Testing on Android

copyright © 2009 cod technologies ltd www.codtech.com

droidcon 2009testing on android

diego torres [email protected]

london, december 2009


“Never test the depth of the water with both feet.”

Anonymous


agenda

● test driven development

● behavior driven development

● building blocks

● your first tdd android application

● writing tests


resources

● http://android.codtech.com/droidcon2009


after this section you will

● understand test driven development

● be introduced to behavior driven development

● recognize test building blocks

after this section you will...


what is test driven development ?

TDD is the strategy of starting the development

process by the test cases and then provide the software that

satisfies these tests


test driven development

uml activity diagram


kinds of automated tests● unit tests

– written by programmers

– for programmers

– in a programming language

● functional or acceptance tests

– written by business people and QA

– for business people

– in a high level language

check FitNesse www.fitnesse.org


behavior driven development● evolution in the thinking behind TDD● common vocabulary between business and

technology● framework of activity based on three principles

– business and technology should refer to the same system in the same way

– any system should have an identified, verifiable value to the business

– upfront analysis, design and planning all have a diminishing return http://behaviourdriven.org

http://jbehave.org

http://behaviour-driven.org/


scenario● text scenario

● defining steps

Given I am not logged inWhen I log in as Liz with a password JBehaverThen I should see a message, "Welcome, Liz!"

@Given("I am not logged in") public void logOut() { currentPage.click("logout"); }


testing on android● android platform integrates a

testing framework● it's based on Junit 3● supports

– unit tests– functional tests– activity tests– mock objects– utilities to simplify test

creationPortions of this page are reproduced from work created and shared by

Google and used according to terms described in the Creative Commons 2.5 Attribution License.


is this all the documentation ?

a framework for writing android test cases and

suites. (?)


ActivityInstrumentationTestCase2● functional testing of single Activity● Activity created used system infrastructure● Activity can be manipulated● Tests can be annotated with @UiThreadTest● Intents can be injected with setActivityIntent()

● sendKeys() can be used to simulate user interaction


uml class diagram


ApplicationTestCase● test Application in controlled environment● basic lyfecycle support

– onCreate() called after createApplication()– tearDown() calls onDestroy()

● mock Context can be injected● Application can be terminated with

terminateApplication()


ActivityUnitTestCase● isolated testing of a single Activity● Activity created with minimal connection to the

system● mocked dependencies can be injected● Activity will not participate in the normal

interactions with the system● some methods should be avoided and will throw

exceptions if called


ProviderTestCase2<T>● isolated testing of a ContentProvider● uses a MockContentResolver to

– access the provider– restricts access to filesystem (db & files)– injects IsolatedContext

● environment managed by setUp() and tearDown()


ServiceTestCase<T>● framework to test Services● basic support for lifecycle

– onCreate() called after startService(Intent) or bindService(Intent)

– depending on how was started tearDown() calls appropriate method

● mock objects can be injected by– setApplication()– setContext()


AndroidTestCase● base class that can be extended to support

different requirements● use this if you need

– isolate components– test custom Views– test permissions– access Resources


ViewAsserts● useful assertions about Views

– Views are aligned in several ways– ViewGroups contain Views– View is on screen– View has specific screen coordinates


TouchUtils● use these methods to generate touch events● clickView() to simulate touching● drag...() to touch and drag● longClick() for touching and holding● scroll...() to simulate different scrolling● tapView() to touch and release quickly


android.test.mockall classes has nonfunctional methods● MockApplication● MockContentResolver● MockContext● MockDialogInterface● MockPackageManager● MockResources


“You know you've achieved perfection in design, not when you have nothing more to add, but when you have nothing more to take away.”

