161 string references to 'system.theme' in Drupal 10

AdminAjaxTest::testAjaxRebuild in core/modules/views_ui/tests/src/FunctionalJavascript/AdminAjaxTest.php

Confirms that form_alter is triggered after AJAX rebuilds.

AdminNegotiator::determineActiveTheme in core/modules/user/src/Theme/AdminNegotiator.php

AdminNegotiatorTest::testDetermineActiveTheme in core/modules/user/tests/src/Unit/Theme/AdminNegotiatorTest.php

@dataProvider getThemes

AjaxBasePageNegotiator::determineActiveTheme in core/lib/Drupal/Core/Theme/AjaxBasePageNegotiator.php

AjaxBasePageNegotiatorTest::setUp in core/tests/Drupal/Tests/Core/Theme/AjaxBasePageNegotiatorTest.php

AjaxTest::testAjaxWithAdminRoute in core/tests/Drupal/FunctionalJavascriptTests/Ajax/AjaxTest.php

AreaEntityTest::setUpFixtures in core/modules/views/tests/src/Kernel/Handler/AreaEntityTest.php

BaseThemeRequiredTest::testWildWest in core/tests/Drupal/KernelTests/Core/Theme/BaseThemeRequiredTest.php

Tests opting out of Stable by setting the base theme to false.

BasicTest::testViewsWizardAndListing in core/modules/views/tests/src/Functional/Wizard/BasicTest.php

BigPipeRegressionTest::setUp in core/modules/big_pipe/tests/src/FunctionalJavascript/BigPipeRegressionTest.php

BigPipeRegressionTest::setUp in core/modules/ckeditor/tests/src/FunctionalJavascript/BigPipeRegressionTest.php

BlockContentCreationTest::testBlockDelete in core/modules/block_content/tests/src/Functional/BlockContentCreationTest.php

Tests deleting a block.

BlockContentCreationTest::testConfigDependencies in core/modules/block_content/tests/src/Functional/BlockContentCreationTest.php

Tests placed content blocks create a dependency in the block placement.

BlockContentForm::save in core/modules/block_content/src/BlockContentForm.php

Form submission handler for the 'save' action.

BlockContentLocalTasksTest::setUp in core/modules/block_content/tests/src/Unit/Menu/BlockContentLocalTasksTest.php

BlockContentTypeTest::testsBlockContentAddTypes in core/modules/block_content/tests/src/Functional/BlockContentTypeTest.php

Tests that redirects work as expected when multiple block types exist.

BlockCreationTrait::placeBlock in core/modules/block/tests/src/Traits/BlockCreationTrait.php

Creates a block instance based on default settings.

BlockDemoTest::testBlockDemo in core/modules/block/tests/src/Functional/BlockDemoTest.php

Check for the accessibility of the admin block demo page.

BlockDependenciesTest::createBlock in core/modules/views/tests/src/Kernel/Plugin/BlockDependenciesTest.php

Creates a block instance based on default settings.

BlockForm::form in core/modules/block/src/BlockForm.php

Gets the actual form array to be built.

BlockHiddenRegionTest::testBlockNotInHiddenRegion in core/modules/block/tests/src/Functional/BlockHiddenRegionTest.php

Tests that hidden regions do not inherit blocks when a theme is installed.

BlockLanguageTest::testLanguageBlockVisibility in core/modules/block/tests/src/Functional/BlockLanguageTest.php

Tests the visibility settings for the blocks based on language.

BlockLanguageTest::testMultipleLanguageTypes in core/modules/block/tests/src/Functional/BlockLanguageTest.php

Tests block language visibility with different language types.

BlockListController::listing in core/modules/block/src/Controller/BlockListController.php

Shows the block administration page.

BlockLocalTasksTest::setUp in core/modules/block/tests/src/Unit/Menu/BlockLocalTasksTest.php

BlockRebuildTest::setUp in core/modules/block/tests/src/Kernel/BlockRebuildTest.php

BlockTest::moveBlockToRegion in core/modules/block/tests/src/Functional/BlockTest.php

Moves a block to a given region via the UI and confirms the result.

BlockTest::testAddBlockFromLibraryWithWeight in core/modules/block/tests/src/Functional/BlockTest.php

Tests adding a block from the library page with a weight query string.

BlockTest::testBlock in core/modules/block/tests/src/Functional/BlockTest.php

Tests configuring and moving a module-define block to specific regions.

