pdk/docs/guide/instrumentation_testing.jd

page.title=Instrumentation Testing
pdk.version=1.0
doc.type=guide
@jd:body

<div id="qv-wrapper">
<div id="qv">
<h2>In this document</h2>
<a name="toc"/>
<ul>
<li><a href="#androidInstrumentationTestingFramework">Instrumentation Framework</a></li>
<li><a href="#androidInstrumentationFrameworkPlatform">Platform Test Suites</a></li>
<li><a href="#androidInstrumentationFrameworkWritingRunning">Running Tests</a></li>
<li><a href="#androidInstrumentationTestingCreating">Writing Tests</a></li>
<li><a href="#troubleshooting">Troubleshooting</a></li>
</ul>
</div>
</div>

<p>This document describes how to use the Instrumentation Framework to write test cases. Instrumentation testing allows you to verify a particular feature or behavior with an automated JUnit TestCase. You can launch activities and providers within an application, send key events, and make assertions about various UI elements. </p>
<p>You should have a working knowledge of the following:</p>
<ul>
  <li> Android Application Framework</li>
  <li> Using <code>adb</code>, <code>am</code> and various logging functionality </li>
  <li> A brief understanding of the application of interest, that is, the names of the classes which handle the intents etc. </li>
  <li> JUnit testing.</li>
</ul>
<p> Each Android application runs in its own process. Instrumentation kills the application process and  restarts the process with Instrumentation. Instrumentation gives a handle to the application context used to poke around the application to validate test assertions, allowing you to write test cases to test applications at a much lower level than UI screen shot tests. Note that Instrumentation cannot catch UI bugs. </p>


<a name="androidInstrumentationTestingFramework"></a><h3>Instrumentation Framework</h3>



<a name="androidInstrumentationTestingClasses"></a><h4>Classes</h4>

<p> The following classes help glue together <code>Instrumentation</code> with JUnit testing. </p>
<table>
  <tr>
    <th scope="col">Class</th>
    <th scope="col">Description</th></tr>
  <tr>
    <td valign="top"><code>InstrumentationTestCase</code></td>
    <td valign="top">
	<p>This extends the standard JUnit <code>TestCase</code> and offers access to an <code>Instrumentation</code> class. Write tests inside your instrumentation class any way you see fit. For example, your test might launch activities and send key events. For this to work properly, the instrumentation needs to be injected into the test case.</p>	</td>
  </tr>
  <tr>
    <td valign="top"><code>InstrumentationTestRunner</code></td>
    <td valign="top">The instrumentation test runner is an instrumentation that runs instrumentation test cases and injects itself into each test case. Instrumentation test cases need to be grouped together with an instrumentation test runner with the appropriate target package.</td>
  </tr>
  <tr>
    <td valign="top"><code>InstrumentationTestSuite</code></td>
    <td valign="top">The instrumentation test suite is a simple extension of the standard JUnit <code>TestSuite</code> that keeps a member <code>Instrumentation</code> variable on hand to inject into each <code>TestCase</code> before running them.  It is used by <code>InstrumentationTestRunner</code>.</td>
  </tr>
</table>
<p> Three additional base classes extend <code>InstrumentationTestCase</code> to allow you to test <code>Activity</code> and <code>Provider</code> classes:</p>
<table>
  <tr>
    <th scope="col">Class</th>
    <th scope="col">Description</th>
  </tr>
  <tr>
    <td valign="top"><code>ActivityTestCase</code></td>
    <td valign="top"><p>This class can be used to write tests for a specific activity.  An activity is launched in its <code>setUp()</code> method and finished with <code>tearDown</code>.  If you write a test case that extends <code>ActivityTestCase</code>, you can write tests that access the activity using <code>getActivity()</code> and assume it has been set up properly.</p></td>
  </tr>
  <tr>
    <td valign="top"><code>ServiceTestCase</code></td>
    <td valign="top">This test case provides a framework in which you can test Service classes in a controlled environment.  It provides basic support for the lifecycle of a Service, and hooks by which you can inject various dependencies and control the environment in which your Service is tested.</td>
  </tr>
  <tr>
    <td valign="top"><code>SingleLaunchActivityTestCase</code></td>
    <td valign="top">This class is similar to <code>ActivityTestCase</code> except that the activity is launched once per class instead of every time the test case calls setup. </td>
  </tr>
  <tr>
    <td valign="top"><code>ProviderTestCase</code></td>
    <td valign="top">This class is similar to <code>ActivityTestCase</code> except that it will setup, tear down, and provide access to the <code>Provider</code> of your choice.</td>
  </tr>
</table>


