Laravel.io
<?php

namespace Tests\Feature;

use App\UseCases\User\RegisterService;
use App\User;
use Illuminate\Contracts\Foundation\Application;
use Illuminate\Foundation\Testing\RefreshDatabase;
use Tests\TestCase;

class CreateUserTest extends TestCase
{
    use RefreshDatabase;

    /**
     * @var Application|mixed
     */
    private $service;

    /**
     * A basic feature test example.
     *
     * @return void
     */
    public function testExample()
    {
        /** @var User $users */
        $user = factory(User::class)->create();

        $this->assertFalse($user->hasVerifiedEmail());

        $user = $this->service->verify($user->id);

        $this->assertTrue($user->hasVerifiedEmail());
    }

    protected function setUp(): void
    {
        parent::setUp(); // TODO: Change the autogenerated stub

        $this->service = resolve(RegisterService::class);
    }
}

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