GraphQL\Validator\Rules\KnownTypeNames::__invoke PHP Method

    public function __invoke(ValidationContext $context)
    {
        $skip = function () {
            return Visitor::skipNode();
        };
        return [NodeKind::OBJECT_TYPE_DEFINITION => $skip, NodeKind::INTERFACE_TYPE_DEFINITION => $skip, NodeKind::UNION_TYPE_DEFINITION => $skip, NodeKind::INPUT_OBJECT_TYPE_DEFINITION => $skip, NodeKind::NAMED_TYPE => function (NamedTypeNode $node, $key) use($context) {
            $typeName = $node->name->value;
            $type = $context->getSchema()->getType($typeName);
            if (!$type) {
                $context->reportError(new Error(self::unknownTypeMessage($typeName), [$node]));
            }
        }];
    }