Laravel factory Argument 1 passed to Illuminate\Database\Grammar::parameterize() must be of the type array, string given

Question

I get this error when trying to run a factory in laravel 8. I've looked though several posts about this error but they all seem to come from saving/creating directly incorrectly. Not using a factory. So I am not sure why the factory isn't saving it correctly.

My migration has:

public function up()
{
    Schema::create('posts', function (Blueprint $table) {
        $table->id();
        $table->string('slug');
        $table->string('name');
        $table->longText('desc');
        $table->foreignId('user_id')->constrained();
        $table->timestamps();
        $table->softDeletes();
    });
}

My model has:

class Post extends Model
{
    use HasFactory, SoftDeletes;

    public function user()
    {
        return $this->belongsTo(User::class);
    }

    public function setSlugAttribute($value)
    {
        $this->attributes['slug'] = Str::slug($this->name);
    }
}

My factory has:

public function definition()
{
    return [
        'name' => $this->faker->words,
        'desc' => $this->faker->sentence,
        'user_id' => rand(1,10)
    ];
}

And my Posts seeder has:

public function run()
{
    Post::factory()->times(13)->create();
}

My main DatabaseSeeder runs a user seeder that seeds 10 users. Then a post seeder to seed 13 posts.

I run php artisan migrate:fresh --seed and it fails when it gets to the Post Seeder with this error:

TypeError

Argument 1 passed to Illuminate\Database\Grammar::parameterize() must be of the type array, string given, called in /var/www/html/vendor/laravel/framework/src/Illuminate/Database/Query/Grammars/Grammar.php on line 886

at vendor/laravel/framework/src/Illuminate/Database/Grammar.php:136 132▕ * 133▕ * @param array $values 134▕ * @return string 135▕ */ ➜ 136▕ public function parameterize(array $values) 137▕ { 138▕ return implode(', ', array_map([$this, 'parameter'], $values)); 139▕ } 140▕

  +1 vendor frames    2   [internal]:0
  Illuminate\Database\Query\Grammars\Grammar::Illuminate\Database\Query\Grammars\{closure}("Odio

voluptatem quis facere possimus ut.", "desc")

  +13 vendor frames    16  database/seeders/PostsSeeder.php:17
  Illuminate\Database\Eloquent\Factories\Factory::create()

I'm really not understanding why its expecting an array for a string column.

Answer 1

'name' => $this->faker->words will return an array of words.

You can either call the underlying method and tell it to return a string by passing true as the 2nd argument:

$this->faker->words(3, true) // 3 is the number of words which is the default

or you could use something like sentence

$this->faker->sentence

words() documentation