diff --git a/core/modules/aggregator/src/Tests/AggregatorTitleTest.php b/core/modules/aggregator/tests/src/Kernel/AggregatorTitleTest.php
similarity index 94%
rename from core/modules/aggregator/src/Tests/AggregatorTitleTest.php
rename to core/modules/aggregator/tests/src/Kernel/AggregatorTitleTest.php
index d599d9a..5b81de3 100644
--- a/core/modules/aggregator/src/Tests/AggregatorTitleTest.php
+++ b/core/modules/aggregator/tests/src/Kernel/AggregatorTitleTest.php
@@ -2,14 +2,14 @@
 
 /**
  * @file
- * Contains \Drupal\aggregator\Tests\AggregatorTitleTest.
+ * Contains \Drupal\Tests\aggregator\Kernel\AggregatorTitleTest.
  */
 
-namespace Drupal\aggregator\Tests;
+namespace Drupal\Tests\aggregator\Kernel;
 
 use Drupal\aggregator\Entity\Feed;
 use Drupal\aggregator\Entity\Item;
-use Drupal\simpletest\KernelTestBase;
+use Drupal\KernelTests\KernelTestBase;
 
 
 /**
diff --git a/core/modules/block/src/Tests/BlockConfigSchemaTest.php b/core/modules/block/tests/src/Kernel/BlockConfigSchemaTest.php
similarity index 93%
rename from core/modules/block/src/Tests/BlockConfigSchemaTest.php
rename to core/modules/block/tests/src/Kernel/BlockConfigSchemaTest.php
index 9d7bcfe..88b8e81 100644
--- a/core/modules/block/src/Tests/BlockConfigSchemaTest.php
+++ b/core/modules/block/tests/src/Kernel/BlockConfigSchemaTest.php
@@ -2,14 +2,14 @@
 
 /**
  * @file
- * Contains \Drupal\block\Tests\BlockConfigSchemaTest.
+ * Contains \Drupal\Tests\block\Kernel\BlockConfigSchemaTest.
  */
 
-namespace Drupal\block\Tests;
+namespace Drupal\Tests\block\Kernel;
 
 use Drupal\block\Entity\Block;
 use Drupal\config\Tests\SchemaCheckTestTrait;
-use Drupal\simpletest\KernelTestBase;
+use Drupal\KernelTests\KernelTestBase;
 
 /**
  * Tests the block config schema.
diff --git a/core/modules/block/src/Tests/BlockStorageUnitTest.php b/core/modules/block/tests/src/Kernel/BlockStorageUnitTest.php
similarity index 97%
rename from core/modules/block/src/Tests/BlockStorageUnitTest.php
rename to core/modules/block/tests/src/Kernel/BlockStorageUnitTest.php
index db892cb..859e32a 100644
--- a/core/modules/block/src/Tests/BlockStorageUnitTest.php
+++ b/core/modules/block/tests/src/Kernel/BlockStorageUnitTest.php
@@ -2,13 +2,13 @@
 
 /**
  * @file
- * Contains \Drupal\block\Tests\BlockStorageUnitTest.
+ * Contains \Drupal\Tests\block\Kernel\BlockStorageUnitTest.
  */
 
-namespace Drupal\block\Tests;
+namespace Drupal\Tests\block\Kernel;
 
 use Drupal\Core\Config\Entity\ConfigEntityStorage;
-use Drupal\simpletest\KernelTestBase;
+use Drupal\KernelTests\KernelTestBase;
 use Drupal\block_test\Plugin\Block\TestHtmlBlock;
 use Drupal\Component\Plugin\Exception\PluginException;
 use Drupal\block\Entity\Block;
diff --git a/core/modules/block/src/Tests/BlockViewBuilderTest.php b/core/modules/block/tests/src/Kernel/BlockViewBuilderTest.php
similarity index 98%
rename from core/modules/block/src/Tests/BlockViewBuilderTest.php
rename to core/modules/block/tests/src/Kernel/BlockViewBuilderTest.php
index fdfa089..be70015 100644
--- a/core/modules/block/src/Tests/BlockViewBuilderTest.php
+++ b/core/modules/block/tests/src/Kernel/BlockViewBuilderTest.php
@@ -2,15 +2,15 @@
 
