Testing Wizardry: How Mocks and Fixtures Can Save Your Sanity

Writing tests is easy. Writing tests that are thorough is hard. How do you test in isolation? It is a tough question when you start your testing journey, but with mocks and fixtures you too will be writing impressive and useful tests. In this talk we will explore native PHPUnit techniques for creating mocks and stubs, Phake and Mockery for enhanced mocking in unit tests, Phactory for fixture generation in unit tests, and Phabric for feature tests with Behat. At the end of this talk you will have gained knowledge of how and when to apply mocks and fixtures, and will be on your way to being a testing phreak.

Transcript

1. Testing Wizardry
   how mocks and fixtures can save your sanity
   Jeff Carouth #ZendCon 2012
   

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2. Jeff Carouth
   tweets jcarouth
   blogs http://carouth.com
   checks jcarouth@gmail.com
   works
   

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3. Writing Tests
   Is easy
   

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4. Is more difficult
   Writing Effective Tests
   

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5. Unit Tests Vs. Integration Tests
   

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6. Fake or Simulated
   object exposing the same
   interface
   as the object it mimics
   

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7. Why Mocks?
   Objects which have states that are difficult to create
   or reproduce.
   

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8. Mocks and Stubs with PHPUnit
   http://crth.net/phpunit-mock-docs
   

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9. interface MyInterface
   {
   public function sayHi();
   }
   class FirstMockTest extends PHPUnit_Framework_TestCase
   {
   public function testJeffShouldBeAbleToMockHisInterface()
   {
   $mockMyInterface = $this->getMock('MyInterface');
   $mockMyInterface->expects($this->any())
   ->method('sayHi')
   ->will($this->returnValue('Oh, hi!'));
   $this->assertEquals('Oh, hi!', $mockMyInterface->sayHi());
   }
   }
   

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10. Stubs (in PHPUnit) Can:
    returnValue(‘hello world!’)
    returnArgument(1)
    returnSelf()
    returnValueMap($map)
    returnCallback(‘str_rot13’)
    throwException(new OopsException())
    

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11. class OrderTest extends PHPUnit_Framework_TestCase
    {
    public function testSaveOrderSendsEmailWithOrderConfirmation()
    {
    $order = new Order(new \EmailService\Service\Sendmail());
    $order->setId(12345);
    $order->save();
    // log into email account
    // find email in inbox
    // verify it has the correct subject
    // No. No. No.
    }
    }
    NO!
    

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12. class OrderTest extends PHPUnit_Framework_TestCase
    {
    public function testSaveOrderSendsEmailWithOrderConfirmation()
    {
    $mockEmailService = $this->getMock(
    '\\EmailService\\EmailServiceInterface'
    );
    $mockEmailService->expects($this->once())
    ->method('send');
    $order = new Order($mockEmailService);
    $order->setId(12345);
    $order->save();
    }
    }
    

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13. class Order
    {
    private $emailService;
    private $logger;
    private $id;
    public function __construct($service, $logger = null)
    {
    $this->emailService = $service;
    $this->logger = $logger;
    }
    public function save()
    {
    //do some saving logic
    $this->emailService->send(
    'Order Confirmation #' . $this->id
    );
    }
    }
    

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14. class OrderTest extends PHPUnit_Framework_TestCase
    {
    //...snip...
    public function testEmailConfirmationFailLogs()
    {
    $mockLogger = $this->getMock('\\System\\LoggerInterface');
    $mockLogger->expects($this->once())
    ->method('log');
    $mockEmailService = $this->getMock(
    '\\EmailService\\EmailServiceInterface'
    );
    $mockEmailService->expects($this->once())
    ->method('send')
    ->will($this->throwException(new Exception()));
    $order = new Order($mockEmailService, $mockLogger);
    $order->setId(12345);
    $order->save();
    }
    }
    

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15. class Order
    {
    public function save()
    {
    //do some saving logic
    try {
    $this->emailService->send(
    'Order Confirmation #' . $this->id
    );
    } catch (Exception $e) {
    if (null !== $this->logger) {
    $this->logger->log(
    "email failed for order {$this->id}"
    );
    }
    }
    }
    }
    

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16. Phake
    http://phake.digitalsandwich.com/docs/html/
    

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17. class OrderTest extends PHPUnit_Framework_TestCase
    {
    public function testSaveOrderSendsEmailWithOrderConfirmation()
    {
    $mockEmailService = Phake::mock(
    '\\EmailService\\EmailServiceInterface'
    );
    Phake::when($mockEmailService)->send()->thenReturn(true);
    $order = new Order($mockEmailService);
    $order->setId(12345);
    $order->save();
    Phake::verify($mockEmailService)->send();
    }
    }
    

