Хочу выиграть билет от канала Пых на PHPFest 2020

ReportFactory.php

<?php

final class Data
{
    // ...
}

final class Report
{
    // ...
}

interface ReportFactory
{
    public function createReport(Data $data): Report;
}

/**
 * Registered as a shared DI service
 */
final class HeavyReportFactory implements ReportFactory
{
    public function createReport(Data $data): Report
    {
        // ...

        return new Report();
    }
}

/**
 * Registered as a shared DI service
 */
final class InMemoryCachingReportFactory implements ReportFactory
{
    private ReportFactory $reportFactory;

    /**
     * @var SplObjectStorage<Data, Report>
     */
    private SplObjectStorage $reports;

    public function __construct(ReportFactory $reportFactory)
    {
        $this->reportFactory = $reportFactory;
        $this->reports = new SplObjectStorage();
    }

    public function createReport(Data $data): Report
    {
        return $this->reports[$data] ??= $this->reportFactory->createReport($data);
    }
}