If you're using Laravel Jetstream with teams, you may have found you're getting the "ErrorException: Trying to get property 'id' of non-object" a whole lot during testing. This is because when you create a User from a factory, the team and team_user pivot table are not automatically created or filled.

To fix this create a TeamFactory, and create the new user within the definition() method:

public function definition()
    {
        return [
            'user_id' => User::factory()->create(),
            'name' => $this->faker->words(2, true),
            'personal_team' => true,
        ];
    }

Then, add the HasFactory trait to your Team model:

use HasFactory

And when you need to seed a User, seed a Team instead:

Team::factory()->create();

TIP: A common usecase of the TestCase class is to create a signIn() method to use in your PHPUnit tests. You can still do that by changing your signIn method to the following:

public function signIn($user = null)
    {
        $team = Team::factory()->create();

        $this->actingAs($user ?: $user = User::whereId($team->user_id)->first());

        return $user;
    }