TDD – do increasing and save...

Who I am?

Programmer at Wargaming.net~ 5 years php experience

Disclaimer

TDD - ?...

TDD this is...

...or this?! Do you know it?

Expectations...

Reality...

Why not?...

TDD? And who will

pay for it?

TDD does not work

everywhere

Good thing! But

we release

very soon

Stress-free!

0 1 2 3 4 5 6 70

2

4

6

8

10

12

Plain

TDD

Why is that?...

- Start immediately- Test First- SOLID/Patterns- Less coupled systems- Stress control. Results are obvious ...

Test First...

SOLID

Single Responsibility

Open/Closed

Liskov Substitution

Interface Segregation

Dependency Inversion

Single Responsibility: Test

Data - What does know? - Relations between objects?Behavior - What problems resolve? - Services?

Open/Closed: Test

- No need to change working code

Liskov Substitution: Test

- Tests can use to check the heirs instead ancestors- In case of violation of unit tests are complicated

Interface Segregation: Test

- Tests help to split the interfaces- Mocks dictates API

Dependency Inversion:TDD

- Service Locator or Dependency Injection?- Mocks in TDD create abstractions- Setting tests easier with Dependency Injection

TDD +/-- Confidence in the code to run- No code to Thrash- New solutions approves more quickly- New lever of your skills

- Slow refactoring- Tests are difficult - Doesn't work everywhere- Tests refactoring- TDD for bad smells code

FAQ...

- How many tests must be written?- TDD for existing projects- Must read

Books...

- Kent Beck "Test Driven Development By Example"

- Martin Fowler "Refactoring: Improving the Design of Existing Code"

- Joshua Kerievsky "Refactoring To Patterns"

- Michael Feathers "Working Effectively with Legacy Code"

Questions?