Embracing TDD - A Beginner's approach to get acquainted with TDD workflow

Developers, hate testing with the common reason of boredom, ego or "waste of time". TDD looks overwhelming at first. But, it gives you more than what it takes from you. TDD is considered to be a methodology, but moreover it is an approach, a process that we need to embrace. It’s a rather a shift of paradigm, a BIG change, and from my experience, I can say that no change is easy. I believe, any good change goes through following stages -> Rejection, Ignorance and then, finally ACCEPTANCE. I will share my journey with you on how I embraced TDD; the difficulties I faced and how it made me a better developer. In this talk, I will also give a glimpse of basics of TDD as well as what would be a good place to start implementing it.

Transcript

1. E M B R A C I N G T D D
   - N O V I C E T O I N T E R M E D I AT E
   

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2. S H O R T S T O RY
   

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3. I D E A - > I M PA C T
   

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4. V I R A J K H ATAV K A R
   • Founder, Tantra-Gyan ( T-G )
   • PHP Services
   • Joomla Development
   • WordPress Development
   • UI / UX Design and
   Development
   • Angular
   

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5. V I R A J K H ATAV K A R
   • Founder, Tantra-Gyan ( T-G )
   • PHP Services
   • Joomla Development
   • WordPress Development
   • UI / UX Design and
   Development
   • Angular
   • @virajkhatavkar
   • viraj@tantra-gyan.com
   

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6. “As a software developer we should be
   solving the right problems for
   businesses”
   

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7. C A M B R I D G E U N I V E R S I T Y S T U D Y
   S TAT E S S O F T WA R E B U G S C O S T
   E C O N O M Y $ 3 1 2 B I L L I O N
   

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8. C H A L L E N G E S
   • Code riddled with defects
   • Nightmare to maintain, slow to develop
   • Failing to meet actual needs
   

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9. C H A L L E N G E S
   • Code riddled with defects
   • Nightmare to maintain, slow to develop
   • Failing to meet actual needs
   

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10. C H A L L E N G E S
    • Code riddled with defects
    • Nightmare to maintain, slow to develop
    • Failing to meet actual needs
    

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11. S O L U T I O N : T E S T I N G
    

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12. D E S I G N C O D E T E S T
    

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13. T E S T I N G AT L A S T M AY L E AV E
    H O L E S I N Y O U R T E S T C O V E R A G E
    

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14. W R I T E A
    FA I L I N G
    T E S T
    

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15. W R I T E A
    FA I L I N G
    T E S T
    M A K E T H E
    T E S T PA S S
    

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16. W R I T E A
    FA I L I N G
    T E S T
    M A K E T H E
    T E S T PA S S
    R E FA C T O R
    

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17. W R I T E A
    FA I L I N G
    T E S T
    M A K E T H E
    T E S T PA S S
    R E FA C T O R
    TDD
    

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18. O N LY E V E R W R I T E C O D E
    T O F I X A FA I L I N G T E S T
    

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19. public function test_create_project_class_is_initializable()

    {
    

    $project = new CreateProject();

    

    $this->assertInstanceOf(CreateProject::class, $project);
    

    }
    Create a new class
    

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20. class CreateProject

    {
    }
    Create a new class
    

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21. L I V E D E M O
    

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22. M Y F R U S T R AT I O N W H I L E D O I N G T H I S
    

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23. T H E S I M P L E I D E A O F W R I T I N G T E S T S
    B E F O R E C O D E D E M O L I S H E D M Y
    C O N C E P T O F P R O G R A M M I N G
    

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24. “TDD is a mindset, it's the way you
    approach a project not just how you test
    it. It happens to result in a fully
    automated set of unit tests, but these
    unit tests are side effects , not the
    ultimate goal”
    

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25. PAY M E N T G AT E WAY
    

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26. public function processPayment(array $paymentDetails)

    {

    $transaction = new \CCAvenue(self::API_ID, self::TRANS_KEY);

    $transaction->amount = $paymentDetails['amount'];

    $transaction->card_num = $paymentDetails['card_num'];

    $transaction->exp_date = $paymentDetails['exp_date'];

    

    $response = $transaction->authorizeAndCapture();

    

    return $response->approved ? true : false;

    }
    #Payment Class
    

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27. public function testProcessPaymentReturnsTrueOnSuccessfulPayment()

    {

    $paymentDetails = [

    'amount' => 123.99,

    'card_num' => '4111-1111-1111-1111',

    'exp_date' => '03/2013',

    ];

    

    $payment = new Payment();

    $result = $payment->processPayment($paymentDetails);

    

    $this->assertTrue($result);

    }
    

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28. FAILURES!
    Tests: 1, Assertions: 1, Failures: 1.
    

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29. public function processPayment(array $paymentDetails)

    {

    $transaction = new \CCAvenue(self::API_ID, self::TRANS_KEY);

    $transaction->amount = $paymentDetails['amount'];

    $transaction->card_num = $paymentDetails['card_num'];

    $transaction->exp_date = $paymentDetails['exp_date'];

    

    $response = $transaction->authorizeAndCapture();

    

    return $response->approved ? true : false;

    }
    #Payment Class
    

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30. public function processPayment(array $paymentDetails)

    {

    $transaction = new \CCAvenue(self::API_ID, self::TRANS_KEY);

    $transaction->amount = $paymentDetails['amount'];

    $transaction->card_num = $paymentDetails['card_num'];

    $transaction->exp_date = $paymentDetails['exp_date'];

    

    $response = $transaction->authorizeAndCapture();

    

    $response->approved ? true : false;

    }
    #Payment Class
    

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31. T E S T D O U B L E S
    • A test double is an object that can stand n
    for a real object in a test, similar to how a
    stunt double stands in for an actor in a
    movie.
    

