Use define syntax.

database/factories/ModelFactory.php

@@ -11,11 +11,11 @@
 |
 */
 
-$factory['App\User'] = function ($faker) {
+$factory->define('App\User', function ($faker) {
     return [
         'name' => $faker->name,
         'email' => $faker->email,
         'password' => str_random(10),
         'remember_token' => str_random(10),
     ];
-};
+});