OverwriteExistingPackagesValidator.php

<?php

declare (strict_types=1);
namespace Drupal\package_manager\Validator;

use Drupal\Core\StringTranslation\StringTranslationTrait;
use Drupal\package_manager\ComposerInspector;
use Drupal\package_manager\Event\PreApplyEvent;
use Drupal\package_manager\PathLocator;
use Symfony\Component\EventDispatcher\EventSubscriberInterface;

/**
 * Validates that newly installed packages don't overwrite existing directories.
 *
 * Whether a new package in the stage directory would overwrite an existing
 * directory in the active directory when the operation is applied is determined
 * by inspecting the `path` property of the staged package.
 *
 * Certain packages, such as those with the `metapackage` type, don't have a
 * `path` property and are ignored by this validator. The Composer facade at
 * https://packages.drupal.org/8 currently uses the `metapackage` type for
 * submodules of Drupal projects.
 *
 * @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
 *   class.
 *
 * @see https://getcomposer.org/doc/04-schema.md#type
 */
final class OverwriteExistingPackagesValidator implements EventSubscriberInterface {
    use StringTranslationTrait;
    public function __construct(PathLocator $pathLocator, ComposerInspector $composerInspector) {
    }
    
    /**
     * Validates that new installed packages don't overwrite existing directories.
     *
     * @param \Drupal\package_manager\Event\PreApplyEvent $event
     *   The event being handled.
     */
    public function validate(PreApplyEvent $event) : void {
        $active_dir = $this->pathLocator
            ->getProjectRoot();
        $stage_dir = $event->stage
            ->getStageDirectory();
        $active_packages = $this->composerInspector
            ->getInstalledPackagesList($active_dir);
        $new_packages = $this->composerInspector
            ->getInstalledPackagesList($stage_dir)
            ->getPackagesNotIn($active_packages);
        foreach ($new_packages as $package) {
            if (empty($package->path)) {
                // Packages without a `path` cannot overwrite existing directories.
                continue;
            }
            $relative_path = str_replace($stage_dir, '', $package->path);
            if (is_dir($active_dir . DIRECTORY_SEPARATOR . $relative_path)) {
                $event->addError([
                    $this->t('The new package @package will be installed in the directory @path, which already exists but is not managed by Composer.', [
                        '@package' => $package->name,
                        '@path' => $relative_path,
                    ]),
                ]);
            }
        }
    }
    
    /**
     * {@inheritdoc}
     */
    public static function getSubscribedEvents() : array {
        return [
            PreApplyEvent::class => 'validate',
        ];
    }

}