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32. T E S T D O U B L E S
    • Dummy
    • Stub
    • Spy
    • Mock
    • Fake
    

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33. T E S T D O U B L E S
    • Dummy
    • Stub
    • Spy
    • Mock
    • Fake
    

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34. M O C K O B J E C T I S A C L O N E O F A N
    O B J E C T W H I C H W E C A N U S E T O
    S I M P L I F Y O U R T E S T S
    

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35. C L A S S
    

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36. C L A S S D E P E N D E N C Y
    

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37. C L A S S
    T E S T
    C L A S S
    D E P E N D E N C Y
    

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38. C L A S S
    T E S T
    C L A S S
    D E P E N D E N C Y
    M O C K E D
    D E P E N D E N C Y
    

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39. C L A S S
    T E S T
    C L A S S
    D E P E N D E N C Y
    M O C K E D
    D E P E N D E N C Y
    

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40. M O C K E RY
    • use Mockery;
    • $mock = Mockery::mock( SomeClass );
    

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41. public function test_example_of_mocked_class()

    {

    $mock = Mockery::mock( SomeClass::class );

    

    $mock->shouldReceive('method')->once();

    }
    

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42. public function processPayment(array $paymentDetails)

    {

    $transaction = new \CCAvenue(self::API_ID, self::TRANS_KEY);

    $transaction->amount = $paymentDetails['amount'];

    $transaction->card_num = $paymentDetails['card_num'];

    $transaction->exp_date = $paymentDetails['exp_date'];

    

    $response = $transaction->authorizeAndCapture();

    

    return $response->approved ? true : false;

    }
    #Payment Class
    

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43. $mock = Mockery::mock( CCAvenue::class );
    

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44. public function processPayment(array $paymentDetails)

    {

    $transaction = new \CCAvenue(self::API_ID, self::TRANS_KEY);

    $transaction->amount = $paymentDetails['amount'];

    $transaction->card_num = $paymentDetails['card_num'];

    $transaction->exp_date = $paymentDetails['exp_date'];

    

    $response = $transaction->authorizeAndCapture();

    

    return $response->approved ? true : false;

    }
    #Payment Class
    

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45. D E P E N D E N C Y
    I N J E C T I O N
    

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46. public function processPayment(\CCAvenue $transaction, array $paymentDetails)

    {

    $transaction->amount = $paymentDetails['amount'];

    $transaction->card_num = $paymentDetails['card_num'];

    $transaction->exp_date = $paymentDetails['exp_date'];

    

    $response = $transaction->authorizeAndCapture();

    

    return $response->approved ? true : false;

    }
    #Payment Class
    

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47. public function testProcessPaymentReturnsTrueOnSuccessfulPayment()

    {

    //Test

    }
    

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48. public function testProcessPaymentReturnsTrueOnSuccessfulPayment()

    {

    $paymentDetails = [

    'amount' => 123.99,

    'card_num' => '4111-1111-1111-1111',

    'exp_date' => '03/2013',

    ];

    }
    

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49. 

    $mock = Mockery::mock(\CCAvenue::class);
    

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50. $mock = Mockery::mock(\CCAvenue::class);

    

    $mock->shouldReceive('authorizeAndCapture')

    ->once()

    ->andReturn(true);
    

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51. $mock = Mockery::mock(\CCAvenue::class);

    

    $mock->shouldReceive('authorizeAndCapture')

    ->once()

    ->andReturn(true);

    

    $payment = new Payment();

    $result = $payment->processPayment($mock,
    $paymentDetails);
    

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52. $mock = Mockery::mock(\CCAvenue::class);

    

    $mock->shouldReceive('authorizeAndCapture')

    ->once()

    ->andReturn(true);

    

    $payment = new Payment();

    $result = $payment->processPayment($mock,
    $paymentDetails);

    

    $this->assertTrue($result);
    

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53. public function testProcessPaymentReturnsTrueOnSuccessfulPayment()

    {

    $paymentDetails = [

    'amount' => 123.99,

    'card_num' => '4111-1111-1111-1111',

    'exp_date' => '03/2013',

    ];

    

    $mock = Mockery::mock(\CCAvenue::class);

    

    $mock->shouldReceive('authorizeAndCapture')

    ->once()

    ->andReturn(true);

    

    $payment = new Payment();

    $result = $payment->processPayment($mock, $paymentDetails);

    

    $this->assertTrue($result);

    }
    

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54. “The motivation for mocks is design, not
    testing”
    

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55. “Mocks should guide you to design how
    your objects talk to each other”
    

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57. - K O N S TA N T I N K U D R A S H O V
    “Example of life is journey, not a
    destination. Life is more about how we
    approach problems and solve them.
    Why don’t we apply the same in
    software design ?”
    

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58. “A system is not the sum of its parts. It’s
    the product of it’s interactions…”
    

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59. B E I N G T E S T D R I V E N
    • High quality with TDD
    • Quality comes in many flavours
    • Less time spent fixing defects
    

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60. W H AT ’ S I N I T F O R M E ?
    • No more long debugging sessions
    • Feeling confident with my work
    • More time for other stuff
    

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61. T D D - T H E G R A N D I D E A
    • Small incremental steps
    • Evolutionary design
    • Keeping code healthy with refactoring
    

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62. I M P O R TA N T P O I N T S
    • Your tests should drive your design.
    • TDD exposes your design problems.
    • OOP is about communication between
    objects and TDD helps you in creating
    clear communications.
    

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63. T E S T D R I V E N D E S I G N
    

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64. T E S T D R I V E N D E S I G N
    

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65. Q U E S T I O N S ? ? ?
    

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