Laravel 5.4 DatabaseMigrations issue

While running tests using in-memory sqlite, i'm getting a "no such column" error while using this code:

class myCoolTest extends TestCase
{
use DatabaseMigrations;

protected $user;

public function setUp()
{
    parent::setUp();
    #$this->artisan('migrate'); <-- if I uncomment this and comment DatabasseMigrations trait, everything works
    $this->user = factory(User::class)->create();
}

function test_name() {
	// test here
}

phpunit.xml contains:

<env name="DB_CONNECTION" value="sqlite"/>
<env name="DB_DATABASE" value=":memory:"/>

Any ideas?