<a name="androidInstrumentationFrameworkamCommand"></a><h4>Understanding the am Command</h4>

<p>The am command is a command-line interface to the ActivityManager (see <a href="http://code.google.com/android/reference/android/app/ActivityManager.html">http://code.google.com/android/reference/android/app/ActivityManager.html</a> for details). <code>am</code> is used to start and instrument activities using the adb shell command, as shown in the snippet below:</p>
<pre class="prettify">
&gt; adb shell am
usage: am [start|instrument]
       am start [-a &lt;ACTION&gt;] [-d &lt;DATA_URI&gt;] [-t &lt;MIME_TYPE&gt;]
                [-c &lt;CATEGORY&gt; [-c &lt;CATEGORY&gt;] ...]
                [-e &lt;EXTRA_KEY&gt; &lt;EXTRA_VALUE&gt; [-e &lt;EXTRA_KEY&gt; &lt;EXTRA_VALUE&gt; ...]
                [-n &lt;COMPONENT&gt;] [-D] [&lt;URI&gt;]
       am instrument [-e &lt;ARG_NAME&gt; &lt;ARG_VALUE&gt;] [-p &lt;PROF_FILE&gt;]
                [-w] &lt;COMPONENT&gt;
For example, to start the Contacts application you can use
&gt; adb shell am start -n com.google.android.contacts/.ContactsActivity
</pre>


<a name="androidInstrumentationFrameworkPlatform"></a><h3>Platform Test Suites</h3>

<p>This section provides an overview for various unit and functional test cases that can be executed through the instrumentation framework.</p>


<a name="androidTestingPlatformFramework"></a><h4>Framework Tests</h4>

<p>Framework test cases test the Android application framework or specific Android application functionality that requires an Android runtime context.  These tests can be found in <code>//device/tests</code> and <code>//device/apps/AndroidTests</code>.</p>


<a name="androidTestingPlatformCoreLibrary"></a><h4>Core Library</h4>

<p>Core library test cases test the Android library functionality that does not require an Android runtime context.  These tests are split into Android library (android.* package space) tests at <code>//device/java/tests</code> and Java library (java.*, javax.*, etc. packages) tests at <code>//device/dalvik/libcore/.../tests</code>.</p>


<a name="androidInstrumentationFrameworkWritingRunning"></a><h3>Running Tests</h3>

<p>Each instrumentation test case is similar to an Android application with the distinction that it starts another application. For example, have a look in the <code>tests/Contacts</code> directory. </p>
<ul>
  <li> There should be a Makefile and an Android Manifest file. </li>
  <li> Tests are located in <code>tests/Contacts/src/com/google/android/contactstests</code>. </li>
  <li> The Instrumentation Test Runner is located at <code>tests/Contacts/src/com/google/android/contactstests/functional/ContactsInstrumentationTestRunner.java</code>.</li>
</ul>
<p>Suppose you have a makefile with <code>Contactstests</code> as the target. </p>
<ul>
  <li> <code>make Contactstests</code>: Compiles the test cases. </li>
  <li> <code>adb install Contactstests.apk</code>: Installs the apk on the device. </li>
  <li> Use the adb shell <code>am</code> command to run them. </li>
</ul>
<p> To run your tests, use the <code>am instrument</code> command with your <code>InstrumentationTestRunner</code> as its argument. Results are printed as a result of the instrumentation. For example, the following snippet displays the output after running the framework tests with one test failing (note the unusual syntax caused by how instrumentations are run via <code>am</code>):</p>
<pre class="prettify">
$ adb shell am instrument -w com.google.android.frameworktest/.tests.FrameworkInstrumentationTestRunner
INSTRUMENTATION_RESULT: test results:=.......F.......
Time: 6.837
There was 1 failure:
1) testSetUpConditions(com.google.android.frameworktest.tests.focus.RequestFocusTest)junit.framework.AssertionFailedError: requestFocus() should work from onCreate.
        at com.google.android.frameworktest.tests.focus.RequestFocusTest.testSetUpConditions(RequestFocusTest.java:66)
        at java.lang.reflect.Method.invokeNative(Native Method)
        at android.test.InstrumentationTestSuite.runTest(InstrumentationTestSuite.java:73)
        at android.test.InstrumentationTestSuite.runTest(InstrumentationTestSuite.java:73)
        at android.test.InstrumentationTestRunner.onStart(InstrumentationTestRunner.java:151)
        at android.app.Instrumentation$InstrumentationThread.run(Instrumentation.java:1088)

