phpUnitTests.php

<?php
 
namespace Tests;
 
use PHPUnit\Framework\TestCase;
 
class UserRegistrationTest extends TestCase
{
 
    public function tearDown()
    {
        parent::tearDown();
        \Mockery::close();
    }
 
    public function test_withRightData_insertsUser()
    {
        $email = 'foo@bar.lv';
        $password = 'super secret';
 
        $repo = \Mockery::mock(new UserRepository());
        $repo->shouldReceive('addUser')->with($email, $password)->once()->andReturn(3);
        $service = new UserRegistrationService($repo);
        $id = $service->registerUser($email, $password);
 
        $this->assertEquals(3, $id);
 
    }
}
 
class UserRegistrationService
{
    /**
     * @var UserRepository
     */
    private $userRepository;
 
    public function __construct(UserRepository $userRepository)
    {
        $this->userRepository = $userRepository;
    }
    public function registerUser(string $email, string $password)
    {
        // validation
 
        // insert
        $userId = $this->userRepository->addUser($email, $password);
 
        // send email
        return $userId;
    }
}
 
class UserRepository
{
    public function addUser(string $email, string $password)
    {
        var_dump(123);
        // super heavy DB query
        //...
        return 3;
    }
}