Call to a member function getRelationExistenceQuery() on null

[Begginer666]

the error appears when i try to run the seeds.

this is the error:

at vendor/laravel/framework/src/Illuminate/Database/Eloquent/Concerns/QueriesRelationships.php:49
45| $method = $this->canUseExistsForExistenceCheck($operator, $count)
46| ? 'getRelationExistenceQuery'
47| : 'getRelationExistenceCountQuery';
48|

49| $hasQuery = $relation->{$method}(
50| $relation->getRelated()->newQueryWithoutRelationships(), $this
51| );
52|
53| // Next we will call any given callback as an "anonymous" scope so they can get the

  +3 vendor frames

4 database/factories/UserFactory.php:59
Illuminate\Database\Eloquent\Model::__callStatic()

  +6 vendor frames

11 [internal]:0
Illuminate\Database\Eloquent\FactoryBuilder::Illuminate\Database\Eloquent{closure}()

this is the factory:

use App\User;
use App\Category;
use App\Product;
use App\Transaction;
use App\Seller;
use Faker\Generator as Faker;
use Illuminate\Support\Str;

$factory->define(User::class, function (Faker $faker) {
static $password;
return [
'name' => $faker->name,
'email' => $faker->unique()->safeEmail,
'email_verified_at' => now(),
'password' => $password ?: $password = bcrypt('secret'),
'remember_token' => Str::random(10),
'verified' => $verificado = $faker->randomElement([User::USUARIO_VERIFICADO, User::USUARIO_NO_VERIFICADO]),
'verification_token'=> $verificado == User::USUARIO_VERIFICADO ? null : User::generarVerificationToken(),
'admin' => $faker->randomElement([User::USUARIO_ADMINISTRADOR, User::USUARIO_REGULAR]),
];
});

$factory->define(Category::class, function (Faker $faker) {
return [
'name' => $faker->word,
'description'=> $faker->paragraph(1),
];
});

$factory->define(Product::class, function (Faker $faker) {
return [
'name' => $faker->name,
'description'=> $faker->paragraph(1),
'quantity'=> $faker->numberBetween(1, 10),
'status'=> $faker->randomElement([Product::PRODUCTO_DISPONIBLE, Product::PRODUCTO_NO_DISPONIBLE]),
'image'=> $faker->randomElement(['1.jgp', '2.jgp', '3.jgp']),
'seller_id'=> User::all()->random()->id,
];
});

$factory->define(Transaction::class, function (Faker $faker) {

$vendedores= Seller::has('products')->get()->random();
$comprador= User::all()->except($vendedores->id)->random();
return [
    'quantity'=> $faker->numberBetween(1, 3),
    'buyer_id'=> $comprador->id,
    'product_id'=> $vendedores->products->random()->id,
];

});

this is the seed:

use Illuminate\Database\Seeder;
use App\User;
use App\Category;
use App\Product;
use App\Transaction;

public function run()
{
DB::statement('SET FOREIGN_KEY_CHECKS = 0');
User::truncate();
Product::truncate();
Category::truncate();
Transaction::truncate();
DB::table('category_product')->truncate();

    $cantidadusuarios= 200;
    $cantidadcategorias= 30;
    $cantidadproductos= 1000;
    $cantidadtransacciones= 1000;

    factory(User:: class, $cantidadusuarios)->create();
    factory(Category:: class, $cantidadcategorias)->create();
    factory(Product:: class, $cantidadtransacciones)->create()->each(
        function($producto)
        {
            $categorias= Category::all()->random(mt_rand(1, 5))->pluck('id');
            $producto->categories()->attach($categorias->first());
        }
    );
    factory(Transaction:: class, $cantidadtransacciones)->create();

}

[staudenmeir]

Your products relationship is missing the return statement.

[Begginer666]

Where is the error? sorry i'm a noob in this.

[staudenmeir]

In the Seller model, you need to add return to the products relationship (return $this->...).

[Begginer666]

im a foolish, i had "$this->hasMany(Product::class);" instead of "return $this->hasMany(Product::class);",
thanks, thats worked