Update to Drupal 8.2.0. For more information, see https://www.drupal.org/project/drupal/releases/8.2.0

core/lib/Drupal/Core/Extension/Discovery/RecursiveExtensionFilterIterator.php

@@ -81,6 +81,20 @@ class RecursiveExtensionFilterIterator extends \RecursiveFilterIterator {
    */
   protected $acceptTests = FALSE;
 
+  /**
+   * Construct a RecursiveExtensionFilterIterator.
+   *
+   * @param \RecursiveIterator $iterator
+   *   The iterator to filter.
+   * @param array $blacklist
+   *   (optional) Add to the blacklist of directories that should be filtered
+   *   out during the iteration.
+   */
+  public function __construct(\RecursiveIterator $iterator, array $blacklist = []) {
+    parent::__construct($iterator);
+    $this->blacklist = array_merge($this->blacklist, $blacklist);
+  }
+
   /**
    * Controls whether test directories will be scanned.
    *
@@ -102,6 +116,8 @@ class RecursiveExtensionFilterIterator extends \RecursiveFilterIterator {
    */
   public function getChildren() {
     $filter = parent::getChildren();
+    // Pass on the blacklist.
+    $filter->blacklist = $this->blacklist;
     // Pass the $acceptTests flag forward to child iterators.
     $filter->acceptTests($this->acceptTests);
     return $filter;

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

@@ -427,11 +427,17 @@ class ExtensionDiscovery {
     $flags |= \FilesystemIterator::CURRENT_AS_SELF;
     $directory_iterator = new \RecursiveDirectoryIterator($absolute_dir, $flags);
 
+    // Allow directories specified in settings.php to be ignored. You can use
+    // this to not check for files in common special-purpose directories. For
+    // example, node_modules and bower_components. Ignoring irrelevant
+    // directories is a performance boost.
+    $ignore_directories = Settings::get('file_scan_ignore_directories', []);
+
     // Filter the recursive scan to discover extensions only.
     // Important: Without a RecursiveFilterIterator, RecursiveDirectoryIterator
     // would recurse into the entire filesystem directory tree without any kind
     // of limitations.
-    $filter = new RecursiveExtensionFilterIterator($directory_iterator);
+    $filter = new RecursiveExtensionFilterIterator($directory_iterator, $ignore_directories);
     $filter->acceptTests($include_tests);
 
     // The actual recursive filesystem scan is only invoked by instantiating the

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

@@ -2,8 +2,8 @@
 
 namespace Drupal\Core\Extension;
 
-use Drupal\Component\Serialization\Yaml;
 use Drupal\Component\Serialization\Exception\InvalidDataTypeException;
+use Drupal\Core\Serialization\Yaml;
 
 /**
  * Parses dynamic .info.yml files that might change during the page request.

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

@@ -581,8 +581,8 @@ class ModuleHandler implements ModuleHandlerInterface {
       $this->alter('module_implements', $implementations, $hook);
       // Verify new or modified implementations.
       foreach (array_diff_assoc($implementations, $implementations_before) as $module => $group) {
-        // If drupal_alter('module_implements') changed or added a $group, the
-        // respective file needs to be included.
+        // If an implementation of hook_module_implements_alter() changed or
+        // added a group, the respective file needs to be included.
         if ($group) {
           $this->loadInclude($module, 'inc', "$module.$group");
         }

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

@@ -2,12 +2,12 @@
 
 namespace Drupal\Core\Extension;
 
-use Drupal\Component\Serialization\Yaml;
 use Drupal\Core\Cache\Cache;
 use Drupal\Core\Cache\CacheBackendInterface;
 use Drupal\Core\DrupalKernelInterface;
 use Drupal\Core\Entity\EntityStorageException;
 use Drupal\Core\Entity\FieldableEntityInterface;
+use Drupal\Core\Serialization\Yaml;
 
 /**
  * Default implementation of the module installer.

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

@@ -198,8 +198,10 @@ class ThemeHandler implements ThemeHandlerInterface {
    * {@inheritdoc}
    */
   public function addTheme(Extension $theme) {
-    foreach ($theme->info['libraries'] as $library => $name) {
-      $theme->libraries[$library] = $name;
+    if (!empty($theme->info['libraries'])) {
+      foreach ($theme->info['libraries'] as $library => $name) {
+        $theme->libraries[$library] = $name;
+      }
     }
     if (isset($theme->info['engine'])) {
       $theme->engine = $theme->info['engine'];

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

@@ -223,7 +223,7 @@ class ThemeInstaller implements ThemeInstallerInterface {
         throw new \InvalidArgumentException("The current default theme $key cannot be uninstalled.");
       }
       if ($key === $theme_config->get('admin')) {
-        throw new \InvalidArgumentException("The current admin theme $key cannot be uninstalled.");
+        throw new \InvalidArgumentException("The current administration theme $key cannot be uninstalled.");
       }
       // Base themes cannot be uninstalled if sub themes are installed, and if
       // they are not uninstalled at the same time.