BDD is an extension of the good-known and widely used TDD methodology. It improves TDD's efficiency and fixes its most common problems by allowing developers to focus on the essence of programming. It also allows to improve the communication between software engineers and business professionals, making the whole development process easier and more effective.

1. 1
WHY YOU SHOULD BE
DOING BDD
MATEUSZ ZALEWSKI
@mpzalewski
https://github.com/Zales0123

2. BDD is a process designed to aid the management and the delivery of software
development projects by improving communication between engineers and
business professionals.
BEHAVIOR DRIVEN
DEVELOPMENT
2
http://inviqa.com/insights/bdd-guide

3. 3
TEST BEHAVIOR
https://worldviewofjesus.files.wordpress.com/2015/02/evolution.jpg

4. 4
✦ “There is no time”
✦ “It’s unnecessary extra code”
✦ “I know what I’m writing”
✦ “Client wants visible effect”
✦ and many more…

5. BENEFITS
5

6. COMMUNICATION
6
REQUIREMENTS CODE

7. 7
कोड байт
MONEY CODE BYTE

8. 8
कोड байт
MONEY CODE BYTE
UBIQUITOUS LANGUAGE

9. Value
Time
9
NOEFFICIENCY

10. Value
Time
10
EFFICIENCY

11. HOW?
11

12. FAILING
PASSEDREFACTOR
12

13. NO TESTS
NO REFACTORING
13

14. 14
GOAL
We are going to
increase sale by
selling more
products

15. We are going to
increase sale by
selling more
products
GOAL
We are planning to
achieve a 10% increase
in sale in our web store
in 4 months
15

16. EXAMPLES
Given "PHP T-Shirt" is priced at €100.00
And the store has "VAT" tax rate of 23%
When I add product "PHP T-Shirt" to the cart
Then my cart taxes should be €23.00
16

17. LESS AMBIGUITY
=
LESS MISUNDERSTANDINGS
17

18. 18
SPECIFICATION
STORY
How class should work
Application business logic

19. DON’T TEST, DESCRIBE
19

20. 20
✦ it adds two numbers
✦ it multiplies two numbers
✦ it subtracts two numbers
✦ it divides two numbers
✦ it not allows to divide by 0
WHAT DOES
CALCULATOR DO?

21. 21
HOW HARD CAN IT BE?
class CalculatorSpec extends ObjectBehavior
{
function it_adds_two_numbers()
{
$this->add(4, 5)->shouldReturn(9);
}
function it_multiplies_two_numbers()
{
$this->multiply(3, 8)->shouldReturn(24);
}
function it_does_not_allow_to_divide_by_0()
{
$this
->shouldThrow(‘InvalidArgumentException’)
->during(‘divide’, [10, 0])
;
}
}

22. 22
class ValidationMessageProviderSpec extends ObjectBehavior
{
function it_provides_happy_message_if_validation_passed(
Validator $validator,
ValidatedObject $object
) {
$validator->validate($object)->willReturn(true);
$this->provide($object)->shouldReturn(‘Great! Everything is fine!’);
}
}
HAVING FUN WITH MOCKS

23. THINK IN CODE
CODE IS GOOD
23
http://phpsrbija.rs/tday2014/img/portfolio/phpspec.png

24. STORY
24
It is an ancient need to be told stories. But the
story needs a great storyteller.
~ Alan Rickman

25. FEATURE
25
WHY? (BUSINESS VALUE)
WHO? (BENEFICIARY)
WHAT? (FEATURE DESCRIPTION)

26. FEATURE
26
In order to pay less while buying goods
As a Customer
I want to receive discount for my purchase
Receiving percentage discount promotion on order

27. SCENARIO
27
Given "PHP T-Shirt" is priced at €100.00
And the store has "VAT" tax rate of 23%
When I add product "PHP T-Shirt" to the cart
Then my cart taxes should be €23.00

28. BEHAT
28
https://github.com/Behat/Behat
✦ uses Gherkin structured
language
✦ used to describe application
business logic
✦ really impressive

29. 29
✦ Behat (PHP)
✦ PHPSpec (PHP)
✦ Cucumber (Ruby)
✦ JBehave (Java)
✦ Spock (Groovy)
✦ SpecFlow (.NET)
TOOLS

30. 30
Have no fear of perfection - you’ll never reach it.
~ Salvador Dali

31. THANK YOU
31
@mpzalewskihttps://github.com/Zales0123