43 files declare their use of Extension

advisory_feed_test.module in core/modules/system/tests/modules/advisory_feed_test/advisory_feed_test.module
Module for testing the display of security advisories.
config_translation_test.module in core/modules/config_translation/tests/modules/config_translation_test/config_translation_test.module
Configuration Translation Test module.
dependency_version_test.module in core/modules/system/tests/modules/dependency_version_test/dependency_version_test.module
Module for testing the dependency version comparisons.
deprecated_module_test.module in core/modules/system/tests/modules/deprecated_module_test/deprecated_module_test.module
Deprecated module test module.
DrupalKernel.php in core/lib/Drupal/Core/DrupalKernel.php
ExtensionDiscoveryTest.php in core/tests/Drupal/Tests/Core/Extension/ExtensionDiscoveryTest.php
ExtensionListTest.php in core/tests/Drupal/Tests/Core/Extension/ExtensionListTest.php
ExtensionSerializationTest.php in core/tests/Drupal/Tests/Core/Extension/ExtensionSerializationTest.php
FieldDefinitionIntegrityTest.php in core/modules/field/tests/src/Kernel/FieldDefinitionIntegrityTest.php
GenerateTheme.php in core/lib/Drupal/Core/Command/GenerateTheme.php
InstallerNonDefaultDatabaseDriverTest.php in core/tests/Drupal/FunctionalTests/Installer/InstallerNonDefaultDatabaseDriverTest.php
InstallStorage.php in core/lib/Drupal/Core/Config/InstallStorage.php
LayoutPluginManagerTest.php in core/tests/Drupal/Tests/Core/Layout/LayoutPluginManagerTest.php
LinkRelationTypeManager.php in core/lib/Drupal/Core/Http/LinkRelationTypeManager.php
locale_test.module in core/modules/locale/tests/modules/locale_test/locale_test.module
Simulate a custom module with a local po file.
locale_test_development_release.module in core/modules/locale/tests/modules/locale_test_development_release/locale_test_development_release.module
Simulate a Drupal version.
locale_test_translate.module in core/modules/locale/tests/modules/locale_test_translate/locale_test_translate.module
Simulates a custom module with a local po file.
ModuleHandlerTest.php in core/tests/Drupal/Tests/Core/Extension/ModuleHandlerTest.php
ModulesListForm.php in core/modules/system/src/Form/ModulesListForm.php
module_required_test.module in core/modules/system/tests/modules/module_required_test/module_required_test.module
Test module.
module_test.module in core/modules/system/tests/modules/module_test/module_test.module
Test module.
nyan_cat.engine in core/modules/system/tests/themes/engines/nyan_cat/nyan_cat.engine
Handles integration of Nyan cat templates because we love kittens.
PermissionHandlerTest.php in core/modules/user/tests/src/Unit/PermissionHandlerTest.php
Contains \Drupal\Tests\user\Unit\PermissionHandlerTest.
ProjectInfo.php in core/lib/Drupal/Core/Utility/ProjectInfo.php
ResourceResponseValidatorTest.php in core/modules/jsonapi/tests/src/Unit/EventSubscriber/ResourceResponseValidatorTest.php
SecurityAdvisoriesFetcherTest.php in core/modules/system/tests/src/Kernel/SecurityAdvisories/SecurityAdvisoriesFetcherTest.php
system.module in core/modules/system/system.module
Configuration system that lets administrators modify the workings of the site.
SystemLocalTasksTest.php in core/modules/system/tests/src/Unit/Menu/SystemLocalTasksTest.php
system_test.module in core/modules/system/tests/modules/system_test/system_test.module
Test module.
TestDiscoveryTest.php in core/tests/Drupal/Tests/Core/Test/TestDiscoveryTest.php
TestRunnerKernel.php in core/lib/Drupal/Core/Test/TestRunnerKernel.php
TestRunnerKernelTest.php in core/tests/Drupal/Tests/Core/Test/TestRunnerKernelTest.php
test_module_required_by_theme.module in core/modules/system/tests/themes/test_theme_depending_on_modules/test_module_required_by_theme/test_module_required_by_theme.module
This file provides testing functionality for update.php.
ThemeExtensionListTest.php in core/tests/Drupal/Tests/Core/Extension/ThemeExtensionListTest.php
ThemeHandlerTest.php in core/tests/Drupal/Tests/Core/Extension/ThemeHandlerTest.php
Contains \Drupal\Tests\Core\Extension\ThemeHandlerTest.
ThemeInitialization.php in core/lib/Drupal/Core/Theme/ThemeInitialization.php
ThemeInitializationInterface.php in core/lib/Drupal/Core/Theme/ThemeInitializationInterface.php
theme_page_test.module in core/modules/system/tests/modules/theme_page_test/theme_page_test.module
Test module.
theme_test.module in core/modules/system/tests/modules/theme_test/theme_test.module
Test module.
twig.engine in core/themes/engines/twig/twig.engine
Handles integration of Twig templates with the Drupal theme system.
UpdateRegistry.php in core/lib/Drupal/Core/Update/UpdateRegistry.php
update_script_test.module in core/modules/system/tests/modules/update_script_test/update_script_test.module
This file provides testing functionality for update.php.
update_test.module in core/modules/update/tests/modules/update_test/update_test.module
Module for testing Update Manager functionality.

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