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18. Mockery
    https://github.com/padraic/mockery
    

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19. class OrderTest extends PHPUnit_Framework_TestCase
    {
    public function tearDown()
    {
    m::close();
    }
    public function testSaveOrderSendsEmailWithOrderConfirmation()
    {
    $mockEmailService = \Mockery::mock(
    '\\EmailService\\EmailServiceInterface'
    );
    $mockEmailService->shouldReceive('send')
    ->withAnyArgs()
    ->andReturn(true);
    $order = new Order($mockEmailService);
    $order->setId(12345);
    $order->save();
    }
    }
    

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20. Fixtures Defined
    

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21. DbUnit
    

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22. class TodoListTest extends PHPUnit_Extensions_Database_TestCase
    {
    private $pdo;
    /**
    * @return PHPUnit_Extensions_Database_DB_IDatabaseConnection
    */
    public function getConnection()
    {
    $this->pdo = new PDO('DSN', 'USER', 'PASS');
    return $this->createDefaultDBConnection(
    $this->pdo, 'todolist');
    }
    /**
    * @return PHPUnit_Extensions_Database_DataSet_IDataSet
    */
    public function getDataSet()
    {
    return $this->createFlatXMLDataSet(
    __DIR__ . "/fixtures/todo-seed.xml");
    }
    }
    

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23. 
    
    completed="false" />
    completed="false" />
    completed="false" />
    completed="false" />
    
    

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24. class TodoListTest extends PHPUnit_Extensions_Database_TestCase
    {
    public function testGetCountReturnNumberOfUnfinishedTasks()
    {
    $todoModel = new TodoModel($this->pdo);
    $expectedNumberOfTodos = 4;
    $todos = $todoModel->getUnfinishedTasks();
    $this->assertCount(
    $expectedNumberOfTodos,
    $todos,
    'The expected number of unfinished tasks is wrong.'
    );
    }
    }
    

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25. class TodoModel
    {
    private $db;
    public function __construct($db)
    {
    $this->db = $db;
    }
    public function getUnfinishedTasks()
    {
    $sql = "SELECT * FROM todo";
    $result = $this->db->query($sql);
    return $result->fetchAll();
    }
    }
    

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26. Phabric
    https://github.com/benwaine/Phabric
    

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27. class FeatureContext extends MinkContext
    {
    protected $phabric;
    public function __construct(array $parameters)
    {
    $config = new \Doctrine\DBAL\Configuration();
    self::$db = \Doctrine\DBAL\DriverManager::getConnection(...);
    $datasource = new \Phabric\Datasource\Doctrine(
    self::$db, $parameters['Phabric']['entities']
    );
    $this->phabric = new Phabric\Phabric($datasource);
    }
    }
    

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28. Feature:
    As an organized person
    I want to be able to manage my todo list
    So that I can ensure I accomplish my tasks
    Scenario: I want to see all incomplete tasks
    Given The following tasks exist
    | summary | createdDate | completed | estimate |
    | Task 1 | 2012-09-21 19:53:33 | false | 1 |
    | Task 2 | 2012-09-21 19:53:33 | false | 1 |
    | Task 3 | 2012-09-21 19:53:33 | false | 1 |
    When I am on "/tasks"
    Then I should see "3" tasks
    /**
    * @Given /^The following tasks exist$/
    */
    public function theFollowingTaskssExist(TableNode $table)
    {
    $this->phabric->insertFromTable('tasks', $table);
    }
    

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29. Faker
    https://github.com/fzaninotto/Faker
    

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30. require_once __DIR__ . "/vendor/autoload.php";
    $faker = Faker\Factory::create();
    print '' . PHP_EOL;
    print '' . PHP_EOL;
    for ($i = 0; $i < 50; $i++) {
    print " firstName}\" " .
    "lastname=\"{$faker->lastName}\" " .
    "email=\"{$faker->email}\" />" . PHP_EOL;
    }
    print '';
    

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31. 
    
    email="vvon@yahoo.com" />
    email="qmetz@veum.org" />
    email="hartmann.aliyah@langworthokuneva.com" />
    email="leffler.elena@gmail.com" />
    email="rwaelchi@hotmail.com" />
    email="rconroy@gmail.com" />
    email="maximus.grady@hotmail.com" />
    
    
    

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32. Thank You!
    https://joind.in/7039
    @jcarouth | jcarouth@gmail.com
    http://speakerdeck.com/jcarouth
    

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