 /**
  * @file
- * Contains \Drupal\block\Tests\BlockViewBuilderTest.
+ * Contains \Drupal\Tests\block\Kernel\BlockViewBuilderTest.
  */
 
-namespace Drupal\block\Tests;
+namespace Drupal\Tests\block\Kernel;
 
 use Drupal\Component\Utility\Html;
 use Drupal\Core\Cache\Cache;
 use Drupal\Core\Language\LanguageInterface;
-use Drupal\simpletest\KernelTestBase;
+use Drupal\KernelTests\KernelTestBase;
 use Drupal\block\Entity\Block;
 
 /**
diff --git a/core/modules/book/src/Tests/BookUninstallTest.php b/core/modules/book/tests/src/Kernel/BookUninstallTest.php
similarity index 96%
rename from core/modules/book/src/Tests/BookUninstallTest.php
rename to core/modules/book/tests/src/Kernel/BookUninstallTest.php
index 0a18fb1..5cb7327 100644
--- a/core/modules/book/src/Tests/BookUninstallTest.php
+++ b/core/modules/book/tests/src/Kernel/BookUninstallTest.php
@@ -2,14 +2,14 @@
 
 /**
  * @file
- * Contains \Drupal\book\Tests\BookUninstallTest.
+ * Contains \Drupal\Tests\book\Kernel\BookUninstallTest.
  */
 
-namespace Drupal\book\Tests;
+namespace Drupal\Tests\book\Kernel;
 
 use Drupal\node\Entity\Node;
 use Drupal\node\Entity\NodeType;
-use Drupal\simpletest\KernelTestBase;
+use Drupal\KernelTests\KernelTestBase;
 
 /**
  * Tests that the Book module cannot be uninstalled if books exist.
diff --git a/core/modules/breakpoint/src/Tests/BreakpointDiscoveryTest.php b/core/modules/breakpoint/tests/src/Kernel/BreakpointDiscoveryTest.php
similarity index 97%
rename from core/modules/breakpoint/src/Tests/BreakpointDiscoveryTest.php
rename to core/modules/breakpoint/tests/src/Kernel/BreakpointDiscoveryTest.php
index 0b132a9..0328c14 100644
--- a/core/modules/breakpoint/src/Tests/BreakpointDiscoveryTest.php
+++ b/core/modules/breakpoint/tests/src/Kernel/BreakpointDiscoveryTest.php
@@ -1,12 +1,12 @@
 <?php
 /**
  * @file
- * Contains \Drupal\breakpoint\Tests\BreakpointDiscoveryTest.
+ * Contains \Drupal\Tests\breakpoint\Kernel\BreakpointDiscoveryTest.
  */
 
-namespace Drupal\breakpoint\Tests;
+namespace Drupal\Tests\breakpoint\Kernel;
 
-use Drupal\simpletest\KernelTestBase;
+use Drupal\KernelTests\KernelTestBase;
 
 /**
  * Tests discovery of breakpoints provided by themes and modules.
diff --git a/core/modules/ckeditor/src/Tests/CKEditorPluginManagerTest.php b/core/modules/ckeditor/tests/modules/src/Kernel/CKEditorPluginManagerTest.php
similarity index 98%
rename from core/modules/ckeditor/src/Tests/CKEditorPluginManagerTest.php
rename to core/modules/ckeditor/tests/modules/src/Kernel/CKEditorPluginManagerTest.php
index 002de2b..ab11491 100644
--- a/core/modules/ckeditor/src/Tests/CKEditorPluginManagerTest.php
+++ b/core/modules/ckeditor/tests/modules/src/Kernel/CKEditorPluginManagerTest.php
@@ -2,13 +2,13 @@
 
 /**
  * @file
- * Contains \Drupal\ckeditor\Tests\CKEditorPluginManagerTest.
+ * Contains \Drupal\Tests\ckeditor\Kernel\CKEditorPluginManagerTest.
  */
 
-namespace Drupal\ckeditor\Tests;
+namespace Drupal\Tests\ckeditor\Kernel;
 
 use Drupal\editor\Entity\Editor;
-use Drupal\simpletest\KernelTestBase;
+use Drupal\KernelTests\KernelTestBase;
 use Drupal\filter\Entity\FilterFormat;
 
