screen/application/common/service/CouponService.php

<?php
namespace app\common\service;

use app\common\model\GoodsSku;
use app\common\model\UserCoupon;
use traits\think\Instance;

class CouponService{
    use Instance;
    /** @var UserCoupon */
    protected $coupon;
    protected $sku;

    /**
     * @param UserCoupon $coupon
     */
    public function setCoupon(UserCoupon $coupon)
    {
        $this->coupon = $coupon;
        return $this;
    }

    /**
     */
    public function setSku($sku)
    {
        $this->sku = $sku;
        return $this;
    }

    public function check(){
    }
}