Install composer phpunit v9 for development testing

vendor/nikic/php-parser/lib/PhpParser/Builder.php

@@ -0,0 +1,13 @@
+<?php declare(strict_types=1);
+
+namespace PhpParser;
+
+interface Builder
+{
+    /**
+     * Returns the built node.
+     *
+     * @return Node The built node
+     */
+    public function getNode() : Node;
+}