 /**
diff --git a/core/modules/ckeditor/src/Tests/CKEditorTest.php b/core/modules/ckeditor/tests/modules/src/Kernel/CKEditorTest.php
similarity index 99%
rename from core/modules/ckeditor/src/Tests/CKEditorTest.php
rename to core/modules/ckeditor/tests/modules/src/Kernel/CKEditorTest.php
index 5ac3a04..b421525 100644
--- a/core/modules/ckeditor/src/Tests/CKEditorTest.php
+++ b/core/modules/ckeditor/tests/modules/src/Kernel/CKEditorTest.php
@@ -2,12 +2,12 @@
 
 /**
  * @file
- * Contains \Drupal\ckeditor\Tests\CKEditorTest.
+ * Contains \Drupal\Tests\ckeditor\Kernel\CKEditorTest.
  */
 
-namespace Drupal\ckeditor\Tests;
+namespace Drupal\Tests\ckeditor\Kernel;
 
-use Drupal\simpletest\KernelTestBase;
+use Drupal\KernelTests\KernelTestBase;
 use Drupal\language\Entity\ConfigurableLanguage;
 use Drupal\editor\Entity\Editor;
 use Drupal\filter\Entity\FilterFormat;
diff --git a/core/modules/comment/src/Tests/CommentStringIdEntitiesTest.php b/core/modules/comment/tests/src/Kernel/CommentStringIdEntitiesTest.php
similarity index 91%
rename from core/modules/comment/src/Tests/CommentStringIdEntitiesTest.php
rename to core/modules/comment/tests/src/Kernel/CommentStringIdEntitiesTest.php
index ef7f48d..ae4627f 100644
--- a/core/modules/comment/src/Tests/CommentStringIdEntitiesTest.php
+++ b/core/modules/comment/tests/src/Kernel/CommentStringIdEntitiesTest.php
@@ -2,13 +2,13 @@
 
 /**
  * @file
- * Contains \Drupal\comment\Tests\CommentStringIdEntitiesTest.
+ * Contains \Drupal\Tests\comment\Kernel\CommentStringIdEntitiesTest.
  */
 
-namespace Drupal\comment\Tests;
+namespace Drupal\Tests\comment\Kernel;
 
 use Drupal\comment\Entity\CommentType;
-use Drupal\simpletest\KernelTestBase;
+use Drupal\KernelTests\KernelTestBase;
 use Drupal\field\Entity\FieldStorageConfig;
 
 /**
diff --git a/core/modules/config/src/Tests/CacheabilityMetadataConfigOverrideTest.php b/core/modules/config/tests/src/Kernel/CacheabilityMetadataConfigOverrideTest.php
similarity index 95%
rename from core/modules/config/src/Tests/CacheabilityMetadataConfigOverrideTest.php
rename to core/modules/config/tests/src/Kernel/CacheabilityMetadataConfigOverrideTest.php
index e559d80..a6f5de9 100644
--- a/core/modules/config/src/Tests/CacheabilityMetadataConfigOverrideTest.php
+++ b/core/modules/config/tests/src/Kernel/CacheabilityMetadataConfigOverrideTest.php
@@ -2,14 +2,14 @@
 
 /**
  * @file
- * Contains \Drupal\config\Tests\CacheabilityMetadataConfigOverrideTest.
+ * Contains \Drupal\Tests\config\Kernel\CacheabilityMetadataConfigOverrideTest.
  */
 
-namespace Drupal\config\Tests;
+namespace Drupal\Tests\config\Kernel;
 
 use Drupal\Core\Entity\EntityManagerInterface;
 use Drupal\config_override_test\Cache\PirateDayCacheContext;
-use Drupal\simpletest\KernelTestBase;
+use Drupal\KernelTests\KernelTestBase;
 
