GraphQL\Validator\ValidationContext::getRecursivelyReferencedFragments PHP Метод

    function getRecursivelyReferencedFragments(OperationDefinitionNode $operation)
    {
        $fragments = isset($this->recursivelyReferencedFragments[$operation]) ? $this->recursivelyReferencedFragments[$operation] : null;
        if (!$fragments) {
            $fragments = [];
            $collectedNames = [];
            $nodesToVisit = [$operation];
            while (!empty($nodesToVisit)) {
                $node = array_pop($nodesToVisit);
                $spreads = $this->getFragmentSpreads($node);
                for ($i = 0; $i < count($spreads); $i++) {
                    $fragName = $spreads[$i]->name->value;
                    if (empty($collectedNames[$fragName])) {
                        $collectedNames[$fragName] = true;
                        $fragment = $this->getFragment($fragName);
                        if ($fragment) {
                            $fragments[] = $fragment;
                            $nodesToVisit[] = $fragment;
                        }
                    }
                }
            }
            $this->recursivelyReferencedFragments[$operation] = $fragments;
        }
        return $fragments;
    }

 public function __invoke(ValidationContext $context)
 {
     $this->operationDefs = [];
     $this->fragmentDefs = [];
     return [NodeKind::OPERATION_DEFINITION => function ($node) {
         $this->operationDefs[] = $node;
         return Visitor::skipNode();
     }, NodeKind::FRAGMENT_DEFINITION => function (FragmentDefinitionNode $def) {
         $this->fragmentDefs[] = $def;
         return Visitor::skipNode();
     }, NodeKind::DOCUMENT => ['leave' => function () use($context) {
         $fragmentNameUsed = [];
         foreach ($this->operationDefs as $operation) {
             foreach ($context->getRecursivelyReferencedFragments($operation) as $fragment) {
                 $fragmentNameUsed[$fragment->name->value] = true;
             }
         }
         foreach ($this->fragmentDefs as $fragmentDef) {
             $fragName = $fragmentDef->name->value;
             if (empty($fragmentNameUsed[$fragName])) {
                 $context->reportError(new Error(self::unusedFragMessage($fragName), [$fragmentDef]));
             }
         }
     }]];
 }