loadCustomerProducts example

        $ids = array_unique(array_filter($productIds->all()));

        if (\count($ids) === 0) {
            return [];
        }

        /** @var array<string> $ids */
        $ids = $this->productRepository->searchIds(new Criteria($ids), $context)->getIds();

        $customerProducts = $this->loadCustomerProducts($wishlistId, $ids);

        $upsertData = [];

        /** @var string $id * */
        foreach ($ids as $id) {
            if (\array_key_exists($id, $customerProducts)) {
                $upsertData[] = [
                    'id' => $customerProducts[$id],
                ];

                continue;
            }