BlockTest::testBlockThemeSelector in core/modules/block/tests/src/Functional/BlockTest.php

Tests that the block form has a theme selector when not passed via the URL.

BlockTest::testBlockTitle in core/modules/block/tests/src/Functional/BlockTest.php

Tests block title.

BlockTest::testBlockToggleVisibility in core/modules/block/tests/src/Functional/BlockTest.php

Tests that visibility can be properly toggled.

BlockTest::testBlockVisibility in core/modules/block/tests/src/Functional/BlockTest.php

Tests block visibility.

BlockTest::testBlockVisibilityListedEmpty in core/modules/block/tests/src/Functional/BlockTest.php

Tests block visibility when leaving "pages" textarea empty.

BlockTest::testHideBlockTitle in core/modules/block/tests/src/Functional/BlockTest.php

Tests block title display settings.

BlockTest::testUninstallTheme in core/modules/block/tests/src/Functional/BlockTest.php

Tests that uninstalling a theme removes its block configuration.

BlockTestBase::setUp in core/modules/block/tests/src/Functional/BlockTestBase.php

BlockTheme::create in core/modules/block/src/Plugin/migrate/process/BlockTheme.php

Creates an instance of the plugin.

BlockUiTest::testBlockAdminUiPage in core/modules/block/tests/src/Functional/BlockUiTest.php

Tests block admin page exists and functions correctly.

BlockXssTest::testXssInTitle in core/modules/block/tests/src/Functional/BlockXssTest.php

Tests XSS in title.

block_help in core/modules/block/block.module

Implements hook_help().

block_page_top in core/modules/block/block.module

Implements hook_page_top().

block_theme_initialize in core/modules/block/block.module

Assigns an initial, default set of blocks for a theme.

BreadcrumbTest::setUp in core/modules/system/tests/src/Functional/Menu/BreadcrumbTest.php

CacheabilityMetadataConfigOverrideTest::testConfigOverride in core/tests/Drupal/KernelTests/Core/Config/CacheabilityMetadataConfigOverrideTest.php

Tests if config overrides correctly set cacheability metadata.

CKEditor5CacheTag::onSave in core/modules/ckeditor5/src/EventSubscriber/CKEditor5CacheTag.php

Invalidates cache tags when particular system config objects are saved.

CKEditor5StylesheetsMessage::getWarning in core/modules/ckeditor5/src/CKEditor5StylesheetsMessage.php

Generates a warning related to ckeditor_stylesheets.

CKEditor5StylesheetsTest::testExternalStylesheets in core/modules/ckeditor5/tests/src/Kernel/CKEditor5StylesheetsTest.php

Tests loading of theme's CKEditor 5 stylesheets defined in the .info file.

CKEditorStylesheetsWarningTest::installThemeThatTriggersWarning in core/modules/ckeditor5/tests/src/FunctionalJavascript/CKEditorStylesheetsWarningTest.php

Installs and enables themes for testing.

CKEditorTest::testBuildContentsCssJSSetting in core/modules/ckeditor/tests/src/Kernel/CKEditorTest.php

Tests CKEditor::buildContentsCssJSSetting().

CKEditorTest::testExternalStylesheets in core/modules/ckeditor/tests/src/Kernel/CKEditorTest.php

Tests loading of theme's CKEditor stylesheets defined in the .info file.

ClaroBlockFilterTest::setUp in core/tests/Drupal/FunctionalJavascriptTests/Theme/ClaroBlockFilterTest.php

ClaroEntityDisplayTest::setUp in core/tests/Drupal/FunctionalJavascriptTests/Theme/ClaroEntityDisplayTest.php

ClaroMenuUiJavascriptTest::setUp in core/tests/Drupal/FunctionalJavascriptTests/Theme/ClaroMenuUiJavascriptTest.php

ClaroVerticalTabsTest::testVerticalTabs in core/tests/Drupal/KernelTests/Core/Theme/ClaroVerticalTabsTest.php

Confirms that Claro can render vertical tabs correctly.

ClassyTest::setUp in core/modules/system/tests/src/Kernel/Render/ClassyTest.php

CommentLinksTest::testCommentLinks in core/modules/comment/tests/src/Functional/CommentLinksTest.php

Tests that comment links are output and can be hidden.