FAILURES!!!
Tests run: 14,  Failures: 1,  Errors: 0

&lt;RETURN&gt; to continue

INSTRUMENTATION_CODE: -1
$ 
</pre>


<a name="androidInstrumentationTestingRunningAll"></a><h4>All Tests with Default TestRunner behavior</h4>

<p>If no class or package is passed in to run, InstrumentationTestRunner will automatically find and run all tests under the package of the test application (as defined by the <code>android:targetPackage</code> attribute of the instrumentation defined in its manifest file).
</p> 
<pre> 
$ adb shell am instrument -w \
  com.android.samples.tests/android.test.InstrumentationTestRunner
 
INSTRUMENTATION_RESULT: Test results for InstrumentationTestRunner=..........
Time: 2.317
 
OK (10 tests)
 
 
INSTRUMENTATION_CODE: -1
</pre>


<a name="androidTestingTestSinglePakcage"></a><h4>Running all Tests Under Single Package</h4>

<p>If you have many tests under one package, use the <code>-e package &lt;packagename&gt;</code> option to run all tests under that package without having to manually create a test suite.</p> 
<pre> 
$ adb shell am instrument -w \
  -e package com.android.samples.view \
  com.android.samples.tests/android.test.InstrumentationTestRunner
INSTRUMENTATION_RESULT: Test results for InstrumentationTestRunner=........
Time: 1.587
 
OK (8 tests)
</pre>  


<a name="androidTestingSingleTestSuite"></a><h4>Running a Single Test Suite</h4>

<p>If you prefer to explicitly state which tests comprise all of your tests, you can define a test suite and run that directly. By convention, all test packages in your system should have at least one suite called <code>AllTests</code> (see <code>AllTests.java</code>).  To run all of the tests using the <code>AllTests</code> suite for the api demos test app:</p>

<pre> 
$ adb shell am instrument -w \
  -e class com.android.samples.AllTests \
  com.android.samples.tests/android.test.InstrumentationTestRunner
 
INSTRUMENTATION_RESULT: Test results for AllTests=..........
Time: 2.286
 
OK (10 tests)
 
 
INSTRUMENTATION_CODE: -1
</pre> 


<a name="androidInstrumentationTestingRunningSingleTestCase"></a><h4>A Single Test Case</h4>

<pre> 
$ adb shell am instrument -w \
  -e class com.android.samples.view.Focus2ActivityTest \
  com.android.samples.tests/android.test.InstrumentationTestRunner
 
INSTRUMENTATION_RESULT: Test results for Focus2ActivityTest=....
Time: 1.359
 
OK (4 tests)
 
 
INSTRUMENTATION_CODE: -1
</pre> 


<a name="androidInstrumentationTestingRunningSingleTest"></a><h4>A Single Test</h4>

<pre> 
$ adb shell am instrument -w \
  -e class com.android.samples.view.Focus2ActivityTest#testGoingLeftFromRightButtonGoesToCenter \
  com.android.samples.tests/android.test.InstrumentationTestRunner
 
INSTRUMENTATION_RESULT: Test results for Focus2ActivityTest=.
Time: 0.51
 
OK (1 test)
 
