SATE-EasyReceipt/app/Models/Contract.php

<?php

namespace App\Models;

use Illuminate\Support\Str;

class Contract extends AppModel
{

    const COL_NAME_NAME = 'name';
    const COL_NAME_CUSTOM = 'custom';

    public function getModelName(): string
    {
        return "契約";
    }

    public function includeCustom(string $target): bool
    {
        return in_array($target, $this->custom(), true);
    }

    public function custom(): array
    {
        $custom = data_get($this, self::COL_NAME_CUSTOM);
        if ($custom) {
            return explode(',', $custom);
        } else {
            return [];
        }
    }
}