Issue #3363938: Package Manager should ignore default.settings.php and default.services.yml

package_manager/src/PathExcluder/SiteConfigurationExcluder.php

@@ -87,13 +87,16 @@ class SiteConfigurationExcluder implements EventSubscriberInterface {
    *
    * @throws \Drupal\Core\File\Exception\FileException
    *   If the permissions of the either the live or staged `sites/default`
-   *   cannot be determined, or changed on the staged `sites/default`.
+   *   cannot be determined, or cannot be changed on the staged `sites/default`.
    */
   public function syncDefaultSiteDirectoryPermissions(PreApplyEvent $event): void {
     $live_dir = $this->getDefaultSiteDirectoryPath($this->pathLocator->getProjectRoot());
     $staged_dir = $this->getDefaultSiteDirectoryPath($event->stage->getStageDirectory());
 
-    // This is borrowed from \Symfony\Component\Filesystem\Filesystem::copy().
+    // This is borrowed from \Symfony\Component\Filesystem\Filesystem::copy(),
+    // to ensure the correct permissions are preserved (chmod() requires
+    // permissions to be sent as an octal number, but fileperms() returns a
+    // decimal number, because PHP is just great.
     $permissions = $this->getPermissions($staged_dir) | ($this->getPermissions($live_dir) & 0111);
 
     if (!$this->fileSystem->chmod($staged_dir, $permissions)) {