Chris@13: <?php declare(strict_types=1);
Chris@13: 
Chris@13: namespace PhpParser\NodeVisitor;
Chris@13: 
Chris@13: use PhpParser\Node;
Chris@13: use PhpParser\NodeVisitorAbstract;
Chris@13: 
Chris@13: /**
Chris@13:  * This visitor can be used to find and collect all nodes satisfying some criterion determined by
Chris@13:  * a filter callback.
Chris@13:  */
Chris@13: class FindingVisitor extends NodeVisitorAbstract
Chris@13: {
Chris@13:     /** @var callable Filter callback */
Chris@13:     protected $filterCallback;
Chris@13:     /** @var Node[] Found nodes */
Chris@13:     protected $foundNodes;
Chris@13: 
Chris@13:     public function __construct(callable $filterCallback) {
Chris@13:         $this->filterCallback = $filterCallback;
Chris@13:     }
Chris@13: 
Chris@13:     /**
Chris@13:      * Get found nodes satisfying the filter callback.
Chris@13:      *
Chris@13:      * Nodes are returned in pre-order.
Chris@13:      *
Chris@13:      * @return Node[] Found nodes
Chris@13:      */
Chris@13:     public function getFoundNodes() : array {
Chris@13:         return $this->foundNodes;
Chris@13:     }
Chris@13: 
Chris@13:     public function beforeTraverse(array $nodes) {
Chris@13:         $this->foundNodes = [];
Chris@13: 
Chris@13:         return null;
Chris@13:     }
Chris@13: 
Chris@13:     public function enterNode(Node $node) {
Chris@13:         $filterCallback = $this->filterCallback;
Chris@13:         if ($filterCallback($node)) {
Chris@13:             $this->foundNodes[] = $node;
Chris@13:         }
Chris@13: 
Chris@13:         return null;
Chris@13:     }
Chris@13: }