How to deal with legacy system with BDD

1. BDD
FOR LEGACY SYSTEM
Spin Lai

2. Testing

3. Testing, who doesn’t know it?

4. Testing
Unit test
Tests the smallest unit of functionality
Integration test
Test the result combination functions correctly.
Acceptance test
Tests on the full system
to see whether the application's functionality satisfie
s the specification

5. Testing
TDD (Test-driven Development)
BDD (Behavior-driven Development)
FDD (Feature-driven Development)
MDD (Model-driven Development)
DDD (Domain-driven Design)

6. So, what is BDD?

7. Behavior-driven Development
A software development process
Emerged from TDD
Focus on “what” to test rather than “how” to test
Use examples to illustrate behavior
Writing test cases in a natural language that non-
programmers can read
Using Domain Specific Language

8. Gherkin Language

9. Gherkin Language
Use for describe the test scenarios

10. Why BDD?

11. Why BDD ?
Executable specifications
Business needs tie directly to the code
Tests are easier to maintain (stable)

12. Why BDD ?
Provides a common domain language for
User / Stakeholder
Project Manager
Developer
QA
Encourage collaboration between different roles

13. The obstacle : Legacy system

14. Legacy System
It wasn’t designed with automation in mind
Web elements with no identifier or meaningful
classes
Limited control of the source code
Works, but hard to maintain

15. So, how?

16. BDD for legacy system
Think about the capabilities
Group the scenarios
What kind of contexts (the Givens)
What kind of outcomes (the Thens)
The events (the Whens)

17. Tools

18. Tools
Selenium
Behave
PyHamcrest

19. Selenium
Automated web testing framework
Selenium IDE
Selenium Remote Control
Selenium Client API
Selenium WebDriver

20. Selenium Practices
UI Mapping
Page Object design pattern
Three levels of UI test automation

21. Selenium Practices
UI Mapping
Page Object design pattern
Three levels of UI test automation
Source : http://gojko.net/2010/04/13/how-to-implement-ui-testing-without-shooting-yourself-in-the-foot-2/

22. Behave
Feature
Scenario
Step
Tag

23. Behave - Feature
Composed of scenarios
Descriptions
Backgrounds
Tags

24. Behave - Scenario
Describe the behaviors being tested
Composed of a series of steps

25. Behave - Step
Take a line each
Begin with a keyword
“given”
“when”
“then”
“and”
“but”

26. Behave - Tag
Can be used on
Features
Scenarios
Scenario outlines
Used for controlling your test

27. PyHamcrest
Assertion matcher library
Predefined matchers
equal_to
has_properties
contains_string
ends_with
…

28. Show time

29. Recap

30. Recap
BDD isn’t the only way to do testing
Use BDD tools to automate scenarios doesn’t
means you’re doing BDD
Don’t start with tools, start by having
conversations
Don’t stick to the BDD (Gherkin) format to have
conversations

31. References

32. References

33. Q & A