 
INSTRUMENTATION_CODE: -1
</pre> 


<a name="androidTestingDebugging"></a><h4>Attaching a debugger to your test</h4>

<p>In order to debug your test code, instruct the controller to stop and wait for the debugger by adding <code>-e debug true</code> to your
command line.  This causes the test runner to stop and wait for the debugger just before calling your <code>setUp()</code> method.  For example,</p> 

<pre> 
$ adb shell am instrument -w \
  -e debug true \
  com.android.samples.tests/android.test.InstrumentationTestRunner
</pre> 


<a name="androidInstrumentationTestingCreating"></a><h3>Writing Tests</h3>

<p>When writing tests, refer to the ApiDemos tests as models (located at <code>//device/samples/ApiDemos</code>). This section provides an overview of the test structure with ApiDemos.</p>


<a name="androidTestingLocationFiles"></a><h4>Location of Files</h4>

<p>Test packages should use the following structure and include <code>Android.mk</code>, <code>AndroidManifest.xml</code>, <code>AllTests.java</code>, and a src directory that mirrors the src directory of the tested application.</p> 
<p>Files are located within a <code>tests</code> directory found in the root directory:</p> 
<pre> 
$ find samples/ApiDemos/tests
samples/ApiDemos/tests
samples/ApiDemos/tests/Android.mk
samples/ApiDemos/tests/AndroidManifest.xml
samples/ApiDemos/tests/src
samples/ApiDemos/tests/src/com
samples/ApiDemos/tests/src/com/google
samples/ApiDemos/tests/src/com/google/android
samples/ApiDemos/tests/src/com/google/android/samples
samples/ApiDemos/tests/src/com/google/android/samples/AllTests.java
samples/ApiDemos/tests/src/com/google/android/samples/ApiDemosTest.java
samples/ApiDemos/tests/src/com/google/android/samples/os
samples/ApiDemos/tests/src/com/google/android/samples/os/MorseCodeConverterTest.java
samples/ApiDemos/tests/src/com/google/android/samples/view
samples/ApiDemos/tests/src/com/google/android/samples/view/Focus2ActivityTest.java
samples/ApiDemos/tests/src/com/google/android/samples/view/Focus2AndroidTest.java
</pre>


<a name="androidTestingContentMakefile"></a><h4>Contents of makefile</h4>

<p>The contents of the makefile are similar to a normal application with the addition of a <code>LOCAL_INSTRUMENTATION_FOR</code> declaration.<p /> 
<pre> 
# Add appropriate copyright banner here
LOCAL_PATH:= $(call my-dir)
include $(CLEAR_VARS)
 
# We only want this apk build for tests.
LOCAL_MODULE_TAGS := tests
 
# Include all test java files.
LOCAL_SRC_FILES := $(call all-java-files-under, src)
 
# Notice that we don't have to include the src files of ApiDemos because, by
# running the tests using an instrumentation targeting ApiDemos, we
# automatically get all of its classes loaded into our environment.
 
LOCAL_PACKAGE_NAME := ApiDemosTests
 
LOCAL_INSTRUMENTATION_FOR := ApiDemos
 
include $(BUILD_PACKAGE)
</pre>


<a name="androidTestingContentManifest"></a><h4>Content of Manifest</h4>

<p>Use the following example to create an <code>AndroidManifest.xml</code> file that declares the instrumentation. Specify that the framework supplied Instrumentation TestRunner targest the package of your application, allowing the tests that are run with the instrumentation to get access to all of the classes of your application without having to build the source into the test app. The name of the test application is typically the same as your target application with <code>.tests</code> appended. </p>
<pre> 
# Add appropriate copyright banner here
&lt;manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.android.samples.tests"&gt;
 
    &lt;uses-permission android:name="android.permission.RUN_INSTRUMENTATION" /&gt;
 
    &lt;!--
    This declares that this app uses the instrumentation test runner targeting
    the package of com.android.samples.  To run the tests use the command:
    "adb shell am instrument -w com.android.samples.tests/android.test.InstrumentationTestRunner"
    --&gt;
    &lt;instrumentation android:name="android.test.InstrumentationTestRunner"
                     android:targetPackage="com.android.samples"
                     android:label="Tests for Api Demos."/&gt;
 