Antoine de SaintExupery


after this section you will

● be able to create a project and its corresponding tests project

● apply test driven development techniques

● get acquainted with android tests

after this section you will...


design

we leave space for keyboard

if there's and error should be

displayed here (O)

converts temperatures

from celsius to

fahrenheit and

vice-versawhen th

e user

enters a

temperature in

one

field the other

is

updated

automatically


create project

Choose the build target


create test project

always create a test project

other values are automatically

selected


create test case

to create the test for the Activity we use ActivityInstrumentationTestCase2<T>

the Activity as the class under test

create method stubs


check generated test case/** * Copyright © 2009 COD Technologies Ltd. All rights reserved. */package com.codtech.android.training.tctdd1.test;

import android.test.ActivityInstrumentationTestCase2;

import com.codtech.android.training.tctdd1.TemperatureConverterActivity;

public class TemperatureConverterActivityTests extendsActivityInstrumentationTestCase2<TemperatureConverterActivity> {

/** * @param name */public TemperatureConverterActivityTests(String name) {

super("com.codtech.android.training.tctdd1",TemperatureConverterActivity.class);

setName(name);}

// setUp() and tearDown() not showed}

adjust stub constructor to pass required arguments

to super


setUp

/* (non-Javadoc) * @see android.test.ActivityInstrumentationTestCase2#setUp() */protected void setUp() throws Exception {

super.setUp();

final TemperatureConverterActivity activity = getActivity();

celsius = (EditText)activity.findViewById(com.codtech.android.training.tctdd1.R.id.celsius);

fahrenheit = (EditText)activity.findViewById(com.codtech.android.training.tctdd1.R.id.fahrenheit);

}

these constants are not yet created, we

need to add the Views and Ids to the

layout

create fields when necessary


layout

Ids should satisfy

previous requirements


add some UI tests@SmallTestpublic void testSimpleCreate() {

assertNotNull(getActivity());

assertNotNull(celsius);assertNotNull(fahrenheit);

ViewAsserts.assertOnScreen(fahrenheit.getRootView(), celsius);ViewAsserts.assertOnScreen(celsius.getRootView(), fahrenheit);

}

@SmallTestpublic void testAlignment() {

ViewAsserts.assertRightAligned(celsius, fahrenheit);ViewAsserts.assertLeftAligned(celsius, fahrenheit);

}

@SmallTestpublic void testFiledsStartEmpty() {

assertTrue("Celsius field starts not empty", "".equals(celsius.getText().toString()));

assertTrue("Fahrenheit field starts not empty", "".equals(fahrenheit.getText().toString()));

}


now some functional tests

@UiThreadTestpublic void testFahrenheitToCelsiusConversion() {

celsius.clear(); fahrenheit.clear();

final double f = 32.5;fahrenheit.requestFocus();fahrenheit.setNumber(f);celsius.requestFocus();final double c = TemperatureConverter.fahrenheitToCelsius(f);final double cr = celsius.getNumber();final double delta = Math.abs(c - cr);final String msg = "" + f + "F should be " + c + "C but was " +

cr + " (delta " + delta + ")";assertTrue(msg, delta < 0.005);

}

we don't have a class implementing

setNumber(), getNumber() and

clear() so we will be creating it soon

we don't have a TemperatureConverter

either

we run the test in the UI thread


and more tests

@SmallTestpublic void testCelsiusToFahrenheitConversion() {

final double c = -105.35;TouchUtils.tapView(this, celsius);sendKeys("MINUS 1 0 5 PERIOD 3 5");final double cr = celsius.getNumber();assertEquals("Send keys should have set " + c + " but set " +

cr, c, cr);final double f = TemperatureConverter.celsiusToFahrenheit(c);final double fr = fahrenheit.getNumber();final double delta = Math.abs(f - fr);final String msg = "" + c + "C should be " + f + "F but was " +

fr + " (delta " + delta + ")";assertTrue(msg, delta < 0.005);

}

create method stub in TemperatureConverter

don't run this test in UI thread


create EditNumber class

extend EditText

create a new

package for views

once we create EditNumber we should refactor our main layout

and fields


create TemperatureConverter class


create a TestCase

test TemperatureConverter

create stubs


select methods to test


complete actual tests

public void testFahrenheitToCelsius() {for (double c: conversionTableDouble.keySet()) {

final double f = conversionTableDouble.get(c); final double cr = TemperatureConverter.fahrenheitToCelsius(f); final double delta = Math.abs(c - cr); final String msg = "" + f + "F should be " + c + "C but is " +

cr + " (delta " + delta + ")"; assertTrue(msg, delta < 0.0001);

}}

public void testCelsiusToFahrenheit() {for (double c: conversionTableDouble.keySet()) {

final double f = conversionTableDouble.get(c); final double fr = TemperatureConverter.celsiusToFahrenheit(c); final double delta = Math.abs(f - fr); final String msg = "" + c + "C should be " + f + "F but is " +

fr + " (delta " + delta + ")" ; assertTrue(msg, delta < 0.0001); }}


test exceptionspublic void testAbsoluteZeroCelsius() {

Exception e = null;

try {TemperatureConverter.celsiusToFahrenheit(-274);

