EntityCollection.php

См. документацию.

<?php
 
declare(strict_types=1);
 
namespace Bitrix\Main\Entity;
 
use Bitrix\Main\ArgumentTypeException;
 
class EntityCollection implements EntityCollectionInterface
{
    protected array $items = [];
 
    public function __construct(EntityInterface ...$items)
    {
        foreach ($items as $item)
        {
            $this->add($item);
        }
    }
 
    public function count(): int
    {
        return count($this->items);
    }
 
    public function isEmpty(): bool
    {
        return empty($this->items);
    }
 
    public function getIterator(): \ArrayIterator
    {
        return new \ArrayIterator($this->items);
    }

    public function add(EntityInterface $item): void
    {
        if (!is_a($item, static::getEntityClass()))
        {
            throw new ArgumentTypeException('item', static::getEntityClass());
        }
 
        $this->items[] = $item;
    }
 
    public function find(callable $callback): ?EntityInterface
    {
        // On PHP 8.4 replace to
        // return array_find($this->items, $callback);
 
        foreach ($this->items as $key => $item)
        {
            if ($callback($item, $key))
            {
                return $item;
            }
        }
 
        return null;
    }
 
    public function filter(callable $callback): static
    {
        return new static(...array_filter($this->items, $callback));
    }

    public function map(callable $callback): array
    {
        return array_map($callback, $this->items);
    }

    protected static function getEntityClass(): string
    {
        return EntityInterface::class;
    }
}