 /**
  * Tests if configuration overrides correctly affect cacheability metadata.
diff --git a/core/modules/config/src/Tests/ConfigEntityNormalizeTest.php b/core/modules/config/tests/src/Kernel/ConfigEntityNormalizeTest.php
similarity index 89%
rename from core/modules/config/src/Tests/ConfigEntityNormalizeTest.php
rename to core/modules/config/tests/src/Kernel/ConfigEntityNormalizeTest.php
index 7e0acef..639cf6d 100644
--- a/core/modules/config/src/Tests/ConfigEntityNormalizeTest.php
+++ b/core/modules/config/tests/src/Kernel/ConfigEntityNormalizeTest.php
@@ -2,12 +2,12 @@
 
 /**
  * @file
- * Contains \Drupal\config\Tests\ConfigEntityNormalizeTest.
+ * Contains \Drupal\Tests\config\Kernel\ConfigEntityNormalizeTest.
  */
 
-namespace Drupal\config\Tests;
+namespace Drupal\Tests\config\Kernel;
 
-use Drupal\simpletest\KernelTestBase;
+use Drupal\KernelTests\KernelTestBase;
 
 /**
  * Tests the listing of configuration entities.
diff --git a/core/modules/config/src/Tests/ConfigEntityStaticCacheTest.php b/core/modules/config/tests/src/Kernel/ConfigEntityStaticCacheTest.php
similarity index 96%
rename from core/modules/config/src/Tests/ConfigEntityStaticCacheTest.php
rename to core/modules/config/tests/src/Kernel/ConfigEntityStaticCacheTest.php
index e36331c..35e68f9 100644
--- a/core/modules/config/src/Tests/ConfigEntityStaticCacheTest.php
+++ b/core/modules/config/tests/src/Kernel/ConfigEntityStaticCacheTest.php
@@ -2,13 +2,13 @@
 
 /**
  * @file
- * Contains \Drupal\config\Tests\ConfigEntityStaticCacheTest.
+ * Contains \Drupal\Tests\config\Kernel\ConfigEntityStaticCacheTest.
  */
 
-namespace Drupal\config\Tests;
+namespace Drupal\Tests\config\Kernel;
 
 use Drupal\config_entity_static_cache_test\ConfigOverrider;
-use Drupal\simpletest\KernelTestBase;
+use Drupal\KernelTests\KernelTestBase;
 
 /**
  * Tests the entity static cache when used by config entities.
diff --git a/core/modules/config/src/Tests/ConfigEntityUnitTest.php b/core/modules/config/tests/src/Kernel/ConfigEntityUnitTest.php
similarity index 96%
rename from core/modules/config/src/Tests/ConfigEntityUnitTest.php
rename to core/modules/config/tests/src/Kernel/ConfigEntityUnitTest.php
index dd6a586..3698691 100644
--- a/core/modules/config/src/Tests/ConfigEntityUnitTest.php
+++ b/core/modules/config/tests/src/Kernel/ConfigEntityUnitTest.php
@@ -2,12 +2,12 @@
 
 /**
  * @file
- * Contains \Drupal\config\Tests\ConfigEntityUnitTest.
+ * Contains \Drupal\Tests\config\Kernel\ConfigEntityUnitTest.
  */
 
-namespace Drupal\config\Tests;
+namespace Drupal\Tests\config\Kernel;
 
-use Drupal\simpletest\KernelTestBase;
+use Drupal\KernelTests\KernelTestBase;
 
 /**
  * Unit tests for configuration entity base methods.
diff --git a/core/modules/config/src/Tests/ConfigImportRecreateTest.php b/core/modules/config/tests/src/Kernel/ConfigImportRecreateTest.php
similarity index 96%
rename from core/modules/config/src/Tests/ConfigImportRecreateTest.php
rename to core/modules/config/tests/src/Kernel/ConfigImportRecreateTest.php
index 163389f..86a7ac7 100644
--- a/core/modules/config/src/Tests/ConfigImportRecreateTest.php
+++ b/core/modules/config/tests/src/Kernel/ConfigImportRecreateTest.php
@@ -2,16 +2,15 @@
 
 /**
  * @file
- * Contains \Drupal\config\Tests\ConfigImportRecreateTest.
+ * Contains \Drupal\Tests\config\Kernel\ConfigImportRecreateTest.
  */
 
