Issue #2232605 by alexpott, dawehner, martin107, Cottser, sun: Fixed Themes cannot be uninstalled.

core/config/install/core.extension.yml

 module: {}
 theme: {}
-disabled:
-  theme: {}

core/config/schema/core.extension.schema.yml

@@ -10,17 +10,7 @@ core.extension:
           label: 'Weight'
     theme:
       type: sequence
-      label: 'Enabled themes'
+      label: 'Installed themes'
       sequence:
         - type: integer
           label: 'Weight'
-    disabled:
-      type: mapping
-      label: 'Disabled extensions'
-      mapping:
-        theme:
-          type: sequence
-          label: 'Disabled themes'
-          sequence:
-            - type: integer
-              label: 'Weight'

core/core.services.yml

@@ -283,7 +283,7 @@ services:
     arguments: ['%container.modules%', '@cache.bootstrap']
   theme_handler:
     class: Drupal\Core\Extension\ThemeHandler
-    arguments: ['@config.factory', '@module_handler', '@state', '@info_parser', '@logger.channel.default', '@asset.css.collection_optimizer', '@config.installer', '@router.builder']
+    arguments: ['@config.factory', '@module_handler', '@state', '@info_parser', '@logger.channel.default', '@asset.css.collection_optimizer', '@config.installer', '@config.manager', '@router.builder']
   entity.manager:
     class: Drupal\Core\Entity\EntityManager
     arguments: ['@container.namespaces', '@module_handler', '@cache.discovery', '@language_manager', '@string_translation', '@class_resolver', '@typed_data_manager', '@entity.definitions.installed']

core/includes/install.core.inc

@@ -1512,7 +1512,7 @@ function install_profile_modules(&$install_state) {
  * Installs themes.
  *
  * This does not use a batch, since installing themes is faster than modules and
- * because an installation profile typically enables 1-3 themes only (default
+ * because an installation profile typically installs 1-3 themes only (default
  * theme, base theme, admin theme).
  *
  * @param $install_state
@@ -1521,15 +1521,15 @@ function install_profile_modules(&$install_state) {
 function install_profile_themes(&$install_state) {
   $theme_handler = \Drupal::service('theme_handler');
 
-  // ThemeHandler::enable() resets the current list of themes. The theme used in
-  // the installer is not necessarily in the list of themes to install, so
+  // ThemeHandler::install() resets the current list of themes. The theme used
+  // in the installer is not necessarily in the list of themes to install, so
   // retain the current list.
   // @see _drupal_maintenance_theme()
   $current_themes = $theme_handler->listInfo();
 
   // Install the themes specified by the installation profile.
   $themes = $install_state['profile_info']['themes'];
-  $theme_handler->enable($themes);
+  $theme_handler->install($themes);
 
   foreach ($current_themes as $theme) {
     $theme_handler->addTheme($theme);

core/includes/module.inc

@@ -9,11 +9,11 @@
 use Drupal\Core\Extension\ExtensionDiscovery;
 
 /**
- * Builds a list of enabled themes.
+ * Builds a list of installed themes.
  *
  * @param $type
  *   The type of list to return:
- *   - theme: All enabled themes.
+ *   - theme: All installed themes.
  *
  * @return
  *   An associative array of themes, keyed by name.

core/includes/theme.inc

@@ -77,7 +77,7 @@
  *   Either the name of a theme or a full theme object.
  *
  * @return bool
- *   Boolean TRUE if the theme is enabled or is the site administration theme;
+ *   Boolean TRUE if the theme is installed or is the site administration theme;
  *   FALSE otherwise.
  *
  * @deprecated in Drupal 8.x-dev, will be removed before Drupal 8.0.
@@ -765,42 +765,6 @@ function theme_settings_convert_to_config(array $theme_settings, Config $config)
   return $config;
 }
 