}catch (RuntimeException re) {

}

assertNotNull("Absolute zero C not detected", e);}

public void testAbsoluteZeroFahrenheit() {Exception e = null;

try {TemperatureConverter.fahrenheitToCelsius(-460);

}catch (RuntimeException re) {

e = re;}

assertNotNull("Absolute zero F not detected", e);}


conversion table

private static final HashMap<Double, Double> conversionTableDouble =new HashMap<Double, Double>();

static {// initialize (c, f) pairsconversionTableDouble.put(0.0, 32.0);conversionTableDouble.put(100.0, 212.0);conversionTableDouble.put(-1.0, 30.20);conversionTableDouble.put(-100.0, -148.0);conversionTableDouble.put(32.0, 89.60);conversionTableDouble.put(-40.0, -40.0);conversionTableDouble.put(-273.0, -459.40);

}

● simple conversion table to run several tests


run tests

conversion tests fail because we haven't implemented it yet


TemperatureConverterpackage com.codtech.android.training.tctdd1;

public class TemperatureConverter {

public static final double ABSOLUTE_ZERO_C = -273.0d;public static final double ABSOLUTE_ZERO_F = -459.4d;

private static final String ERROR_MESSAGE_BELOW_ZERO_FMT ="Invalid temperature: %.2f%c below absolute zero";

public static double celsiusToFahrenheit(double c) {if (c < ABSOLUTE_ZERO_C) {

throw new RuntimeException(String.format(ERROR_MESSAGE_BELOW_ZERO_FMT, c, 'C'));

}return (c * 1.8d + 32);

}

public static double fahrenheitToCelsius(double f) {if (f < ABSOLUTE_ZERO_F) {

throw new RuntimeException(String.format(ERROR_MESSAGE_BELOW_ZERO_FMT, f, 'F'));

}return ((f - 32) / 1.8d);

}}


run tests

tests fail now because we are doing the conversion right but we are invoking

empty methods in EditNumber that don't

update the ui

conversion tests succeded


implement EditNumber methodspackage com.codtech.android.training.tctdd1.view;

import android.content.Context;import android.util.AttributeSet;import android.widget.EditText;

public class EditNumber extends EditText {

public EditNumber(Context context) {super(context);

}

public EditNumber(Context context, AttributeSet attrs) {super(context, attrs);

}

public void clear() {setText("");

}

public void setNumber(double f) {setText(Double.toString(f));

}

public double getNumber() {return Double.valueOf(getText().toString());

}}

convenience methods delegating to EditText


run tests

a NumberFormatException because we are not changing

the other field when some new temperature is entered and thus the field is empty


onCreate/** Called when the activity is first created. */

@SuppressWarnings("unchecked")@Override

public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); celsius = (EditNumber)findViewById(R.id.celsius); fahrenheit = (EditNumber)findViewById(R.id.fahrenheit);

try { Class[] args = new Class[] { double.class }; celsius.addTextChangedListener(

new TemperatureChangedWatcher(fahrenheit, TemperatureConverter.class.getMethod(

"celsiusToFahrenheit", args))); fahrenheit.addTextChangedListener(

new TemperatureChangedWatcher(celsius,TemperatureConverter.class.getMethod(

"fahrenheitToCelsius", args))); } catch (Exception e) { // TODO Auto-generated catch block e.printStackTrace(); } }

add change listener to these fields


TemperatureChangedWatcherprivate static class TemperatureChangedWatcher implements TextWatcher {

private EditNumber dest;private Method convert;

public TemperatureChangedWatcher(EditNumber dest, Method convert) {this.dest = dest; this.convert = convert;

}

@Overridepublic void afterTextChanged(Editable s) {}

@Overridepublic void beforeTextChanged(CharSequence s, int start, int count,

int after) {}

@Overridepublic void onTextChanged(CharSequence s, int start, int before,

int count) {

if (!dest.hasWindowFocus() || dest.hasFocus() || s == null ) {return;

}// continued ...