-namespace Drupal\config\Tests;
+namespace Drupal\Tests\config\Kernel;
 
 use Drupal\Component\Utility\Unicode;
 use Drupal\Core\Config\ConfigImporter;
 use Drupal\Core\Config\StorageComparer;
 use Drupal\node\Entity\NodeType;
-use Drupal\simpletest\KernelTestBase;
 
 /**
  * Tests importing recreated configuration entities.
diff --git a/core/modules/config/src/Tests/ConfigImportRenameValidationTest.php b/core/modules/config/tests/src/Kernel/ConfigImportRenameValidationTest.php
similarity index 97%
rename from core/modules/config/src/Tests/ConfigImportRenameValidationTest.php
rename to core/modules/config/tests/src/Kernel/ConfigImportRenameValidationTest.php
index fe4df02..5fdc052 100644
--- a/core/modules/config/src/Tests/ConfigImportRenameValidationTest.php
+++ b/core/modules/config/tests/src/Kernel/ConfigImportRenameValidationTest.php
@@ -2,10 +2,10 @@
 
 /**
  * @file
- * Contains \Drupal\config\Tests\ConfigImportRenameValidationTest.
+ * Contains \Drupal\Tests\config\Kernel\ConfigImportRenameValidationTest.
  */
 
-namespace Drupal\config\Tests;
+namespace Drupal\Tests\config\Kernel;
 
 use Drupal\Component\Utility\SafeMarkup;
 use Drupal\Component\Utility\Unicode;
@@ -14,7 +14,7 @@
 use Drupal\Core\Config\ConfigImporterException;
 use Drupal\Core\Config\StorageComparer;
 use Drupal\node\Entity\NodeType;
-use Drupal\simpletest\KernelTestBase;
+use Drupal\KernelTests\KernelTestBase;
 
 /**
  * Tests validating renamed configuration in a configuration import.
diff --git a/core/modules/config/src/Tests/ConfigImporterMissingContentTest.php b/core/modules/config/tests/src/Kernel/ConfigImporterMissingContentTest.php
similarity index 96%
rename from core/modules/config/src/Tests/ConfigImporterMissingContentTest.php
rename to core/modules/config/tests/src/Kernel/ConfigImporterMissingContentTest.php
index e394123..c6dbe88 100644
--- a/core/modules/config/src/Tests/ConfigImporterMissingContentTest.php
+++ b/core/modules/config/tests/src/Kernel/ConfigImporterMissingContentTest.php
@@ -2,15 +2,15 @@
 
 /**
  * @file
- * Contains \Drupal\config\Tests\ConfigImporterMissingContentTest.
+ * Contains \Drupal\Tests\config\Kernel\ConfigImporterMissingContentTest.
  */
 
-namespace Drupal\config\Tests;
+namespace Drupal\Tests\config\Kernel;
 
 use Drupal\Core\Config\ConfigImporter;
 use Drupal\Core\Config\StorageComparer;
 use Drupal\entity_test\Entity\EntityTest;
-use Drupal\simpletest\KernelTestBase;
+use Drupal\KernelTests\KernelTestBase;
 
 /**
  * Tests importing configuration which has missing content dependencies.
diff --git a/core/modules/config/src/Tests/ConfigImporterTest.php b/core/modules/config/tests/src/Kernel/ConfigImporterTest.php
similarity index 99%
rename from core/modules/config/src/Tests/ConfigImporterTest.php
rename to core/modules/config/tests/src/Kernel/ConfigImporterTest.php
index 3fca8c0..a4c3c14 100644
--- a/core/modules/config/src/Tests/ConfigImporterTest.php
+++ b/core/modules/config/tests/src/Kernel/ConfigImporterTest.php
@@ -2,17 +2,17 @@
 
 /**
  * @file
- * Contains \Drupal\config\Tests\ConfigImporterTest.
+ * Contains \Drupal\Tests\config\Kernel\ConfigImporterTest.
  */
 
-namespace Drupal\config\Tests;
+namespace Drupal\Tests\config\Kernel;
 
 use Drupal\Component\Utility\Html;
 use Drupal\Component\Utility\SafeMarkup;
 use Drupal\Core\Config\ConfigImporter;
 use Drupal\Core\Config\ConfigImporterException;
 use Drupal\Core\Config\StorageComparer;
-use Drupal\simpletest\KernelTestBase;
+use Drupal\KernelTests\KernelTestBase;
 
