Advanced TDD

If you love TDD and want to improve in this programming discipline, you're in the right place. Attend this talk, and you'll learn about:

- What TDD really is
- Techniques for making your test suite more reliable
- What does getting stuck mean, and how to get out of it
- Why mocking is more about collaboration
- Acceptance tests and more!

Transcript

1. ADVANCED TDD
   Diego Aguiar Beltrán
   @MolloKhan
   

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2. ➢ Developer at SymfonyCasts
   ➢ Hiking
   ➢ Gaming (Warcraft FTW!)
   ➢ Tepic, Mexico
   Diego Aguiar Beltrán
   @MolloKhan
   

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3. Main Topics
   ➢ What TDD Really is
   ➢ Useful TDD Techniques
   ➢ What “Getting Stuck” means
   ➢ When Not to TDD
   

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4. What is TDD?
   ➢ Programming Methodology
   ➢ It’s Composed of 3 Laws
   ➢ Tests Always Go First
   ➢ Red, Green, Refactor cycle
   

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5. TDD is more like a
   discipline
   

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6. ➢ Practice, practice, practice…
   ➢ Train Your Mind
   ➢ Tests Go First
   

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7. A bit of History…
   ➢ Kent Beck inventor of TDD
   ➢ Invented In the late 1990’s
   ➢ As a way to write better quality code
   

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8. TDD
   Techniques
   ➢ Fake it till you make it
   ➢ Triangulation
   ➢ Assert First
   

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9. Fake it till you make it
   

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10. Name Inverter
    Example
    “Diego Aguiar” → “Aguiar, Diego”
    Fake it till you make it
    

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11. Where to start?
    Fake it till you make it
    

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12. Fake it till you make it
    public function testNullCase()
    {
    $name = null;
    $invertedName = $this->nameInverter
    ->invert($name);
    self::assertEquals('', $invertedName);
    }
    public function invert($name)
    {
    // Forcing test to pass
    return ‘’;
    }
    TEST CODE PRODUCTION
    

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13. public function invert($name)
    {
    return 'Diego';
    }
    PRODUCTION
    Fake it till you make it
    public function testSingleName()
    {
    $name = 'Diego';
    $invertedName = $this->nameInverter
    ->invert($name);
    self::assertEquals(
    'Diego',
    $invertedName
    );
    }
    TEST CODE
    

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14. Fake it till you make it
    PRODUCTION
    public function invert($name)
    {
    if (!$name) {
    return '';
    }
    return $name;
    }
    

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15. Triangulation
    

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16. Triangulation
    class NameInverterTest extends TestCase
    {
    public function testNullCase()
    {
    $invertedName = $this->nameInverter->invert(null);
    self::assertEquals('', $invertedName);
    }
    public function testSingleName()
    {
    $invertedName = $this->nameInverter->invert('Diego');
    self::assertEquals('Diego', $invertedName);
    }
    }
    

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17. Fake it till you make it
    &
    Triangulation
    The Best of Friends
    

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18. Assert First
    

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19. Assert First
    class NameInverterTest extends TestCase
    {
    public function testFullName()
    {
    $name = 'Diego Aguiar';
    $invertedName = $this->nameInverter
    ->invert($name);
    self::assertEquals('Aguiar, Diego', $invertedName);
    }
    }
    

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20. Getting
    Stuck
    

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21. Why does
    it happen?
    ➢ It’s a symptom of a problem
    ➢ Production code is too specific
    ➢ You wrote the wrong test
    ➢ Aiming for the goal too fast
    

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22. How to get
    Unstuck
    ➢ Step up and think for a simpler test
    ➢ Refactor hard-to-test code
    ➢ Write a list of use-cases
    ➢ Ignore testing for a moment
    

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23. When Not
    to TDD
    ➢ Configuration
    ➢ Discovering
    ➢ Repository Queries
    

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24. ➢ TDD is more like a discipline
    ➢ There are techniques to get you unstuck
    ➢ TDD is a tool, not a rule
    Conclusion
    @MolloKhan
    

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25. Happy TDD!
    @MolloKhan
    “One test a day keeps bugs away"
    

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26. Z zero (or empty case)
    O one
    M many
    B boundaries
    I interfaces
    E exceptions
    BONUS!!
    https://i.ytimg.com/vi/0xRCYmbvfEs/maxresdefault.jpg
    

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27. Happy TDD!
    @MolloKhan
    THANK YOU AGAIN!
    

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