ConfigCacheTag::onSave in core/modules/system/src/EventSubscriber/ConfigCacheTag.php

Invalidate cache tags when particular system config objects are saved.

ConfigImporter::processExtension in core/lib/Drupal/Core/Config/ConfigImporter.php

Processes an extension change.

ConfigImportInstallProfileTest::testInstallProfileValidation in core/modules/config/tests/src/Functional/ConfigImportInstallProfileTest.php

Tests config importer cannot uninstall install profiles.

ConfigImportUITest::testImport in core/modules/config/tests/src/Functional/ConfigImportUITest.php

Tests importing configuration.

ConfigureBlockFormBase::doBuildForm in core/modules/layout_builder/src/Form/ConfigureBlockFormBase.php

Builds the form for the block.

CurrentThemeConditionTest::testCurrentTheme in core/tests/Drupal/KernelTests/Core/Plugin/Condition/CurrentThemeConditionTest.php

Tests the current theme condition.

CustomBooleanTest::testCustomOptionTemplate in core/modules/views_ui/tests/src/Functional/CustomBooleanTest.php

Tests the setting and output of custom labels for boolean values.

DefaultNegotiator::determineActiveTheme in core/lib/Drupal/Core/Theme/DefaultNegotiator.php

DisplayApiTest::testFieldItemListView in core/modules/field/tests/src/Kernel/DisplayApiTest.php

Tests the FieldItemListInterface::view() method.

DisplayBlockTest::testViewsBlockForm in core/modules/block/tests/src/Functional/Views/DisplayBlockTest.php

Tests the block form for a Views block.

EngineNyanCatTest::testTemplateOverride in core/modules/system/tests/src/Functional/Theme/EngineNyanCatTest.php

Ensures a theme's template is overridable based on the 'template' filename.

EngineTwigTest::testTwigVariableDataTypes in core/modules/system/tests/src/Functional/Theme/EngineTwigTest.php

Tests that the Twig engine handles PHP data correctly.

EntityFilteringThemeTest::testThemedEntity in core/modules/system/tests/src/Functional/Theme/EntityFilteringThemeTest.php

Checks each themed entity for XSS filtering in available themes.

EntityReferenceFormatterTest::setUp in core/modules/field/tests/src/Kernel/EntityReference/EntityReferenceFormatterTest.php

ExperimentalThemeTest::testExperimentalConfirmForm in core/modules/system/tests/src/Functional/Theme/ExperimentalThemeTest.php

Tests installing experimental themes and dependencies in the UI.

ExposedFilterAJAXTest::testExposedFilteringWithButtonElement in core/modules/views/tests/src/FunctionalJavascript/ExposedFilterAJAXTest.php

Tests exposed filtering via AJAX with a button element.

ExposedFormCheckboxesTest::testExposedFormRenderCheckboxes in core/modules/views/tests/src/Functional/Plugin/ExposedFormCheckboxesTest.php

Tests overriding the default render option with checkboxes.

ExposedFormCheckboxesTest::testExposedIsAllOfFilter in core/modules/views/tests/src/Functional/Plugin/ExposedFormCheckboxesTest.php

Tests that "is all of" filters work with checkboxes.

FrameworkTest::testLazyLoadOverriddenCSS in core/modules/system/tests/src/FunctionalJavascript/FrameworkTest.php

Tests that overridden CSS files are not added during lazy load.

FunctionalTestSetupTrait::installDefaultThemeFromClassProperty in core/lib/Drupal/Core/Test/FunctionalTestSetupTrait.php

Installs the default theme defined by `static::$defaultTheme` when needed.

FunctionsTest::setUp in core/modules/system/tests/src/Kernel/Theme/FunctionsTest.php

HelpTopicTranslatedTestBase::setUp in core/modules/help_topics/tests/src/Functional/HelpTopicTranslatedTestBase.php

ItemsPerPageTest::testItemsPerPage in core/modules/views/tests/src/Functional/Wizard/ItemsPerPageTest.php

Tests the number of items per page.

JsMessageTest::setUp in core/tests/Drupal/FunctionalJavascriptTests/Core/JsMessageTest.php

LayoutBuilderCompatibilityTestBase::setUp in core/modules/layout_builder/tests/src/Kernel/LayoutBuilderCompatibilityTestBase.php

LayoutTest::testThemeProvidedLayout in core/modules/layout_discovery/tests/src/Kernel/LayoutTest.php

Tests that a layout provided by a theme has the preprocess function set.