-/**
- * Enables a given list of themes.
- *
- * @param $theme_list
- *   An array of theme names.
- *
- * @return bool
- *   Whether any of the given themes have been enabled.
- *
- * @deprecated in Drupal 8.x-dev, will be removed before Drupal 8.0.
- *   Use \Drupal::service('theme_handler')->enable().
- *
- * @see \Drupal\Core\Extension\ThemeHandler::enable().
- */
-function theme_enable($theme_list) {
-  return \Drupal::service('theme_handler')->enable($theme_list);
-}
-
-/**
- * Disables a given list of themes.
- *
- * @param $theme_list
- *   An array of theme names.
- *
- * @return bool
- *   Whether any of the given themes have been disabled.
- *
- * @deprecated in Drupal 8.x-dev, will be removed before Drupal 8.0.
- *   Use \Drupal::service('theme_handler')->disable().
- *
- * @see \Drupal\Core\Extension\ThemeHandler::disable().
- */
-function theme_disable($theme_list) {
-  return \Drupal::service('theme_handler')->disable($theme_list);
-}
-
 /**
  * @addtogroup themeable
  * @{

core/includes/update.inc

@@ -23,9 +23,6 @@ function update_fix_compatibility() {
     foreach ($extension_config->get($type) as $name => $weight) {
       if (update_check_incompatibility($name, $type)) {
         $extension_config->clear("$type.$name");
-        if ($type === 'theme') {
-          $extension_config->set("disabled.theme.$name", 0);
-        }
         $save = TRUE;
       }
     }

core/lib/Drupal/Core/Config/ConfigImporter.php

@@ -124,7 +124,7 @@ class ConfigImporter {
   protected $themeHandler;
 
   /**
-   * Flag set to import system.theme during processing theme enable and disables.
+   * Flag set to import system.theme during processing theme install and uninstalls.
    *
    * @var bool
    */
@@ -252,8 +252,8 @@ protected function getEmptyExtensionsProcessedList() {
         'uninstall' => array(),
       ),
       'theme' => array(
-        'enable' => array(),
-        'disable' => array(),
+        'install' => array(),
+        'uninstall' => array(),
       ),
     );
   }
@@ -395,9 +395,9 @@ protected function createExtensionChangelist() {
     $module_list = array_reverse($module_list);
     $install = array_intersect(array_keys($module_list), $install);
 
-    // Work out what themes to enable and to disable.
-    $enable = array_diff(array_keys($new_extensions['theme']), array_keys($current_extensions['theme']));
-    $disable = array_diff(array_keys($current_extensions['theme']), array_keys($new_extensions['theme']));
+    // Work out what themes to install and to uninstall.
+    $theme_install = array_diff(array_keys($new_extensions['theme']), array_keys($current_extensions['theme']));
+    $theme_uninstall = array_diff(array_keys($current_extensions['theme']), array_keys($new_extensions['theme']));
 
     $this->extensionChangelist = array(
       'module' => array(
@@ -405,8 +405,8 @@ protected function createExtensionChangelist() {
         'install' => $install,
       ),
       'theme' => array(
-        'enable' => $enable,
-        'disable' => $disable,
+        'install' => $theme_install,
+        'uninstall' => $theme_uninstall,
       ),
     );
   }
@@ -441,20 +441,10 @@ protected function getExtensionChangelist($type, $op = NULL) {
    */
   protected function getUnprocessedExtensions($type) {
     $changelist = $this->getExtensionChangelist($type);
-
-    if ($type == 'theme') {
-      $unprocessed = array(
-        'enable' => array_diff($changelist['enable'], $this->processedExtensions[$type]['enable']),
-        'disable' => array_diff($changelist['disable'], $this->processedExtensions[$type]['disable']),
-      );
-    }
-    else {
-      $unprocessed = array(
-        'install' => array_diff($changelist['install'], $this->processedExtensions[$type]['install']),
-        'uninstall' => array_diff($changelist['uninstall'], $this->processedExtensions[$type]['uninstall']),
-      );
-    }
-    return $unprocessed;
+    return array(
+      'install' => array_diff($changelist['install'], $this->processedExtensions[$type]['install']),
+      'uninstall' => array_diff($changelist['uninstall'], $this->processedExtensions[$type]['uninstall']),
+    );
   }
 
   /**
@@ -533,7 +523,7 @@ public function initialize() {
       $this->totalExtensionsToProcess += count($modules[$op]);
     }
     $themes = $this->getUnprocessedExtensions('theme');
-    foreach (array('enable', 'disable') as $op) {
+    foreach (array('install', 'uninstall') as $op) {
       $this->totalExtensionsToProcess += count($themes[$op]);
     }
 
