd587b2a242454..d0fdbf930f0383c004e625d3571e0158e2cae7c0 100644
--- a/core/tests/Drupal/KernelTests/Core/Entity/FieldableEntityDefinitionUpdateTest.php
+++ b/core/tests/Drupal/KernelTests/Core/Entity/FieldableEntityDefinitionUpdateTest.php
@@ -7,6 +7,7 @@
 use Drupal\Core\Entity\EntityStorageException;
 use Drupal\Core\Field\BaseFieldDefinition;
 use Drupal\Core\Site\Settings;
+use Drupal\Core\StringTranslation\StringTranslationTrait;
 use Drupal\language\Entity\ConfigurableLanguage;
 use Drupal\Tests\system\Functional\Entity\Traits\EntityDefinitionTestTrait;
 
@@ -20,6 +21,7 @@
 class FieldableEntityDefinitionUpdateTest extends EntityKernelTestBase {
 
   use EntityDefinitionTestTrait;
+  use StringTranslationTrait;
 
   /**
    * The entity definition update manager.
@@ -107,8 +109,8 @@ protected function setUp(): void {
     // updated, so add it to the entity type that is being tested in order to
     // provide test coverage for this special case.
     $fields['changed'] = BaseFieldDefinition::create('changed')
-      ->setLabel(t('Changed'))
-      ->setDescription(t('The time that the content block was last edited.'))
+      ->setLabel($this->t('Changed'))
+      ->setDescription($this->t('The time that the content block was last edited.'))
       ->setTranslatable(TRUE)
       ->setRevisionable(TRUE);
     $this->state->set('entity_test_update.additional_base_field_definitions', $fields);
diff --git a/core/tests/Drupal/KernelTests/Core/TypedData/TypedDataTest.php b/core/tests/Drupal/KernelTests/Core/TypedData/TypedDataTest.php
index 525bef995c99c3914a2bf6f79892f90c2dd28777..c5443287f995a1a00d3dac67a7c7f9d35e9f0bfd 100644
--- a/core/tests/Drupal/KernelTests/Core/TypedData/TypedDataTest.php
+++ b/core/tests/Drupal/KernelTests/Core/TypedData/TypedDataTest.php
@@ -6,6 +6,7 @@
 
 use Drupal\Core\Datetime\DrupalDateTime;
 use Drupal\Core\Field\BaseFieldDefinition;
+use Drupal\Core\StringTranslation\StringTranslationTrait;
 use Drupal\Core\TypedData\DataDefinition;
 use Drupal\Core\TypedData\ListDataDefinition;
 use Drupal\Core\TypedData\MapDataDefinition;
@@ -31,6 +32,8 @@
  */
 class TypedDataTest extends KernelTestBase {
 
+  use StringTranslationTrait;
+
   /**
    * The typed data manager to use.
    *
@@ -610,7 +613,7 @@ public function testTypedDataValidation(): void {
     $this->assertEquals(1, $violations->count());
 
     // Test translating violation messages.
-    $message = t('This value should be %limit or more.', ['%limit' => 5]);
+    $message = $this->t('This value should be %limit or more.', ['%limit' => 5]);
     $this->assertEquals($message, $violations[0]->getMessage(), 'Translated violation message retrieved.');
     $this->assertEquals('', $violations[0]->getPropertyPath());
     $this->assertSame($integer, $violations[0]->getRoot(), 'Root object returned.');
@@ -622,7 +625,7 @@ public function testTypedDataValidation(): void {
       ]);
     $violations = $this->typedDataManager->create($definition, "short")->validate();
     $this->assertEquals(1, $violations->count());
-    $message = t('This value is too short. It should have %limit characters or more.', ['%limit' => 10]);
+    $message = $this->t('This value is too short. It should have %limit characters or more.', ['%limit' => 10]);
     $this->assertEquals($message, $violations[0]->getMessage(), 'Translated violation message retrieved.');
 
     // Test having multiple violations.