错误：在Laravel中使用工厂时，“类Closure的对象无法转换为字符串”

I am trying to create some dummy data to testunit my appication in Laravel 5.7. I am using a factory to create:

• Profiles
• 5 Events that belongs to that profile
• 10 Eventcomments that belongs to each of the previous events.

All in one.

My factory looks like this:

$factory->define(App\Profile::class, function (Faker $faker) {

    $profile = Profile::create([
        'title'     => $faker->userName,
        'gender_id' => 0,
        'role_id'   => 1,
        'slug'      => str_slug($faker->userName),
    ]);

    for ($i=0; $i < 5; $i++) { 
        $event = Event::create([
            'profile_id'    => $profile->id,
            'title'         => $faker->sentence,
            'subtitle'      => $faker->sentence,
            'slug'          => str_slug($faker->sentence),      
            'category_id'   => 1,
            'language_id'   => 1,
            'video_url'     =>  'video',
            'description'   =>  $faker->paragraph,
        ]);

        for ($i=0; $i < 10; $i++) { 
            $eventcomment = Eventcomment::create([
                'profile_id'    => $profile->id,
                'event_id'      => $event->id,
                'body'          =>  $faker->paragraph,
            ]);
        }   
    }

    return $profile;
});

But when I run it in Tinker like this:

php artisan tinker
>>>factory('App\Profile', 20)->create();

I get the following error:

PHP Recoverable fatal error: Object of class Closure could not be converted to string in C:/laragon/www/definitive/vendor/laravel/framework/src/Illuminate/Support/Str.php on line 338

Any idea how to solve this problem?

If you want to customize any string, it should be outside of create method.

$factory->define(App\Profile::class, function (Faker $faker) {
    $slugName = str_slug($faker->userName);

    $profile = Profile::create([
        'title'     => $faker->userName,
        'gender_id' => 0,
        'role_id'   => 1,
        'slug'      => $slugName,
    ]);

    $slugSentence = str_slug($faker->sentence);
    $profileId = $profile->id;
    for ($i=0; $i < 5; $i++) { 
        $event = Event::create([
            'profile_id'    => $profileId,
            'title'         => $faker->sentence,
            'subtitle'      => $faker->sentence,
            'slug'          => $slugSentence,      
            'category_id'   => 1,
            'language_id'   => 1,
            'video_url'     =>  'video',
            'description'   =>  $faker->paragraph,
        ]);
        $eventId = $event->id;

        for ($i=0; $i < 10; $i++) { 
            $eventcomment = Eventcomment::create([
                'profile_id'    => $profileId,
                'event_id'      => $eventId,
                'body'          =>  $faker->paragraph,
            ]);
        }   
    }

    return $profile;
});

Or You can use Closure attributes