Android 测试学习笔记（二）

Android 测试 TDD 持续集成

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Android 单元测试

• AndroidTestCase: 使用该类测试无需经过 Activity 即可获取 Context 和 Resources
  
  • getContext()

Mocking applications and preferences

• The RenamingMockContext class

  public class RenamingMockContext extends RenamingDelegatingContext {
    private static final String PREFIX = "test.";
    public RenamingMockContext(Context context)   {
       super(context, PREFIX);
    }
    @Override
    public SharedPreferences getSharedPreferences(String name, int    mode)   {
        return super.getSharedPreferences(PREFIX + name, mode);
    } // Now, we have full control over how preferences, databases, and files are stored.
  }

Mocking contexts

public class TemperatureConverterApplicationTests extends   
        ApplicationTestCase<TemperatureConverterApplication> {
    public TemperatureConverterApplicationTests() {
        this("TemperatureConverterApplicationTests");
    }
    public TemperatureConverterApplicationTests(String name)    {
        super(TemperatureConverterApplication.class);
        setName(name);
    }
    public void testSetAndRetreiveDecimalPlaces() {
        RenamingMockContext mockContext = new RenamingMockContext(getContext());
        setContext(mockContext);
        createApplication();
        TemperatureConverterApplication application = getApplication();
        application.setDecimalPlaces(3);
        assertEquals(3, application.getDecimalPlaces());
    }
}

public class TemperatureConverterApplication extends    Application {
    private static final int DECIMAL_PLACES_DEFAULT = 2;
    private static final String KEY_DECIMAL_PLACES = ".KEY_DECIMAL_PLACES";
    private SharedPreferences sharedPreferences;
    @Override
    public void onCreate() {
        super.onCreate();
        sharedPreferences = PreferenceManager.getDefaultSharedPreferences(this);
    }
    public void setDecimalPlaces(int places) {
        Editor editor = sharedPreferences.edit();
        editor.putInt(KEY_DECIMAL_PLACES, places);
        editor.apply();
    }
    public int getDecimalPlaces() {
        return sharedPreferences.getInt(KEY_DECIMAL_PLACES, DECIMAL_PLACES_DEFAULT);
    }
}

Testing activites

public class ForwardingActivity extends Activity {
    private static final int GHOSTBUSTERS = 999121212;
    @Override
    protected void onCreate(Bundle savedInstanceState)  {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_forwarding);
        View button = findViewById(R.id.forwarding_go_button);
        button.setOnClickListener(new View.OnClickListener()    {
            @Override
            public void onClick(View v) {
                Intent intent = new Intent("tel:" + GHOSTBUSTERS);
                startActivity(intent);
                finish();
            }
        });
    }
}

public class ForwardingActivityTest extends 
        ActivityUnitTestCase<ForwardingActivity> {
    private Intent startIntent;
    public ForwardingActivityTest() {
        super(ForwardingActivity.class);
    }
    @Override
    protected void setUp() throws Exception {
        super.setUp();
        Context context = getInstrumentation().getContext();
        startIntent = new Intent(context, ForwardingActivity.class);
    }
    public void testLaunchingSubActivityFiresIntentAndFinishesSelf() {
        Activity activity = startActivity(startIntent, null, null);
        View button = activity.findViewById(R.id.forwarding_go_button);
        button.performClick();
        assertNotNull(getStartedActivityIntent());
        assertTrue(isFinishCalled());
    }
    public void testExampleOfLifeCycleCreation() {
        Activity activity = startActivity(startIntent, null, null);
        getInstrumentation().callActivityOnStart(activity);
        getInstrumentation().callActivityOnResume(activity);
        // 进行测试
        getInstrumentation().callActivityOnPause(activity);
        // 进行测试
        getInstrumentation().callActivityOnStop(activity);
        // At this point, you could confirm that the activity has shut itself down appropriately,
        // or you could use a Mock Context to confirm that your activity has released any
        // system resources it should no longer be holding.
        // ActivityUnitTestCase.tearDown() is always automatically called
        // and will take care of calling onDestroy().
    }
}