 /**
  * Tests importing configuration from files into active configuration.
diff --git a/core/modules/config/src/Tests/ConfigInstallTest.php b/core/modules/config/tests/src/Kernel/ConfigInstallTest.php
similarity index 98%
rename from core/modules/config/src/Tests/ConfigInstallTest.php
rename to core/modules/config/tests/src/Kernel/ConfigInstallTest.php
index 321b767..09745d1 100644
--- a/core/modules/config/src/Tests/ConfigInstallTest.php
+++ b/core/modules/config/tests/src/Kernel/ConfigInstallTest.php
@@ -2,15 +2,15 @@
 
 /**
  * @file
- * Contains \Drupal\config\Tests\ConfigInstallTest.
+ * Contains \Drupal\Tests\config\Kernel\ConfigInstallTest.
  */
 
-namespace Drupal\config\Tests;
+namespace Drupal\Tests\config\Kernel;
 
 use Drupal\Core\Config\InstallStorage;
 use Drupal\Core\Config\PreExistingConfigException;
 use Drupal\Core\Config\UnmetDependenciesException;
-use Drupal\simpletest\KernelTestBase;
+use Drupal\KernelTests\KernelTestBase;
 
 /**
  * Tests installation of configuration objects in installation functionality.
diff --git a/core/modules/config/src/Tests/ConfigLanguageOverrideTest.php b/core/modules/config/tests/src/Kernel/ConfigLanguageOverrideTest.php
similarity index 97%
rename from core/modules/config/src/Tests/ConfigLanguageOverrideTest.php
rename to core/modules/config/tests/src/Kernel/ConfigLanguageOverrideTest.php
index 8cbb695..20d0519 100644
--- a/core/modules/config/src/Tests/ConfigLanguageOverrideTest.php
+++ b/core/modules/config/tests/src/Kernel/ConfigLanguageOverrideTest.php
@@ -2,13 +2,13 @@
 
 /**
  * @file
- * Contains \Drupal\config\Tests\ConfigLanguageOverrideTest.
+ * Contains \Drupal\Tests\config\Kernel\ConfigLanguageOverrideTest.
  */
 
-namespace Drupal\config\Tests;
+namespace Drupal\Tests\config\Kernel;
 
 use Drupal\language\Entity\ConfigurableLanguage;
-use Drupal\simpletest\KernelTestBase;
+use Drupal\KernelTests\KernelTestBase;
 
 /**
  * Confirm that language overrides work.
diff --git a/core/modules/config/src/Tests/ConfigOverrideTest.php b/core/modules/config/tests/src/Kernel/ConfigOverrideTest.php
similarity index 97%
rename from core/modules/config/src/Tests/ConfigOverrideTest.php
rename to core/modules/config/tests/src/Kernel/ConfigOverrideTest.php
index b9a262d..520af73 100644
--- a/core/modules/config/src/Tests/ConfigOverrideTest.php
+++ b/core/modules/config/tests/src/Kernel/ConfigOverrideTest.php
@@ -2,12 +2,12 @@
 
 /**
  * @file
- * Contains \Drupal\config\Tests\ConfigOverrideTest.
+ * Contains \Drupal\Tests\config\Kernel\ConfigOverrideTest.
  */
 
-namespace Drupal\config\Tests;
+namespace Drupal\Tests\config\Kernel;
 
-use Drupal\simpletest\KernelTestBase;
+use Drupal\KernelTests\KernelTestBase;
 
 /**
  * Tests configuration overrides via $config in settings.php.
diff --git a/core/modules/config/src/Tests/ConfigSchemaTest.php b/core/modules/config/tests/src/Kernel/ConfigSchemaTest.php
similarity index 99%
rename from core/modules/config/src/Tests/ConfigSchemaTest.php
rename to core/modules/config/tests/src/Kernel/ConfigSchemaTest.php
index a89db0e..3b0504e 100644
--- a/core/modules/config/src/Tests/ConfigSchemaTest.php
+++ b/core/modules/config/tests/src/Kernel/ConfigSchemaTest.php
@@ -2,17 +2,17 @@
 