@@ -576,7 +566,7 @@ protected function processExtensions(array &$context) {
       $this->processExtension($operation['type'], $operation['op'], $operation['name']);
       $context['message'] = t('Synchronising extensions: @op @name.', array('@op' => $operation['op'], '@name' => $operation['name']));
       $processed_count = count($this->processedExtensions['module']['install']) + count($this->processedExtensions['module']['uninstall']);
-      $processed_count += count($this->processedExtensions['theme']['disable']) + count($this->processedExtensions['theme']['enable']);
+      $processed_count += count($this->processedExtensions['theme']['uninstall']) + count($this->processedExtensions['theme']['install']);
       $context['finished'] = $processed_count / $this->totalExtensionsToProcess;
     }
     else {
@@ -650,24 +640,16 @@ protected function finish(array &$context) {
    *   on. If there is nothing left to do returns FALSE;
    */
   protected function getNextExtensionOperation() {
-    foreach (array('install', 'uninstall') as $op) {
-      $modules = $this->getUnprocessedExtensions('module');
-      if (!empty($modules[$op])) {
-        return array(
-          'op' => $op,
-          'type' => 'module',
-          'name' => array_shift($modules[$op]),
-        );
-      }
-    }
-    foreach (array('enable', 'disable') as $op) {
-      $themes = $this->getUnprocessedExtensions('theme');
-      if (!empty($themes[$op])) {
-        return array(
-          'op' => $op,
-          'type' => 'theme',
-          'name' => array_shift($themes[$op]),
-        );
+    foreach (array('module', 'theme') as $type) {
+      foreach (array('install', 'uninstall') as $op) {
+        $unprocessed = $this->getUnprocessedExtensions($type);
+        if (!empty($unprocessed[$op])) {
+          return array(
+            'op' => $op,
+            'type' => $type,
+            'name' => array_shift($unprocessed[$op]),
+          );
+        }
       }
     }
     return FALSE;
@@ -794,11 +776,11 @@ protected function processExtension($type, $op, $name) {
       $this->moduleHandler->loadAll();
     }
     if ($type == 'theme') {
-      // Theme disables possible remove default or admin themes therefore we
-      // need to import this before doing any. If there are no disables and
-      // the default or admin theme is change this will be picked up whilst
+      // Theme uninstalls possible remove default or admin themes therefore we
+      // need to import this before doing any. If there are no uninstalls and
+      // the default or admin theme is changing this will be picked up whilst
       // processing configuration.
-      if ($op == 'disable' && $this->processedSystemTheme === FALSE) {
+      if ($op == 'uninstall' && $this->processedSystemTheme === FALSE) {
         $this->importConfig(StorageInterface::DEFAULT_COLLECTION, 'update', 'system.theme');
         $this->configManager->getConfigFactory()->reset('system.theme');
         $this->processedSystemTheme = TRUE;

core/lib/Drupal/Core/Extension/ThemeHandlerInterface.php

@@ -8,49 +8,54 @@
 namespace Drupal\Core\Extension;
 
 /**
- * Manages the list of available themes as well as enable/disable them.
+ * Manages the list of available themes as well as install/uninstall them.
  */
 interface ThemeHandlerInterface {
 
   /**
-   * Enables a given list of themes.
+   * Installs a given list of themes.
    *
    * @param array $theme_list
    *   An array of theme names.
-   * @param bool $enable_dependencies
+   * @param bool $install_dependencies
    *   (optional) If TRUE, dependencies will automatically be installed in the
    *   correct order. This incurs a significant performance cost, so use FALSE
    *   if you know $theme_list is already complete and in the correct order.
    *
    * @return bool
-   *   Whether any of the given themes have been enabled.
+   *   Whether any of the given themes have been installed.
    *
    * @throws \Drupal\Core\Extension\ExtensionNameLengthException
    *   Thrown when the theme name is to long
    */
-  public function enable(array $theme_list, $enable_dependencies = TRUE);
+  public function install(array $theme_list, $install_dependencies = TRUE);
 