Testing files, databases, and content providers

textView = (TextView) findViewById(R.id.mock_text_view);
try {
    FileInputStream fis = openFileInput(FILE_NAME);
    textView.setText(convertStreamToString(fis));
} catch (FileNotFoundException e) {
    textView.setText("File  not found");
}

$ adb shell    
$ echo "This is real data" > data/data/com.blundell.tut/files/my_file.txt
$ echo "This is *MOCK* data" > /data/data/com.blundell.tut/files/test.my_file.txt

public class MockContextExampleTest 
        extends ActivityUnitTestCase<MockContextExampleActivity> {
    private static final String PREFIX = "test.";
    private RenamingDelegatingContext mockContext;
    public MockContextExampleTest() {
        super(MockContextExampleActivity.class);
    }
    @Override
    protected void setUp() throws Exception {
        super.setUp();
        mockContext = new RenamingDelegatingContext(getInstrumentation().getTargetContext(),    PREFIX);
        mockContext.makeExistingFilesAndDbsAccessible();
    }
    public void testSampleTextDisplayed() {
        setActivityContext(mockContext);    // must called before startActivity()
        startActivity(new Intent(), null, null);
        assertEquals("This is *MOCK* data\n", getActivity().getText());
    }
}

Testing exceptions

public void testExceptionForLessThanAbsoluteZeroC() {
    try {
        TemperatureConverter.celsiusToFahrenheit(ABSOLUTE_ZERO_C - 1);
        fail();
    } catch (InvalidTemperatureException ex) {
        // do nothing we expect this exception!
    }
}

Testing local and remote services

public class DummyServiceTest extends ServiceTestCase<DummyService> {
    public DummyServiceTest() {
        super(DummyService.class);
    }
    public void testBasicStartup() {
        Intent startIntent = new Intent();
        startIntent.setClass(getContext(), DummyService.class);
        startService(startIntent);
    }
    public void testBindable() {
        Intent startIntent = new Intent();
        startIntent.setClass(getContext(), DummyService.class);
        bindService(startIntent);
    }
}

Extensive use of mock objects - About Mockito

dependencies {
    androidTestCompile('com.google.dexmaker:dexmaker-mockito:1.1')
}
packagingOptions {
    exclude 'META-INF/LICENSE'
    exclude 'folder/duplicatedFileName'
}

Exmaple

public void testTextChangedFilterWorksForCharacterInput() {
    assertEditNumberTextChangeFilter("A1A", "1");
}
/**
 * @param input the text to be filtered 
 * @param output the result you expect once the input has been filtered
 */
private void assertEditNumberTextChangeFilter(String input, String output)  {
    int lengthAfter = output.length();
    TextWatcher mockTextWatcher = mock(TextWatcher.class);
    editNumber.addTextChangedListener(mockTextWatcher);
    editNumber.setText(input);
    verify(mockTextWatcher).afterTextChanged(editableCharSequenceEq(output));
    verify(mockTextWatcher).onTextChanged(charSequenceEq(output), eq(0), eq(0), eq(lengthAfter));
    verify(mockTextWatcher).beforeTextChanged(charSequenceEq(""), eq(0), eq(0), eq(lengthAfter));
}

• Mockito: ArgumentMatcher

class CharSequenceMatcher extends ArgumentMatcher<CharSequence> {
    private final CharSequence expected;
    static CharSequence charSequenceEq(CharSequence expected) {
        return argThat(new CharSequenceMatcher(expected));
    }
    CharSequenceMatcher(CharSequence expected) {
        this.expected = expected;
    }
    @Override
    public boolean matches(Object actual) {
        return expected.toString().equals(actual.toString());
    }
    @Override
    public void describeTo(Description description) {
        description.appendText(expected.toString());
    }
}

