Issue #3376399: Override new lazy asset collection optimizers

src/Asset/CssCollectionOptimizerLazy.php

+<?php
+
+namespace Drupal\flysystem\Asset;
+
+use Drupal\Core\Asset\CssCollectionOptimizerLazy as DrupalCssCollectionOptimizerLazy;
+use Drupal\Core\File\Exception\FileException;
+
+/**
+ * Optimizes CSS assets.
+ */
+class CssCollectionOptimizerLazy extends DrupalCssCollectionOptimizerLazy {
+
+  use SchemeExtensionTrait;
+
+  /**
+   * {@inheritdoc}
+   */
+  public function deleteAll() {
+    $this->state->delete('drupal_css_cache_files');
+    try {
+      $this->fileSystem->deleteRecursive($this->getSchemeForExtension('css') . '://css');
+    } catch (FileException $fileException) {
+      \Drupal::logger('flysystem')->error($fileException->getMessage());
+    }
+  }
+
+}

src/Asset/JsCollectionOptimizerLazy.php

+<?php
+
+namespace Drupal\flysystem\Asset;
+
+use Drupal\Core\Asset\JsCollectionOptimizerLazy as DrupalJsCollectionOptimizerLazy;
+use Drupal\Core\File\Exception\FileException;
+
+/**
+ * Optimizes JavaScript assets.
+ */
+class JsCollectionOptimizerLazy extends DrupalJsCollectionOptimizerLazy {
+
+  use SchemeExtensionTrait;
+
+  /**
+   * {@inheritdoc}
+   */
+  public function deleteAll() {
+    $this->state->delete('system.js_cache_files');
+    try {
+      $this->fileSystem->deleteRecursive($this->getSchemeForExtension('js') . '://js');
+    } catch (FileException $fileException) {
+      \Drupal::logger('flysystem')->error($fileException->getMessage());
+    }
+  }
+
+}

src/Asset/SchemeExtensionTrait.php

@@ -3,6 +3,7 @@
 namespace Drupal\flysystem\Asset;
 
 use Drupal\Core\Site\Settings;
+use Drupal\Core\StreamWrapper\AssetsStream;
 
 /**
  * Flysystem dependency injection container.
@@ -19,11 +20,14 @@ trait SchemeExtensionTrait {
    *   The scheme that should serve the extension.
    */
   public function getSchemeForExtension($extension) {
-
+    $has_assets_scheme = class_exists(AssetsStream::class);
     $extension_scheme = 'public';
 
     foreach (Settings::get('flysystem', []) as $scheme => $configuration) {
       if (!empty($configuration['serve_' . $extension]) && !empty($configuration['driver'])) {
+        if ($has_assets_scheme) {
+          @trigger_error(sprintf('The serve_%s Flysystem option is deprecated in flysystem:2.1.0 and is removed from flysystem:3.0.0. Use the assets:// stream wrapper instead. See https://www.drupal.org/node/3328126', $extension), E_USER_DEPRECATED);
+        }
         // Don't break, the last configured one will win.
         $extension_scheme = $scheme;
       }

src/FlysystemServiceProvider.php

@@ -68,9 +68,14 @@ class FlysystemServiceProvider implements ServiceProviderInterface {
     $container
       ->getDefinition('asset.' . $extension . '.dumper')
       ->setClass('Drupal\flysystem\Asset\AssetDumper');
-    $container
-      ->getDefinition('asset.' . $extension . '.collection_optimizer')
-      ->setClass('Drupal\flysystem\Asset\\' . ucfirst($extension) . 'CollectionOptimizer');
+
+    $optimizer = $container->getDefinition('asset.' . $extension . '.collection_optimizer');
+    if ($optimizer->getClass() === 'Drupal\Core\Asset\\' . ucfirst($extension) . 'CollectionOptimizer') {
+      $optimizer->setClass('Drupal\flysystem\Asset\\' . ucfirst($extension) . 'CollectionOptimizer');
+    }
+    if ($optimizer->getClass() === 'Drupal\Core\Asset\\' . ucfirst($extension) . 'CollectionOptimizerLazy') {
+      $optimizer->setClass('Drupal\flysystem\Asset\\' . ucfirst($extension) . 'CollectionOptimizerLazy');
+    }
 
     if ($extension === 'css') {
       $container

src/PathProcessor/LocalPathProcessor.php

@@ -50,6 +50,10 @@ class LocalPathProcessor implements InboundPathProcessorInterface {
 
     $rest = substr($path, strlen($this->root) + 2);
 
+    if (preg_match('#^(js|css)/#', $rest)) {
+      return $path;
+    }
+
     if (strpos($rest, 'styles/') === 0 && substr_count($rest, '/') >= 3) {
       [, $image_style, $scheme, $file] = explode('/', $rest, 4);