   /**
-   * Disables a given list of themes.
+   * Uninstalls a given list of themes.
+   *
+   * Uninstalling a theme removes all related configuration (like blocks) and
+   * invokes the 'themes_uninstalled' hook.
    *
    * @param array $theme_list
-   *   An array of theme names.
+   *   The themes to uninstall.
    *
-   * @return bool
-   *   Whether any of the given themes have been disabled.
+   * @throws \InvalidArgumentException
+   *   Thrown when you uninstall an not installed theme.
+   *
+   * @see hook_themes_uninstalled()
    */
-  public function disable(array $theme_list);
+  public function uninstall(array $theme_list);
 
   /**
-   * Returns a list of currently enabled themes.
+   * Returns a list of currently installed themes.
    *
    * @return \Drupal\Core\Extension\Extension[]
-   *   An associative array of the currently enabled themes. The keys are the
+   *   An associative array of the currently installed themes. The keys are the
    *   themes' machine names and the values are objects having the following
    *   properties:
    *   - filename: The filepath and name of the .info.yml file.
    *   - name: The machine name of the theme.
-   *   - status: 1 for enabled, 0 for disabled themes.
+   *   - status: 1 for installed, 0 for uninstalled themes.
    *   - info: The contents of the .info.yml file.
    *   - stylesheets: A two dimensional array, using the first key for the
    *     media attribute (e.g. 'all'), the second for the name of the file
@@ -83,7 +88,7 @@ public function disable(array $theme_list);
   public function listInfo();
 
   /**
-   * Refreshes the theme info data of currently enabled themes.
+   * Refreshes the theme info data of currently installed themes.
    *
    * Modules can alter theme info, so this is typically called after a module
    * has been installed or uninstalled.
@@ -140,7 +145,17 @@ public function getName($theme);
   public function getDefault();
 
   /**
-   * Returns an array of directories for all enabled themes.
+   * Sets a new default theme.
+   *
+   * @param string $theme
+   *   The new default theme.
+   *
+   * @return $this
+   */
+  public function setDefault($theme);
+
+  /**
+   * Returns an array of directories for all installed themes.
    *
    * Useful for tasks such as finding a file that exists in all theme
    * directories.
@@ -150,13 +165,13 @@ public function getDefault();
   public function getThemeDirectories();
 
   /**
-   * Determines whether a given theme is enabled.
+   * Determines whether a given theme is installed.
    *
    * @param string $theme
    *   The name of the theme (without the .theme extension).
    *
    * @return bool
-   *   TRUE if the theme is both installed and enabled.
+   *   TRUE if the theme is installed.
    */
   public function themeExists($theme);
 

core/lib/Drupal/Core/Theme/ThemeAccessCheck.php

@@ -30,13 +30,13 @@ public function access($theme) {
   }
 
   /**
-   * Indicates whether the theme is accessible based on whether it is enabled.
+   * Indicates whether the theme is accessible based on whether it is installed.
    *
    * @param string $theme
    *   The name of a theme.
    *
    * @return bool
-   *   TRUE if the theme is enabled, FALSE otherwise.
+   *   TRUE if the theme is installed, FALSE otherwise.
    */
   public function checkAccess($theme) {
     $themes = list_themes();

core/lib/Drupal/Core/Theme/ThemeInitialization.php

@@ -64,15 +64,15 @@ public function getActiveThemeByName($theme_name) {
     $themes = $this->themeHandler->listInfo();
 
     // If no theme could be negotiated, or if the negotiated theme is not within
-    // the list of enabled themes, fall back to the default theme output of core
-    // and modules (like Stark, but without a theme extension at all). This is
-    // possible, because loadActiveTheme() always loads the Twig theme engine.
-    // This is desired, because missing or malformed theme configuration should
-    // not leave the application in a broken state. By falling back to default
-    // output, the user is able to reconfigure the theme through the UI.
+    // the list of installed themes, fall back to the default theme output of
+    // core and modules (like Stark, but without a theme extension at all). This
+    // is possible, because loadActiveTheme() always loads the Twig theme
+    // engine. This is desired, because missing or malformed theme configuration
+    // should not leave the application in a broken state. By falling back to
+    // default output, the user is able to reconfigure the theme through the UI.
     // Lastly, tests are expected to operate with no theme by default, so as to
     // only assert the original theme output of modules (unless a test manually
-    // enables a specific theme).
+    // installs a specific theme).
     if (empty($themes) || !$theme_name || !isset($themes[$theme_name])) {
       $theme_name = 'core';
       // /core/core.info.yml does not actually exist, but is required because

