Transformer 对 item,array 为什么没反应呢？

    public function index(Request $request, Consult $consult)
    {
        return $this->response->collection($this->user()->consults, new ConsultTransformer());
    }

Transformer:

class ConsultTransformer extends TransformerAbstract
{
    public function transform(Consult $consult)
    {
        return [
            'id' => $consult->id,
            'username' => $consult->username,
        ];
    }
}

响应：
item:

{
    "status": "success",
    "code": "200",
    "data": {
        "mcar_consults": [
            {
                "id": 3,
                "username": "watts2",
                "mobile": "17682310000",
                "sales_id": null,
                "due_at": null,
                "shop_address": null,
                "delivery_type": "到店提车",
                "follow_status": "新咨询",
                "content": null,
                "product_id": 50,
                "order_id": null,
                "customer_id": 8,
                "count": 24,
                "status": 1,
                "created_at": "2018-11-26 12:22:50",
                "updated_at": "2018-11-26 12:22:50"
            },
            {
                "id": 4,
                "username": "watts3",
                "mobile": "17682310000",
                "sales_id": null,
                "due_at": null,
                "shop_address": null,
                "delivery_type": "到店提车",
                "follow_status": "新咨询",
                "content": null,
                "product_id": 50,
                "order_id": null,
                "customer_id": 8,
                "count": 24,
                "status": 1,
                "created_at": "2018-11-26 12:22:54",
                "updated_at": "2018-11-26 12:22:54"
            }
        ]
    }
}

array:

{
    "status": "success",
    "code": "200",
    "data": {
        "mcar_consults": [
            {
                "id": 3,
                "username": "watts2",
                "mobile": "17682310000",
                "sales_id": null,
                "due_at": null,
                "shop_address": null,
                "delivery_type": "到店提车",
                "follow_status": "新咨询",
                "content": null,
                "product_id": 50,
                "order_id": null,
                "customer_id": 8,
                "count": 24,
                "status": 1,
                "created_at": "2018-11-26 12:22:50",
                "updated_at": "2018-11-26 12:22:50"
            },
            {
                "id": 4,
                "username": "watts3",
                "mobile": "17682310000",
                "sales_id": null,
                "due_at": null,
                "shop_address": null,
                "delivery_type": "到店提车",
                "follow_status": "新咨询",
                "content": null,
                "product_id": 50,
                "order_id": null,
                "customer_id": 8,
                "count": 24,
                "status": 1,
                "created_at": "2018-11-26 12:22:54",
                "updated_at": "2018-11-26 12:22:54"
            }
        ]
    }
}

colleciton：

{
    "status": "success",
    "code": "200",
    "data": {
        "data": [
            {
                "id": 3,
                "username": "watts2"
            },
            {
                "id": 4,
                "username": "watts3"
            }
        ]
    }
}