MediaTest::testErrorMessages in core/modules/ckeditor/tests/src/FunctionalJavascript/MediaTest.php

Tests that failed media embed preview requests inform the end user.

MediaTest::testErrorMessages in core/modules/ckeditor5/tests/src/FunctionalJavascript/MediaTest.php

Tests that failed media embed preview requests inform the end user.

MediaTest::testPreviewUsesDefaultThemeAndIsClientCacheable in core/modules/ckeditor/tests/src/FunctionalJavascript/MediaTest.php

The CKEditor Widget must load a preview generated using the default theme.

MediaTest::testPreviewUsesDefaultThemeAndIsClientCacheable in core/modules/ckeditor5/tests/src/FunctionalJavascript/MediaTest.php

The CKEditor Widget must load a preview generated using the default theme.

MenuRouterTest::testThemeIntegration in core/modules/system/tests/src/Functional/Menu/MenuRouterTest.php

Tests theme integration.

MenuUiJavascriptTest::addCustomMenu in core/modules/menu_ui/tests/src/FunctionalJavascript/MenuUiJavascriptTest.php

Creates a custom menu.

MenuUiTest::addCustomMenu in core/modules/menu_ui/tests/src/Functional/MenuUiTest.php

Creates a custom menu.

MenuUiTest::testSystemMenuRename in core/modules/menu_ui/tests/src/Functional/MenuUiTest.php

Tests renaming the built-in menu.

MessageTest::testMessages in core/tests/Drupal/KernelTests/Core/Theme/MessageTest.php

Tests setting messages output.

MigrateBlockTest::setUp in core/modules/block/tests/src/Kernel/Migrate/d6/MigrateBlockTest.php

MigrateBlockTest::setUp in core/modules/block/tests/src/Kernel/Migrate/d7/MigrateBlockTest.php

ModerationStateBlockTest::testCustomBlockModeration in core/modules/content_moderation/tests/src/Functional/ModerationStateBlockTest.php

Tests moderating custom blocks.

NewDefaultThemeBlocksTest::testNewDefaultThemeBlocks in core/modules/block/tests/src/Kernel/NewDefaultThemeBlocksTest.php

Check the blocks are correctly copied by block_themes_installed().

NodeDisplayConfigurableTest::setUp in core/modules/node/tests/src/Functional/NodeDisplayConfigurableTest.php

NumberFieldRdfaTest::testDecimalFormatterWithSettings in core/modules/rdf/tests/src/Kernel/Field/NumberFieldRdfaTest.php

Tests the decimal formatter with settings.

NumberFieldRdfaTest::testFloatFormatterWithScaleExercised in core/modules/rdf/tests/src/Kernel/Field/NumberFieldRdfaTest.php

Tests the float formatter with a scale. Scale is exercised.

NumberFieldRdfaTest::testFloatFormatterWithSettings in core/modules/rdf/tests/src/Kernel/Field/NumberFieldRdfaTest.php

Tests the float formatter with settings.

NumberFieldRdfaTest::testIntegerFormatterWithSettings in core/modules/rdf/tests/src/Kernel/Field/NumberFieldRdfaTest.php

Tests the integer formatter with settings.

OffCanvasTestBase::enableTheme in core/modules/system/tests/src/FunctionalJavascript/OffCanvasTestBase.php

Enables a theme.

OliveroMessagesTest::setUp in core/tests/Drupal/FunctionalJavascriptTests/Theme/OliveroMessagesTest.php

OverrideDisplaysTest::testOverrideDisplays in core/modules/views_ui/tests/src/Functional/OverrideDisplaysTest.php

Tests that displays can be overridden via the UI.

OverrideDisplaysTest::testWizardMixedDefaultOverriddenDisplays in core/modules/views_ui/tests/src/Functional/OverrideDisplaysTest.php

Tests that the wizard correctly sets up default and overridden displays.

PageTest::testBatchProgressPageTheme in core/modules/system/tests/src/Functional/Batch/PageTest.php

Tests that the batch API progress page uses the correct theme.