TemperatureChangedWatcher

final String ss = s.toString();if ( "".equals(ss) ) {

dest.clear();return;

}

try {final double result = (Double)

convert.invoke(TemperatureConverter.class,Double.parseDouble(ss));

// display only 2 decimalsdest.setNumber(Math.rint(result*100)/100);

} catch (NumberFormatException e) {// WARNING// this is generated while a number is entered,// for example just a -' so we don't want to show the error

} catch (Exception e) {dest.setError(e.getCause().getLocalizedMessage());

}}

}


tests succeed


temperature converter

we leave space for keyboard

if there's and error should be

displayed here (O)

converts temperatures

from celsius to

fahrenheit and

vice-versawhen th

e user

enters a

temperature in

one

field the other

is

updated

automatically


instrumentation● Dev Tools Instrumentation TCTDD1 Tests→ →


eclipse● TCTDD1Test Run As Android JUnit Test→ →


command line

diego@bruce:\~$ adb -e shell am instrument -w -e class com.codtech.android.training.tctdd1.test.TemperatureConverterActivityTests com.codtech.android.training.tctdd1.test/android.test.InstrumentationTestRunner

com.codtech.android.training.tctdd1.test.TemperatureConverterActivityTests:.....Test results for InstrumentationTestRunner=.....Time: 5.564

OK (5 tests)


EditNumberTests

AndroidTestCase


select methods to test


constructor and setUp

/** * @param name */public EditNumberTests(String name) {

super();setName(name);

}

/* (non-Javadoc) * @see android.test.AndroidTestCase#setUp() */protected void setUp() throws Exception {

super.setUp();mockContext = new IsolatedContext(new MockContentResolver(),

getContext());editNumber = new EditNumber(mockContext);editNumber.setFocusable(true);

}

creating a mock context


complete actual tests/** * Test method for EditNumber#EditNumber(android.content.Context) */public void testEditNumberContext() {

assertNotNull(new EditNumber(mockContext));}

/** * Test method for EditNumber#EditNumber(Context, AttributeSet) */public void testEditNumberContextAttributeSet() {

// TODO// use a real AttributeSet for this test not nullassertNotNull(new EditNumber(mockContext, null));

}

/** * Test method for EditNumber#clear() */public void testClear() {

editNumber.setText("1234");editNumber.clear();assertEquals("editNumber should have been cleared",

"", editNumber.getText().toString());}


complete actual tests

public void testSetNumber() {final double d = 1.23d;editNumber.setNumber(d);final double dr = editNumber.getNumber();final String msg = "editNumber should be " + d + " but is " + dr;assertEquals(msg, d, dr);

}

public void testGetNumber() {final double d = 0.98d;final String ds = Double.toString(d);editNumber.setText(ds);final double dr = editNumber.getNumber();final String msg = "editNumber should be " + ds + " but is " + dr;assertEquals(msg, d, dr);

}


input testpublic class TemperatureConverterActivityTests extends

ActivityInstrumentationTestCase2<TemperatureConverterActivity> {

// …

@SmallTestpublic void testInputFilter() {

TouchUtils.tapView(this, celsius);final Double n = -1.234d;sendKeys("MINUS 1 PERIOD 2 PERIOD 3 PERIOD 4");Object nr = null;try {

nr = celsius.getNumber();}catch (NumberFormatException e) {

nr = celsius.getText();}

final String msg = "-1.2.3.4 should be filtered to " + n +" but is " + nr;

assertEquals(msg, n, nr);}

}


input filter

public class EditNumber extends EditText {

// …

/** * Initialization. * Set filter. * */private void init() {

// DigistKeyListener.getInstance(true, true) returns an// instance that accepts digits, sign and decimal pointfinal InputFilter[] filters = new InputFilter[]

{ DigitsKeyListener.getInstance(true, true) };

setFilters(filters);}

}

invoke init() from constructors


resources

● http://dtmilano.blogspot.com

● http://easymock.org

● http://code.google.com/p/hamcrest (matchers)

● http://mockito.org/

● http://developer.android.com/guide/developing/tools/monkey.html (ui exerciser)

● http://ricston.com/ricstontrainingforandroid/

● http://android.codtech.com


“If things seem under control, you're not going fast enough.”

Mario Andretti


thank youtesting on android

diego torres [email protected]

london, december 2009

Technology

Testing on Android