TYPO3 v15 dev-main snapshot ()

Classes/Upgrades/PrerequisiteCollection.php

@@ -0,0 +1,52 @@
+<?php
+
+declare(strict_types=1);
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+namespace TYPO3\CMS\Core\Upgrades;
+
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+
+/**
+ * Collection of prerequisites used internally in upgrade wizard commands.
+ *
+ * @internal for use in upgrade wizard command only and not part of public API.
+ */
+final class PrerequisiteCollection implements \IteratorAggregate
+{
+    private \ArrayObject $prerequisites;
+
+    public function __construct()
+    {
+        $this->prerequisites = new \ArrayObject();
+    }
+
+    public function add(string $prerequisiteClass): void
+    {
+        if (
+            !($this->prerequisites[$prerequisiteClass] ?? false)
+            && is_a($prerequisiteClass, PrerequisiteInterface::class, true)
+        ) {
+            $this->prerequisites[$prerequisiteClass] = GeneralUtility::makeInstance(
+                $prerequisiteClass
+            );
+        }
+    }
+
+    public function getIterator(): \Traversable
+    {
+        return $this->prerequisites;
+    }
+}