PirateDayCacheabilityMetadataConfigOverride::loadOverrides in core/modules/config/tests/config_override_test/src/PirateDayCacheabilityMetadataConfigOverride.php

QuickEditMinimalTest::testSuccessfulInstall in core/modules/quickedit/tests/src/Functional/QuickEditMinimalTest.php

Tests that Quick Edit works with no admin theme.

quickedit_library_info_alter in core/modules/quickedit/quickedit.module

Implements hook_library_info_alter().

RegistryTest::testThemeRegistryAlterByTheme in core/tests/Drupal/KernelTests/Core/Theme/RegistryTest.php

Tests that the theme registry can be altered by themes.

SearchAdminThemeTest::setUp in core/modules/search/tests/src/Functional/SearchAdminThemeTest.php

ShortcutLinksTest::testAccessShortcutsPermission in core/modules/shortcut/tests/src/Functional/ShortcutLinksTest.php

Tests that the 'access shortcuts' permissions works properly.

ShortcutLinksTest::testNoShortcutLink in core/modules/shortcut/tests/src/Functional/ShortcutLinksTest.php

Tests that the add shortcut link is not displayed for 404/403 errors.

ShortcutLinksTest::testShortcutQuickLink in core/modules/shortcut/tests/src/Functional/ShortcutLinksTest.php

Tests that the "add to shortcut" and "remove from shortcut" links work.

StatisticsAttachedTest::setUp in core/modules/statistics/tests/src/Functional/StatisticsAttachedTest.php

SystemConfigSubscriber::onConfigSave in core/modules/system/src/SystemConfigSubscriber.php

Rebuilds the router when the default or admin theme is changed.

SystemController::themesPage in core/modules/system/src/Controller/SystemController.php

Returns a theme listing which excludes obsolete themes.

TableTest::testThemeTableWithEmptyMessage in core/tests/Drupal/KernelTests/Core/Render/Element/TableTest.php

Tests that the table header is printed correctly even if there are no rows, and that the empty text is displayed correctly.

TestSiteOliveroInstallTestScript::setup in core/tests/Drupal/TestSite/TestSiteOliveroInstallTestScript.php

TestThemeNegotiator::determineActiveTheme in core/modules/system/tests/modules/menu_test/src/Theme/TestThemeNegotiator.php

Determine the active theme for the request.

ThemeAdminForm::buildForm in core/modules/system/src/Form/ThemeAdminForm.php

Form constructor.

ThemeAdminForm::getEditableConfigNames in core/modules/system/src/Form/ThemeAdminForm.php

Gets the configuration names that will be editable.

ThemeAdminForm::submitForm in core/modules/system/src/Form/ThemeAdminForm.php

Form submission handler.

ThemeController::setDefaultTheme in core/modules/system/src/Controller/ThemeController.php

Set the default theme.

ThemeController::uninstall in core/modules/system/src/Controller/ThemeController.php

Uninstalls a theme.

ThemeExperimentalConfirmForm::submitForm in core/modules/system/src/Form/ThemeExperimentalConfirmForm.php

Form submission handler.

ThemeHandler::getDefault in core/lib/Drupal/Core/Extension/ThemeHandler.php

Returns the default theme.

ThemeHandler::hasUi in core/lib/Drupal/Core/Extension/ThemeHandler.php

Determines if a theme should be shown in the user interface.

ThemeInfoTest::testChanges in core/modules/system/tests/src/Functional/Theme/ThemeInfoTest.php

Tests that changes to the info file are picked up.

ThemeInfoTest::testStylesheets in core/modules/system/tests/src/Functional/Theme/ThemeInfoTest.php

Tests libraries-override.

ThemeInstaller::uninstall in core/lib/Drupal/Core/Extension/ThemeInstaller.php

ThemeInstallerTest::testUninstallAdmin in core/tests/Drupal/KernelTests/Core/Theme/ThemeInstallerTest.php

Tests uninstalling the admin theme.

ThemeInstallerTest::testUninstallDefault in core/tests/Drupal/KernelTests/Core/Theme/ThemeInstallerTest.php

Tests uninstalling the default theme.

ThemeSettingsTest::testLogoConfig in core/tests/Drupal/KernelTests/Core/Theme/ThemeSettingsTest.php

Tests that the default logo config can be overridden.

ThemeSuggestionsAlterTest::testExecutionOrder in core/modules/system/tests/src/Functional/Theme/ThemeSuggestionsAlterTest.php

Tests execution order of theme suggestion alter hooks.