&lt;/manifest&gt;
</pre> 
<p>&nbsp;</p> 
<p>The following snippet will prefix the <code>/android.test.InstrumentationTestRunner</code> when running tests from the command line:</p>
<pre> 
$ adb shell am instrument -w \
  com.android.samples.tests/android.test.InstrumentationTestRunner
</pre> 


<a name="androidInstrumentationTestingCreatingTestRunner"></a><h4>New Instrumentation TestRunner</h4>

<p>Create a class that derives from this class. You must override two abstract methods; one that returns the class loader of the target package, and another that defines all of the tests within the package. For example, the snippet below displays the test runner for the framework tests.</p>
<pre class="prettify">
public class FrameworkInstrumentationTestRunner extends InstrumentationTestRunner {

    @Override
    public TestSuite getAllTests() {
        InstrumentationTestSuite suite = new InstrumentationTestSuite(this);

        suite.addTestSuite(FocusAfterRemovalTest.class);
        suite.addTestSuite(RequestFocusTest.class);
        suite.addTestSuite(RequestRectangleVisibleTest.class);
        return suite;
    }

    @Override
    public ClassLoader getLoader() {
        return FrameworkInstrumentationTestRunner.class.getClassLoader();
    }
}
</pre>
<p> Next, in an appropriate <code>AndroidManifest.xml</code>, define the instrumentation for the derived class with the appropriate <code>android:targetPackage</code> set.  For example, the snippet below defines the instrumentation runner for the framework tests.</p>
<pre class="prettify">
&lt;uses-permission android:name="android.permission.RUN_INSTRUMENTATION" /&gt;

&lt;instrumentation android:name="android.tests.FrameworkInstrumentationTestRunner"
                 android:targetPackage="com.google.android.frameworktest"
                 android:label="framework instrumentation test runner" /&gt;
</pre>		


<a name="androidInstrumentationTestingCreatingTestCase"></a><h4>New InstrumentationTestCase</h4>

<p> To create a new test case, write a class that extends <code>InstrumentationTestCase</code> in the same application as your test runner.  The following snippet illustrates an example <code>ActivityTestCase</code> that tests an activity named <code>MyActivity</code>.</p>
<pre class="prettify">
public class ButtonPressTest extends ActivityTestCase&lt;MyActivity&gt; {

    Button mLeftButton;

    public ButtonPressTest() {
        super("com.example", MyActivity.class);
    }

    @Override
    public void setUp() throws Exception {
      super.setUp();
      mLeftButton = (Button) getActivity().findViewById(R.id.leftButton);
    }

    public void testFocusMovesToRight() throws Exception {
        assertTrue(mLeftButton.hasFocus());
        getInstrumentation().sendCharacterSync(KeyEvent.KEYCODE_DPAD_RIGHT);

        Button rightButton = (Button) getActivity().findViewById(R.id.rightButton);
        assertTrue(rightButton.hasFocus());
    }

    // could have several more tests...
}
</pre>


<a name="androidInstrumentationFrameworkTestCase"></a><h4>Exploring a Test Case</h4>

<p> The test case described in this section adds and tests a new Contact. Note that you can send intents, register intent receivers, etc. </p>
<p><code>Instrumentation.java</code> has helper functions that send key events and strings, for example: </p>
<ul>
  <li><code>getInstrumentation()</code>: Returns the handle to the instrumentation </li>
  <li><code>sendCharacterSync</code>: Sends a character. </li>
  <li><code>sendStringSync</code>: Sends a string to an input box. </li>
  <li><code>sendKeyDownUpSync</code>: Sends a specific keyevent. </li>
  <li><code>sendTrackballEventSync</code>: Sends a trackball event.</li>
</ul>
<p> You can find the test case below at <code>device/tests/Contacts.</code></p>
<pre class="prettify">
private void addNewContact(String name, int star, int phoneType, String number, String label,
		String email, int emailType){
	ContentValues values = new ContentValues();
	Uri phoneUri = null;
	Uri emailUri = null;

	values.put(Contacts.People.NAME, name);
	values.put(Contacts.People.STARRED, star);

