直接在 Factory 中设计 user_id 的填充，我觉得更容易理解一些？

StatusFactory.php

<?php

use Faker\Generator as Faker;

$factory->define(App\Models\Status::class, function (Faker $faker) {
    $date_time = $faker->date . ' ' . $faker->time;
    return [
        'content' => $faker->text(),
        'created_at' => $date_time,
        'updated_at' => $date_time,
        'user_id' => $faker->randomElement([1,2,3]),
    ];
});

StatusesTableSeeder.php

<?php

use Illuminate\Database\Seeder;
use App\Models\User;
use App\Models\Status;

class StatusesTableSeeder extends Seeder
{
    /**
     * Run the database seeds.
     *
     * @return void
     */
    public function run()
    {
       $statuses = factory(Status::class)->times(100)->make();
       Status::insert($statuses->toArray());
    }
}