core/lib/Drupal/Core/Updater/Theme.php

@@ -82,7 +82,7 @@ public function postInstall() {
    */
   public function postInstallTasks() {
     return array(
-      l(t('Enable newly added themes'), 'admin/appearance'),
+      l(t('Install newly added themes'), 'admin/appearance'),
       l(t('Administration pages'), 'admin'),
     );
   }

core/lib/Drupal/Core/Utility/ProjectInfo.php

@@ -19,6 +19,10 @@ class ProjectInfo {
   /**
    * Populates an array of project data.
    *
+   * @todo https://www.drupal.org/node/2338167 update class since extensions can
+   *   no longer be hidden, enabled or disabled. Additionally, base themes have
+   *   to be installed for sub themes to work.
+   *
    * This iterates over a list of the installed modules or themes and groups
    * them by project and status. A few parts of this function assume that
    * enabled modules and themes are always processed first, and if disabled
@@ -51,15 +55,15 @@ function processInfoList(array &$projects, array $list, $project_type, $status,
       // projects list.
       if ($status && !empty($file->sub_themes)) {
         foreach ($file->sub_themes as $key => $name) {
-          // Build a list of enabled sub-themes.
+          // Build a list of installed sub-themes.
           if ($list[$key]->status) {
-            $file->enabled_sub_themes[$key] = $name;
+            $file->installed_sub_themes[$key] = $name;
           }
         }
-        // If the theme is disabled and there are no enabled subthemes, we
-        // should ignore this base theme for the enabled case. If the site is
-        // trying to display disabled themes, we'll catch it then.
-        if (!$file->status && empty($file->enabled_sub_themes)) {
+        // If the theme is uninstalled and there are no installed subthemes, we
+        // should ignore this base theme for the installed case. If the site is
+        // trying to display uninstalled themes, we'll catch it then.
+        if (!$file->status && empty($file->installed_sub_themes)) {
           continue;
         }
       }
@@ -73,8 +77,9 @@ function processInfoList(array &$projects, array $list, $project_type, $status,
         continue;
       }
 
-      // Skip if it's a hidden module or hidden theme without enabled sub-themes.
-      if (!empty($file->info['hidden']) && empty($file->enabled_sub_themes)) {
+      // Skip if it's a hidden module or hidden theme without installed
+      // sub-themes.
+      if (!empty($file->info['hidden']) && empty($file->installed_sub_themes)) {
         continue;
       }
 
@@ -115,10 +120,10 @@ function processInfoList(array &$projects, array $list, $project_type, $status,
       else {
         $project_display_type = $project_type;
       }
-      if (empty($status) && empty($file->enabled_sub_themes)) {
+      if (empty($status) && empty($file->installed_sub_themes)) {
         // If we're processing disabled modules or themes, append a suffix.
-        // However, we don't do this to a a base theme with enabled
-        // subthemes, since we treat that case as if it is enabled.
+        // However, we don't do this to a base theme with installed
+        // subthemes, since we treat that case as if it is installed.
         $project_display_type .= '-disabled';
       }
       // Add a list of sub-themes that "depend on" the project and a list of base
@@ -129,8 +134,8 @@ function processInfoList(array &$projects, array $list, $project_type, $status,
         $base_themes = array();
       }
       else {
-        // Add list of enabled sub-themes.
-        $sub_themes = !empty($file->enabled_sub_themes) ? $file->enabled_sub_themes : array();
+        // Add list of installed sub-themes.
+        $sub_themes = !empty($file->installed_sub_themes) ? $file->installed_sub_themes : array();
         // Add list of base themes.
         $base_themes = !empty($file->base_themes) ? $file->base_themes : array();
       }