	//Add Phone Numbers
	Uri uri = mActivity.getContentResolver().insert(Contacts.People.CONTENT_URI, values);
	phoneUri = Uri.withAppendedPath(uri, Contacts.People.Phones.CONTENT_DIRECTORY);

	values.clear();
	values.put(Contacts.Phones.TYPE, phoneType);
	values.put(Contacts.Phones.NUMBER, number);
	values.put(Contacts.Phones.LABEL, label);
	mActivity.getContentResolver().insert(phoneUri, values);

	//Add Email
	emailUri = Uri.withAppendedPath(uri, ContactMethods.CONTENT_DIRECTORY);

	values.clear();
	values.put(ContactMethods.KIND, Contacts.KIND_EMAIL);
	values.put(ContactMethods.DATA, email);
	values.put(ContactMethods.LABEL, "");
	values.put(ContactMethods.TYPE, emailType);
	mActivity.getContentResolver().insert(emailUri, values);
}


 public void testAddSaveSingleContact(){
	int previousCount = mActivity.getListView().getCount();
	String message;

	addNewContact(INPUT_NAME_1 + "1", "5435754532", "1" + INPUT_EMAIL_1, CONFIRM_OPTION);

	message = "Added 1 to initial length=" + previousCount + ", but resulted with a count=" +
		mActivity.getListView().getCount();
	assertEquals(message, ++previousCount, mActivity.getListView().getCount());

	// Check Content; Name; Num; Starred
	assertEquals(INPUT_NAME_1 + "1", getTextFromView(0, android.R.id.text1));
	assertEquals("5435754532", getTextFromView(0, android.R.id.text2));

	//Check email is saved
	//cursor = returnEmailCursorAtId("1");
	Uri uri = Uri.parse("content://contacts/people/1");
	uri = Uri.withAppendedPath(uri, ContactMethods.CONTENT_DIRECTORY);
	Cursor cursor = mActivity.getContentResolver().query(uri, CONTACTS_COLUMNS, null, null, null);
	assertTrue("returnEmailCursorAtId: Moving cursor to first row has failed", cursor.first());

	int dataIndex = cursor.getColumnIndexOrThrow("data");
	assertEquals("1" + INPUT_EMAIL_1, cursor.getString(dataIndex));
	cursor.deactivate();
}
	</pre>


<a name="androidTestingKindsofTests"></a><h4>Deciding Kinds of Tests to Write</h4>

<p>Once you are bootstrapped with your test application, you can start writing tests.  There are three of types of tests you may wish to write:</p> 
<p><ul> 
<li> <strong>TestCase</strong>: The standard junit test case.
</li> 
<li> <strong>AndroidTestCase</strong>: A test case with access to a Context object that is injected for you by the instrumentation test runner.
</li> 
<li> <strong>InstrumentationTestCase</strong>: A test case with access to an Instrumentation, which can be used to launch activities, content providers, send key events, etc.
</li> 
</ul> 
</p> 
<p>The API Demos test suite includes examples of all three styles and can be used as a guideline for writing each type of test.</p>
<p>There are two utility classes available for the most common uses of InstrumentationTestCase: ActivityTestCase and ProviderTestCase.  See their javadoc for more information.
</p>


<a name="troubleshooting"></a><h3>Troubleshooting</h3>

<p>If you run your test cases and nothing appears to happen, have a look at <code>adb logcat</code>. The following is a common problem:</p>
<pre class="prettify">
I/dalvikvm(  688): threadid=11: attached from native, name=Binder Thread #1
I/dalvikvm(  688): threadid=13: attached from native, name=Binder Thread #2
W/ActivityManager(  469): Unable to find instrumentation info for: ComponentInfo{com.google.android.browser_instrumentation/com.google.android.browser_instrumentation.BrowserWebkitLayoutInstrumentation}
D/AndroidRuntime(  688): Shutting down VM
E/AndroidRuntime(  688): ERROR: thread attach failed
</pre>		
<p>It's possible that the instrumentation apk isn't installed on your device or that the package name is incorrect in the Manifest file. </p>