Seed method works only once in Test classes

Hello everybody!

I encounter a weird issue using Artisan commands (directly or indirectly) in the setUp method of my integration test classes. In order to get test data, I want to migrate and seed data in a test database before running my tests. To do so, I use the setUp method:

    public function setUp(): void
    {
        parent::setUp();

        $this->seed();
    }

I also use the RefreshDatabase trait in order to empty my database before each test.

The first test runs perfectly and works as expected. Then, all other tests fail because of a CommandNotFoundException thrown in $this->seed();. I tried to use the debugger to find out what happens and saw that only two commands are loaded during the second test execution: list and help.

I really don't understand what happens here. Am I missing something?

Here is an example test class which fails:

class TVShowAPITest extends TestCase
{
    use RefreshDatabase;

    public function setUp(): void
    {
        parent::setUp();

        $this->seed();
    }

    public function testGetAllUnauthenticated()
    {
        $response = $this->get('/api/tvshows');
        $response->assertStatus(200)->assertJson([
            'meta' => [
                'last_page' => 2,
                'to' => 25,
                'total' => 30
            ]
        ]);
    }

    public function testGetAllAuthenticatedAsSuperadmin()
    {
        $superAdmin = User::where('username', env('SUPERADMIN_USERNAME', 'superadmin'))->firstOrFail();
        Passport::actingAs($superAdmin);
        $responseWhisp = $this->get('/api/tvshows');
        $responseWhisp->assertStatus(200)->assertJson([
            'meta' => [
                'last_page' => 6,
                'to' => 25,
                'total' => 120
            ]
        ]);
    }
}

Thanks in advance for your help!