1.
CYA:
Cover Your App
Jorge D. Ortiz Fuentes
@jdortiz

2.
A Canonical
Examples
Production

3.
#AdvArchMobile
Agenda
★ Motivation
★ Facts
★ What’s missing?
★ Architecture
★ Live Coding
★ Recap

4.
Motivation

5.
But my code is
always awesome!

6.
#AdvArchMobile
Selfish Unit Tests
★ No more discussions
★ No more explanations to the team
★ No more questions
★ No more bugs introduced by them
★ No more missed deadlines
★ No more late hours

7.
#AdvArchMobile
Selfish Unit Tests
★ Prove (to others) instead of (your) intuition
★ No more explanations to the team
★ No more questions
★ No more bugs introduced by them
★ No more missed deadlines
★ No more late hours

8.
#AdvArchMobile
Selfish Unit Tests
★ Prove (to others) instead of (your) intuition
★ Define contract and assumptions
★ No more questions
★ No more bugs introduced by them
★ No more missed deadlines
★ No more late hours

9.
#AdvArchMobile
Selfish Unit Tests
★ Prove (to others) instead of (your) intuition
★ Define contract and assumptions
★ Document the code
★ No more bugs introduced by them
★ No more missed deadlines
★ No more late hours

10.
#AdvArchMobile
Selfish Unit Tests
★ Prove (to others) instead of (your) intuition
★ Define contract and assumptions
★ Document the code
★ Easier refactoring or change
★ No more missed deadlines
★ No more late hours

11.
#AdvArchMobile
Selfish Unit Tests
★ Prove (to others) instead of (your) intuition
★ Define contract and assumptions
★ Document the code
★ Easier refactoring or change
★ Better estimations for tests than debug
★ No more late hours

12.
#AdvArchMobile
Selfish Unit Tests
★ Prove (to others) instead of (your) intuition
★ Define contract and assumptions
★ Document the code
★ Easier refactoring or change
★ Better estimations for tests than debug
★ Reusable code = code + tests

13.
Prove correctness of
different aspects of
the public interface

14.
Test the parts that
you aren’t
developing now

15.
Facts

16.
Coverage
=
Measurement

17.
We want:
“Code is proven
correct in all cases”

18.
We get:
“Lines used by the
tests”

19.
Demo:
Demystifying
Coverage

20.
#AdvArchMobile
What you have seen
★ Full CRUD
★ 100% Kotlin (everything but generated
code)
★ Mockito + Mockito-Kotlin
★ Good architecture
★ TDD

21.
What is
Missing?

22.
#AdvArchMobile
Not Covered
★ Dagger factories
★ Platform: implementation details (activities,
adapters, application subclass, DI)

23.
Let’s do better

24.
Architecture

25.
MVP
ViewPresenterModel
display commands
events
fetch/change
data

26.
Test View Methods
ViewPresenterModel
display commands
events
fetch/change
data

27.
Test Events To Presenter
ViewPresenterModel
display commands
events
fetch/change
data
Presenter

28.
#AdvArchMobile
How to Mock the
Presenter
★ App uses Dagger 2 for DI
★ Dagger 2 is NOT meant for Unit Testing
★ Activities use Service Locator for DI
★ Service Locator abstraction is implemented
by Application subclass
★ Unit tests use another Application subclass

29.
And if I am an
MVVM Person?

30.
Live Coding

31.
Let’s write this
together

32.
#AdvArchMobile
Recap
★ Unit Tests are good for you (and for others)
★ Code coverage is not the best metric
★ Good coverage is better
★ A good architecture will help to cover the
different aspects of your

33.
Thank
You!

34.
@jdortiz
#AdvArchMobile