This document discusses Behavior-Driven Development (BDD) and how it can improve software development. BDD is a methodology that uses examples in natural language to define desired software behaviors and tests those examples throughout development. It aims to bridge communication gaps between developers, testers, and business stakeholders. The document outlines BDD processes and how they differ from traditional waterfall and test-driven development. It also provides an example template for writing BDD scenarios in Gherkin, a domain-specific language.

6. IASI, 10th May, 2014
Behavior-Driven Development
with
&
Remus Langu

7. Why should we
be interested in BDD?
Code
Developer

8. Why should we
be interested in BDD?
Code
Developer
1
Test
Tester

9. Why should we
be interested in BDD?
Code
Developer
1
Test
Tester
Bug
2

10. Why should we
be interested in BDD?
Code
Developer
1
Test
Tester
2
3

11. Why should we
be interested in BDD?
Code
Developer
1
Test
Tester
Bug
3
2 4

12. Why should we
be interested in BDD?
Code
Developer
1
Test
Tester
3 5
2 4

13. Why should we
be interested in BDD?
Code
Developer
1
Test
Tester
3 5
2 4
Bug
6 ....

14. The Ping-Pong Problem
Code
Developer
Test
Tester
Ping
Pong

15. Queuing Theory
Feedback
Testing
Process
Dev
Process

16. Queuing Theory
Feedback
Testing
Process
Dev
Testing
Process

17. Test-First Development
Developer
Unit
Test
Code
Failed
Passed

18. Test-Driven Development
Failed
Unit
Test Code
Passed
Design
Refactor
Developer
Kent Beck

20. TDD Studies in Industry
40-90 Defect Density
15-35 Development Time

21. Related TDD Studies in Academia
Study # programmers Quality effects Productivity
effects
Edwards¹
(Virginia Tech 2003)
59 54%
fewer defects
N/A
Kaufmann²
(Bethel 2003)
8 Improved
information
flow
50%
improvement
Erdogmus³
(Torino 2005)
35 no change 28%
improvement
1. “Rethinking Computer Science Education from a Test-first Perspective”, OOPSLA
2. “Implications of test-driven development: a pilot study”, OOPSLA
3. “On the Effectiveness of Test-first Approach to Programming”, IEEE Trans on SE

22. Projects developed with TDD
Fit: Framework for Integrated Test
MSBuild

23. Test-Driven Development
Failed
Unit
Test Code
Passed
Design
Refactor
Developer

24. Behavior-Driven Development
Failed
Unit Test Code
TDD
Refactor Passed
Design
Feature
Test
Failed
BDD
Passed
Dan North

25. BDD cuts the Costs from
WATERFAILL
Code
CODING Test
TESTING
Req.
ANALYSIS
Bug
Untestable
Unwanted
UML
DESIGN

26. BDD cuts the Costs from
WATERFAILL
$$$
Time
Cost of Change

27. BDD cuts the Costs from
WATERFAILL
$$$
Time
Cost of Change

28. BDD cuts the Costs from
WATERFAILL
$$$
Time
Cost of Change

29. Ubiquitous Language
Tester
Developer
Business
Analyst
Customer
Designer
UI Designer
DSL

30. How BDD transforms
an Idea to Working Software
Business
Value
Customer
Vision
Feature
Sets
Scenarios Stories
Code
UI
Design
DSL
Tester
Business
Analyst
UI Designer
Domain
Developer Expert

31. BDD Definition
“BDD is a second-generation,
outside-in, pull-based, multiple-stakeholder,
multiple-scale, high-automation,
agile methodology.”

32. BDD Overview
TDD
ATDD
DDD
NLP
2nd Generation
User Interaction Outside In
Business Value
MMFs
Multiple Scale
Pull-based
Multiple Stakeholders
High Automation
Agile Methodology
BDD

33. How do I do it as a Developer?
Behavior-Driven Development
DEMO
with
&

34. Conclusion
Customer
Failed
BDD
Passed
Acceptance
Test
Tester
Developer
Unit Test Failed
Code
TDD
Refactor Passed
Design
Business
Analyst
UI Designer

35. A network of
PREMIUM people.
REMUS LANGU
Senior Software Engineer | Speaker | Trainer
Husband | Father | Orthodox Christian
RemusLangu@yahoo.com

36. Recommendations
Dan North
How to sell BDD to the business
Liz Keogh
Don't let your process hide your ignorance

37. IASI, 10th May, 2014
THANK YOU
Your questions are welcome

39. Gherkin
Domain Specific Language Template
Feature: Title - one line
describing the story
In order to [benefit]
As a [role]
I want to [feature]
Scenario: Title
Given [context]
And [some more context]…
When [an event occurs]
Then [outcome]
And [another outcome]…