core/modules/block/block.module

@@ -27,7 +27,7 @@ function block_help($route_name, RouteMatchInterface $route_match) {
       $output .= '<dt>' . t('Demonstrating block regions for a theme') . '</dt>';
       $output .= '<dd>' . t('You can see which region is where in a theme by clicking an the <em>Demonstrate block regions</em> link on the <a href="!blocks">Block layout page</a>. Regions are specific to each theme, so you need to toggle to a different theme first to demonstrate its block regions.', array('!blocks' => \Drupal::url('block.admin_display'))) . '</dd>';
       $output .= '<dt>' . t('Toggling between different themes') . '</dt>';
-      $output .= '<dd>' . t('Blocks are placed and configured specifically for each theme. The Block layout page opens with the default theme, but you can toggle to other enabled themes.') . '</dd>';
+      $output .= '<dd>' . t('Blocks are placed and configured specifically for each theme. The Block layout page opens with the default theme, but you can toggle to other installed themes.') . '</dd>';
       $output .= '<dt>' . t('Configuring block settings') . '</dt>';
       $output .= '<dd>' . t('To change the settings of an individual block click on the <em>Configure</em> link on the <a href="!blocks">Block layout page</a>. The available options vary depending on the module that provides the block. For all blocks you can change the block title and toggle whether to display it.', array('!blocks' => Drupal::url('block.admin_display'))) . '</dd>';
       $output .= '<dt>' . t('Controlling visibility') . '</dt>';
@@ -139,12 +139,12 @@ function _block_rehash($theme = NULL) {
 }
 
 /**
- * Initializes blocks for enabled themes.
+ * Initializes blocks for installed themes.
  *
  * @param $theme_list
  *   An array of theme names.
  */
-function block_themes_enabled($theme_list) {
+function block_themes_installed($theme_list) {
   foreach ($theme_list as $theme) {
     block_theme_initialize($theme);
   }
@@ -153,9 +153,9 @@ function block_themes_enabled($theme_list) {
 /**
  * Assigns an initial, default set of blocks for a theme.
  *
- * This function is called the first time a new theme is enabled. The new theme
- * gets a copy of the default theme's blocks, with the difference that if a
- * particular region isn't available in the new theme, the block is assigned
+ * This function is called the first time a new theme is installed. The new
+ * theme gets a copy of the default theme's blocks, with the difference that if
+ * a particular region isn't available in the new theme, the block is assigned
  * to the new theme's default region.
  *
  * @param $theme

core/modules/block/src/Tests/BlockAdminThemeTest.php

@@ -31,12 +31,13 @@ function testAdminTheme() {
     $admin_user = $this->drupalCreateUser(array('administer blocks', 'administer themes'));
     $this->drupalLogin($admin_user);
 
-    // Ensure that access to block admin page is denied when theme is disabled.
+    // Ensure that access to block admin page is denied when theme is not
+    // installed.
     $this->drupalGet('admin/structure/block/list/bartik');
     $this->assertResponse(403);
 
-    // Enable admin theme and confirm that tab is accessible.
-    theme_enable(array('bartik'));
+    // Install admin theme and confirm that tab is accessible.
+    \Drupal::service('theme_handler')->install(array('bartik'));
     $edit['admin_theme'] = 'bartik';
     $this->drupalPostForm('admin/appearance', $edit, t('Save configuration'));
     $this->drupalGet('admin/structure/block/list/bartik');

core/modules/block/src/Tests/BlockHiddenRegionTest.php

@@ -10,7 +10,7 @@
 use Drupal\simpletest\WebTestBase;
 
 /**
- * Tests that a newly enabled theme does not inherit blocks to its hidden
+ * Tests that a newly installed theme does not inherit blocks to its hidden
  * regions.
  *
  * @group block
@@ -45,7 +45,7 @@ protected function setUp() {
   }
 
   /**
-   * Tests that hidden regions do not inherit blocks when a theme is enabled.
+   * Tests that hidden regions do not inherit blocks when a theme is installed.
    */
   public function testBlockNotInHiddenRegion() {
 
@@ -53,13 +53,13 @@ public function testBlockNotInHiddenRegion() {
     $this->drupalGet('');
     $this->assertText('Search', 'Block was displayed on the front page.');
 
