Why TDD is relevant in mobile development and how to start adopting it today.

1. Fearless Coding
with Test Driven Development

2. Untested code is broken code
Martin Aspeli, Philipp von Weitershausen,
Plone Community

3. Test Driven Development

4. •1. Write a Failing test
•2. Implement the feature
•3. Refactor

5. •Write new code only if an
automated test has failed
•Eliminate duplication
Test Driven Development: by example
Kent Beck

6. coverage

7. it depends

8. Let’s go 100%

9. Asymptotic Coverage

10. Fearless Adoption
of Test Driven Development
ASYMPTOTIC

11. •5 Levels of Adoption
•Process
•Roles
•Costs & Benefits
•Adoption Framework

12. •youngling | level 1
!12

14. Story 2: User Login As a anonymous user, I want to
login with my email and
password so I can get a greeting
phrase.

15. Acceptance Criteria 2.1. User Logged In
2.2. Invalid password
2.3. Invalid email
2.4. Network Error
2.5. Server Error
!15

16. 2.1. User Logged In
Given the app is showing initial screen
When the user enters a registered email, the right
password and taps on login
Then the app shows greeting screen (user story 3)
!16

17. •youngling | REQUERIMENTS
ACCEPTANCE CRITERIA

18. •youngling | REQUERIMENTS
ACCEPTANCE CRITERIA
Keep it updated

19. •padawan | level 2

20. 2.1. User Logged In
Given the app is showing initial screen
When the user enters a registered email, the right
password and taps on login
Then the app shows greeting screen (user story 3)

30. Pending Refactor to Improve UI
Refactor to Improve Code
Add API Call

31. E2E Test A broad-stack test is a test that
exercises most of the parts of a
large application. It's often
referred to as an end-to-end
test or full-stack test or UI Test.
Broad Stack Test
Martin Fowler

32. Keep it simple, adoption is the goal
UI need to wait ?, use Thread.sleep(5000)

33. •padawan |
E2E TESTING
DECOUPLING IMPROVEMENT
PENDING IMPROVEMENTS

34. •knight | level 3

35. USER INTERFACE
BUSINESS LOGIC
SERVER
TEST

36. USER INTERFACE
BUSINESS LOGIC
STUB
TEST

39. •knight | HERMETIC ENVIRONMENT
NEW TOOLS, ANDROID FLAVORS

40. •master | level 4

41. 2.1. User Logged In
Given the app is showing initial screen
When the user enters a registered email, the right
password and taps on login
Then the app shows greeting screen (user story 3)

42. LoginActivity
2.1. User Logged In
InputValidator LoginViewModel LoginRepository

44. Unit Test involves the testing of individual
units (classes) to demonstrate
that the program executes as per
the specification and that it
validates the design and
technical quality of that
particular unit.
Component Test
Martin Fowler

45. Tools Upgrade Stubs Mocks
Service Locator Dependency Injection

46. •master | UNIT TESTING
TOOLS UPGRADE

47. •grand master | level 5

48. 100%

49. Start by Unit, then go to E2E

50. Roles
In a Fearless Adoption of TDD

51. Analyst Developer QA
Level 1 O
Level 2-5 O
Run Tests O O

52. Analyst Developer QA
TDD
Champion
Level 1 O
Level 2-5 O
Run Tests O O
Assess &
Measure
O

53. TDD Champion One per team, project, company
Set and review test strategy
Goals Setting
TDD adoption and level assessment
Code Coverage measuring
Cost and benefits measuring

54. Start now

55. 1. Own the process
2. Define goals, scope and a timeframe
3. Assign roles
4. Execute
5. Measure
6. Improve
Start TDD Today

56. two more things…

57. 1. Test Compatible Architecture
2. Cloud Testing
3. Free regression Test
TDD Benefits

58. Tools
https://github.com/wix/detox

59. THANK YOU
Roberto Allende | @robertoallende
Paperkite LTD | @paperkiteltd
read more
https://tinyurl.com/TDDMobileRefresh

60. Fearless Girl Statue - Anthony Quintano
https://www.flickr.com/photos/quintanomedia/33736548216/
https://creativecommons.org/licenses/by/2.0/
Gray Box End-to-End Testing and Automation Framework for Mobile Apps
https://github.com/wix/detox
Plone Community - Roberto Allende
https://www.flickr.com/photos/r0ver/1544661972/in/album-72157602358623481/
Asymptotic behavior of the zeros of the digamma function
Maths Exchange
https://math.stackexchange.com/questions/1200325/asymptotic-behavior-of-the-
zeros-of-the-digamma-functionhttps://math.stackexchange.com/questions/1200325/
asymptotic-behavior-of-the-zeros-of-the-digamma-function
Image Credits