Unit Testing in Android

Step by Step

Created by Wig Cheng (鄭元誠) and Chang Yu-heng (張昱珩)

2014-07-07

Software Development Process

The V-Model

Coding　　Unit Test

=> Test-driven development (TDD)

Unit Testing

An unit can be viewed as the smallest testable part of an application

An entire interface or an individual method in object-oriented programming
An entire module or an individual function/procedure in procedural programming

Production Code

Test Code

public int sum(int x, int y) {
return x + y;
}

public void testSum() {
int i = sum(1, 2);
assertEquals(i, 3);
}

Testing Methods

White-box testing

The testing code is dedicated for the implementation

Pros:

Good coverage and implementation checking

Cons:

High cost

Black-box testing

The testing code is dedicated for the interface

Pros:

Good for interface checking

Grey-box testing

Basic Code Coverage Criteria

Function coverage
Statement coverage
Branch coverage
Condition coverage

Branch Coverage

Production Code

Test Code

public int max(int x, int y) {
  if (x > y)
    return x;
  else
    return y;
}

public void testMax() {
  int i = max(2, 1);
  assertEquals(i, 2);
  i = max(6, 9);
  assertEquals(i, 99);
}

Building an Unit Testing Environment

Software Requirement

JDK
Android SDK
Android Studio (IDE)
Genymotion (emulator)

Writing Test Cases

Testing Tools

Robolectric

Wouldn’t it be nice to run your Android tests directly from inside your IDE?

uiautomator

Automated functional UI test cases

MonkeyTalk

Capture and replay the test cases