Resolve #3408488 "Make unknownpathexcluder accept"

Closes #3408488

package_manager/src/PathExcluder/UnknownPathExcluder.php

@@ -24,6 +24,12 @@ use Symfony\Component\EventDispatcher\EventSubscriberInterface;
  *
  * If web root and project root are the same, nothing is excluded.
  *
+ * This excluder can be bypassed by changing the config setting
+ * `package_manager.settings:include_unknown_files` to TRUE. This may be needed
+ * for sites that have files outside the web root which are nonetheless needed
+ * in order for Composer to assemble the code base correctly; a classic example
+ * would be a directory of patch files used by `cweagans/composer-patches`.
+ *
  * @internal
  *   This is an internal part of Package Manager and may be changed or removed
  *   at any time without warning. External code should not interact with this
@@ -70,57 +76,65 @@ final class UnknownPathExcluder implements EventSubscriberInterface {
       return;
     }
 
-    $project_root = $this->pathLocator->getProjectRoot();
-    $web_root = $project_root . DIRECTORY_SEPARATOR . $this->pathLocator->getWebRoot();
-    if (realpath($web_root) === $project_root) {
+    // If the project root and web root are the same, there's nothing to do.
+    $web_root = $this->pathLocator->getWebRoot();
+    if (empty($web_root)) {
       return;
     }
 
-    // To determine the scaffold files to exclude, the installed packages must
-    // be known, and that requires Composer commands to be able to run. This
-    // intentionally does not catch exceptions: failed Composer validation in
-    // the project root implies that this excluder cannot function correctly.
-    // Note: the call to ComposerInspector::getInstalledPackagesList() would
+    // To determine the files to include, the installed packages must be known,
+    // and that requires Composer commands to be able to run. This intentionally
+    // does not catch exceptions: failed Composer validation in the project root
+    // implies that this excluder cannot function correctly.
+    // Note: the call to ComposerInspector::getConfig() would
     // also have triggered this, but explicitness is preferred here.
     // @see \Drupal\package_manager\StatusCheckTrait::runStatusCheck()
+    $project_root = $this->pathLocator->getProjectRoot();
     $this->composerInspector->validate($project_root);
 
-    $vendor_dir = $this->pathLocator->getVendorDirectory();
-    $scaffold_files_paths = $this->getScaffoldFiles();
+    // The vendor directory and web root are always included in staging
+    // operations, along with `composer.json`, `composer.lock`, and any scaffold
+    // files provided by Drupal core.
+    $always_include = [
+      $this->composerInspector->getConfig('vendor-dir', $project_root),
+      $web_root,
+      'composer.json',
+      'composer.lock',
+    ];
+    foreach ($this->getScaffoldFiles() as $scaffold_file_path) {
+      // The web root is always included in staging operations, so we don't need
+      // to do anything special for scaffold files that live in it.
+      if (str_starts_with($scaffold_file_path, '[web-root]')) {
+        continue;
+      }
+      $always_include[] = ltrim($scaffold_file_path, '/');
+    }
 
     // Search for all files (including hidden ones) in the project root. We need
     // to use readdir() and friends here, rather than glob(), since certain
     // glob() flags aren't supported on all systems. We also can't use
     // \Drupal\Core\File\FileSystemInterface::scanDirectory(), because it
     // unconditionally ignores hidden files and directories.
-    $paths_in_project_root = [];
     $handle = opendir($project_root);
     if (empty($handle)) {
       throw new \RuntimeException("Could not scan for files in the project root.");
     }
-    while (($entry = readdir($handle)) !== FALSE) {
-      if ($entry === '.' || $entry === '..') {
+    while ($entry = readdir($handle)) {
+      if ($entry === '.' || $entry === '..' || in_array($entry, $always_include, TRUE)) {
         continue;
       }
-      $paths_in_project_root[] = $project_root . DIRECTORY_SEPARATOR . $entry;
+      // We can add the path as-is; it's already relative to the project root.
+      $event->add($entry);
     }
     closedir($handle);
-
-    $paths = [];
-    $known_paths = array_merge([$vendor_dir, $web_root, "$project_root/composer.json", "$project_root/composer.lock"], $scaffold_files_paths);
-    foreach ($paths_in_project_root as $path_in_project_root) {
-      if (!in_array($path_in_project_root, $known_paths, TRUE)) {
-        $paths[] = $path_in_project_root;
-      }
-    }
-    $event->addPathsRelativeToProjectRoot($paths);
   }
 
   /**
    * Gets the path of scaffold files, for example 'index.php' and 'robots.txt'.
    *
-   * @return array
-   *   The array of scaffold file paths.
+   * @return string[]
+   *   The paths of scaffold files provided by `drupal/core`, relative to the
+   *   project root.
    *
    * @todo Intelligently load scaffold files in https://drupal.org/i/3343802.
    */
@@ -128,10 +142,9 @@ final class UnknownPathExcluder implements EventSubscriberInterface {
     $project_root = $this->pathLocator->getProjectRoot();
     $packages = $this->composerInspector->getInstalledPackagesList($project_root);
     $extra = Json::decode($this->composerInspector->getConfig('extra', $packages['drupal/core']->path . '/composer.json'));
-    if (isset($extra['drupal-scaffold']['file-mapping'])) {
-      return array_keys($extra['drupal-scaffold']['file-mapping']);
-    }
-    return [];
+
+    $scaffold_files = array_keys($extra['drupal-scaffold']['file-mapping'] ?? []);
+    return str_replace('[project-root]', '', $scaffold_files);
   }
 
 }