ThemeSuggestionsAlterTest::testGeneralSuggestionsAlter in core/modules/system/tests/src/Functional/Theme/ThemeSuggestionsAlterTest.php

Tests hook_theme_suggestions_alter().

ThemeSuggestionsAlterTest::testSpecificSuggestionsAlter in core/modules/system/tests/src/Functional/Theme/ThemeSuggestionsAlterTest.php

Tests that theme suggestion alter hooks work for specific theme calls.

ThemeSuggestionsAlterTest::testTemplateSuggestions in core/modules/system/tests/src/Functional/Theme/ThemeSuggestionsAlterTest.php

Tests that hooks to provide theme suggestions work.

ThemeSuggestionsAlterTest::testTemplateSuggestionsAlter in core/modules/system/tests/src/Functional/Theme/ThemeSuggestionsAlterTest.php

Tests that theme suggestion alter hooks work for templates.

ThemeTest::setUp in core/modules/taxonomy/tests/src/Functional/ThemeTest.php

ThemeTest::testClassLoading in core/modules/system/tests/src/Functional/Theme/ThemeTest.php

Tests theme can provide classes.

ThemeTest::testSuggestionPreprocessForDefaults in core/modules/system/tests/src/Functional/Theme/ThemeTest.php

Ensures suggestion preprocess functions run for default implementations.

ThemeTest::testTemplateOverride in core/modules/system/tests/src/Functional/Theme/ThemeTest.php

Ensures a themes template is overridable based on the 'template' filename.

ThemeTokenTest::testThemeToken in core/modules/system/tests/src/Functional/Theme/ThemeTokenTest.php

Tests if the 'theme_token' key of 'ajaxPageState' is computed.

TourTestBasic::setUp in core/modules/tour/tests/src/Functional/TourTestBasic.php

TwigDebugMarkupTest::testTwigDebugMarkup in core/modules/system/tests/src/Functional/Theme/TwigDebugMarkupTest.php

Tests debug markup added to Twig template output.

TwigExtensionTest::testTwigExtensionFilter in core/modules/system/tests/src/Functional/Theme/TwigExtensionTest.php

Tests that the Twig extension's filter produces expected output.

TwigExtensionTest::testTwigExtensionFunction in core/modules/system/tests/src/Functional/Theme/TwigExtensionTest.php

Tests that the Twig extension's function produces expected output.

TwigRegistryLoaderTest::testTwigNamespaces in core/modules/system/tests/src/Functional/Theme/TwigRegistryLoaderTest.php

Tests template extension and includes using the Drupal theme registry.

TwigSettingsTest::testTwigCacheOverride in core/modules/system/tests/src/Functional/Theme/TwigSettingsTest.php

Ensures Twig template cache setting can be overridden.

TwigTransTest::setUp in core/modules/system/tests/src/Functional/Theme/TwigTransTest.php

UserBatchActionTest::testUserAction in core/modules/views/tests/src/Functional/UserBatchActionTest.php

Tests user admin batch.

ViewsEscapingTest::testViewsViewFieldsEscaping in core/modules/views/tests/src/Functional/ViewsEscapingTest.php

Tests for incorrectly escaped markup in the views-view-fields.html.twig.

ViewsNoResultsBehaviorTest::setUp in core/modules/views/tests/src/Functional/ViewsNoResultsBehaviorTest.php

ViewsPreprocessTest::testCssClassCleaning in core/modules/views/tests/src/Kernel/ViewsPreprocessTest.php

Tests css classes on displays are cleaned correctly.

ViewsThemeIntegrationTest::testThemedViewPage in core/modules/views/tests/src/Functional/ViewsThemeIntegrationTest.php

Tests for exceptions and successful execution of hook_views_pre_render() and hook_views_post_render() in theme and subtheme.

WhosOnlineBlockTest::setUp in core/modules/user/tests/src/Kernel/WhosOnlineBlockTest.php

_ckeditor5_theme_css in core/modules/ckeditor5/ckeditor5.module

Retrieves the default theme's CKEditor 5 stylesheets.

_ckeditor_theme_css in core/modules/ckeditor/ckeditor.module

Retrieves the default theme's CKEditor stylesheets.

_drupal_maintenance_theme in core/includes/theme.maintenance.inc

Sets up the theming system for maintenance page.

_system_is_claro_admin_and_not_active in core/modules/system/system.module

Determines if Claro is the admin theme but not the active theme.