 /**
  * @file
- * Contains \Drupal\config\Tests\ConfigSchemaTest.
+ * Contains \Drupal\Tests\config\Kernel\ConfigSchemaTest.
  */
 
-namespace Drupal\config\Tests;
+namespace Drupal\Tests\config\Kernel;
 
 use Drupal\Core\Config\FileStorage;
 use Drupal\Core\Config\InstallStorage;
 use Drupal\Core\Config\Schema\ConfigSchemaAlterException;
 use Drupal\Core\TypedData\Type\IntegerInterface;
 use Drupal\Core\TypedData\Type\StringInterface;
-use Drupal\simpletest\KernelTestBase;
+use Drupal\KernelTests\KernelTestBase;
 
 /**
  * Tests schema for configuration objects.
diff --git a/core/modules/config/src/Tests/ConfigSnapshotTest.php b/core/modules/config/tests/src/Kernel/ConfigSnapshotTest.php
similarity index 95%
rename from core/modules/config/src/Tests/ConfigSnapshotTest.php
rename to core/modules/config/tests/src/Kernel/ConfigSnapshotTest.php
index cbb67b7..5130428 100644
--- a/core/modules/config/src/Tests/ConfigSnapshotTest.php
+++ b/core/modules/config/tests/src/Kernel/ConfigSnapshotTest.php
@@ -2,13 +2,13 @@
 
 /**
  * @file
- * Contains \Drupal\config\Tests\ConfigSnapshotTest.
+ * Contains \Drupal\Tests\config\Kernel\ConfigSnapshotTest.
  */
 
-namespace Drupal\config\Tests;
+namespace Drupal\Tests\config\Kernel;
 
 use Drupal\Core\Config\StorageComparer;
-use Drupal\simpletest\KernelTestBase;
+use Drupal\KernelTests\KernelTestBase;
 
 /**
  * Tests config snapshot creation and updating.
diff --git a/core/modules/config/src/Tests/DefaultConfigTest.php b/core/modules/config/tests/src/Kernel/DefaultConfigTest.php
similarity index 94%
rename from core/modules/config/src/Tests/DefaultConfigTest.php
rename to core/modules/config/tests/src/Kernel/DefaultConfigTest.php
index 2610c3d..3e72d70 100644
--- a/core/modules/config/src/Tests/DefaultConfigTest.php
+++ b/core/modules/config/tests/src/Kernel/DefaultConfigTest.php
@@ -2,15 +2,15 @@
 
 /**
  * @file
- * Contains \Drupal\config\Tests\DefaultConfigTest.
+ * Contains \Drupal\Tests\config\Kernel\DefaultConfigTest.
  */
 
-namespace Drupal\config\Tests;
+namespace Drupal\Tests\config\Kernel;
 
 use Drupal\config_test\TestInstallStorage;
 use Drupal\Core\Config\InstallStorage;
 use Drupal\Core\DependencyInjection\ContainerBuilder;
-use Drupal\simpletest\KernelTestBase;
+use Drupal\KernelTests\KernelTestBase;
 use Symfony\Component\DependencyInjection\Reference;
 
 /**
diff --git a/core/modules/config/src/Tests/SchemaCheckTraitTest.php b/core/modules/config/tests/src/Kernel/SchemaCheckTraitTest.php
similarity index 93%
rename from core/modules/config/src/Tests/SchemaCheckTraitTest.php
rename to core/modules/config/tests/src/Kernel/SchemaCheckTraitTest.php
index 25d150d..32eed93 100644
--- a/core/modules/config/src/Tests/SchemaCheckTraitTest.php
+++ b/core/modules/config/tests/src/Kernel/SchemaCheckTraitTest.php
@@ -2,13 +2,13 @@
 
 /**
  * @file
- * Contains \Drupal\config\Tests\SchemaCheckTraitTest.
+ * Contains \Drupal\Tests\config\Kernel\SchemaCheckTraitTest.
  */
 
-namespace Drupal\config\Tests;
+namespace Drupal\Tests\config\Kernel;
 
 use Drupal\Core\Config\Schema\SchemaCheckTrait;
-use Drupal\simpletest\KernelTestBase;
+use Drupal\KernelTests\KernelTestBase;
 
 
 /**