-    // Enable "block_test_theme" and set it as the default theme.
+    // Install "block_test_theme" and set it as the default theme.
     $theme = 'block_test_theme';
-    theme_enable(array($theme));
+    \Drupal::service('theme_handler')->install(array($theme));
     \Drupal::config('system.theme')
       ->set('default', $theme)
       ->save();
-    // Enabling a theme will cause the kernel terminate event to rebuild the
+    // Installing a theme will cause the kernel terminate event to rebuild the
     // router. Simulate that here.
     \Drupal::service('router.builder')->rebuildIfNeeded();
 

core/modules/block/src/Tests/BlockTest.php

@@ -154,8 +154,8 @@ function testBlock() {
    * Tests that the block form has a theme selector when not passed via the URL.
    */
   public function testBlockThemeSelector() {
-    // Enable all themes.
-    theme_enable(array('bartik', 'seven'));
+    // Install all themes.
+    \Drupal::service('theme_handler')->install(array('bartik', 'seven'));
     $theme_settings = $this->container->get('config.factory')->get('system.theme');
     foreach (array('bartik', 'stark', 'seven') as $theme) {
       $this->drupalGet('admin/structure/block/list/' . $theme);
@@ -185,7 +185,7 @@ function testThemeName() {
     $this->drupalPlaceBlock('system_help_block', array('region' => 'help'));
     // Explicitly set the default and admin themes.
     $theme = 'block_test_specialchars_theme';
-    theme_enable(array($theme));
+    \Drupal::service('theme_handler')->install(array($theme));
     \Drupal::service('router.builder')->rebuild();
     $this->drupalGet('admin/structure/block');
     $this->assertRaw(String::checkPlain('<"Cat" & \'Mouse\'>'));
@@ -377,4 +377,24 @@ public function testBlockCacheTags() {
     $this->assertEqual($this->drupalGetHeader('X-Drupal-Cache'), 'MISS');
   }
 
+  /**
+   * Tests that uninstalling a theme removes its block configuration.
+   */
+  public function testUninstallTheme() {
+    /** @var \Drupal\Core\Extension\ThemeHandlerInterface $theme_handler */
+    $theme_handler = \Drupal::service('theme_handler');
+
+    $theme_handler->install(['seven']);
+    $theme_handler->setDefault('seven');
+    $block = $this->drupalPlaceBlock('system_powered_by_block', ['theme' => 'seven', 'region' => 'help']);
+    $this->drupalGet('<front>');
+    $this->assertText('Powered by Drupal');
+
+    $theme_handler->setDefault('stark');
+    $theme_handler->uninstall(['seven']);
+
+    // Ensure that the block configuration does not exist anymore.
+    $this->assertIdentical(NULL, Block::load($block->id()));
+  }
+
 }

core/modules/block/src/Tests/NewDefaultThemeBlocksTest.php

@@ -42,10 +42,10 @@ function testNewDefaultThemeBlocks() {
       'id' => $default_theme . '_' . strtolower($this->randomMachineName(8)),
     ));
 
-    // Enable a different theme.
+    // Install a different theme.
     $new_theme = 'bartik';
     $this->assertFalse($new_theme == $default_theme, 'The new theme is different from the previous default theme.');
-    theme_enable(array($new_theme));
+    \Drupal::service('theme_handler')->install(array($new_theme));
     \Drupal::config('system.theme')
       ->set('default', $new_theme)
       ->save();

core/modules/block/src/Tests/NonDefaultBlockAdminTest.php

@@ -30,7 +30,7 @@ function testNonDefaultBlockAdmin() {
     $admin_user = $this->drupalCreateUser(array('administer blocks', 'administer themes'));
     $this->drupalLogin($admin_user);
     $new_theme = 'bartik';
-    theme_enable(array($new_theme));
+    \Drupal::service('theme_handler')->install(array($new_theme));
     $this->drupalGet('admin/structure/block/list/' . $new_theme);
     $this->assertText('Bartik(' . t('active tab') . ')', 'Tab for non-default theme found.');
   }

core/modules/block_content/src/Tests/BlockContentTypeTest.php

@@ -142,8 +142,8 @@ public function testsBlockContentAddTypes() {
       ->get('entity.manager')
       ->getStorage('block_content');
 
-    // Enable all themes.
-    theme_enable(array('bartik', 'seven'));
+    // Install all themes.
+    \Drupal::service('theme_handler')->install(array('bartik', 'seven'));
     $themes = array('bartik', 'seven', 'stark');