Testing views in isolation

public class FocusTest extends AndroidTestCase  {
    private FocusFinder focusFinder;
    private ViewGroup layout;
    private Button leftButton;
    private Button centerButton;
    private Button rightButton;
    @Override
    protected void setUp() throws Exception {
        super.setUp();
        focusFinder = FocusFinder.getInstance();
        Context context = getContext();   // inflate the layout
        LayoutInflater inflater = LayoutInflater.from(context);
        layout = (ViewGroup) inflater.inflate(R.layout.view_focus, null);
        // manually measure it, and lay it out
        layout.measure(500, 500);
        layout.layout(0, 0, 500, 500);
        leftButton = (Button) layout.findViewById(R.id.focus_left_button);
        centerButton = (Button) layout.findViewById(R.id.focus_center_button);
        rightButton = (Button) layout.findViewById(R.id.focus_right_button);
    }
    public void testGoingRightFromLeftButtonJumpsOverCenterToRight() {
        View actualNextButton = focusFinder.findNextFocus(layout, leftButton, View.FOCUS_RIGHT);
        String msg = "right should be next focus from left";
        assertEquals(msg, this.rightButton, actualNextButton);
    }
    public void testGoingLeftFromRightButtonGoesToCenter() {
        View actualNextButton = focusFinder.findNextFocus(layout, rightButton, View.FOCUS_LEFT);
        String msg = "center should be next focus from right";
        assertEquals(msg, this.centerButton, actualNextButton);
    }
}

Testing parsers

public class ParserExampleActivityTest extends AndroidTestCase  {
    public void testParseXml() throws IOException {
        InputStream assetsXml = getContext().getAssets().open("my_document.xml");
        String result = parseXml(assetsXml);
        assertNotNull(result);
    }
}

　Testing for memory usage

public void assertNotInLowMemoryCondition() {
    //Verification: check if it is in low memory
    ActivityManager.MemoryInfo mi = new ActivityManager.MemoryInfo();
    ((ActivityManager)getActivity().getSystemService(Context.ACTIVITY_SERVICE)).getMemoryInfo(mi);
    assertFalse("Low memory condition", mi.lowMemory);
}
private String captureProcessInfo() {
    InputStream in = null;
    try {
        String cmd = "ps";
        Process p = Runtime.getRuntime().exec(cmd);
        in = p.getInputStream();
        Scanner scanner = new Scanner(in);
        scanner.useDelimiter("\\A");
        return scanner.hasNext() ? scanner.next() : "scanner error";
    } catch (IOException e) {
        fail(e.getLocalizedMessage());
    } finally {
        if (in != null) {
            try {
                in.close();
            } catch (IOException ignore) {
            }
        }
    }
    return  "captureProcessInfo error";
}
// Log.d(TAG, captureProcessInfo());

D/ActivityTest(1):  USER    PID     PPID    VSIZE   RSS     WCHAN       PC      State   NAME
D/ActivityTest(1):  root    1       0       312[KB] 220     c009b74c    0000ca4c    S   /init
D/ActivityTest(1):  root    2       0       0       0       c004e72c    00000000    S   kthreadd
D/ActivityTest(1):  root    3       2       0       0       c003fdc8    00000000    S   ksoftirqd/0
D/ActivityTest(1):  root    4       2       0       0       c004b2c4    00000000    S   events/0
D/ActivityTest(1):  root    5       2       0       0       c004b2c4    00000000    S   khelper
D/ActivityTest(1):  root    6       2       0       0       c004b2c4    00000000    S   suspend
D/ActivityTest(1):  root    7       2       0       0       c004b2c4    00000000    S   kblockd/0
D/ActivityTest(1):  root    8       2       0       0       c004b2c4    00000000    S   cqueue
D/ActivityTest(1):  root    9       2       0       0       c018179c    00000000    S   kseriod

Testing with Espresso

dependencies {
    // other dependencies
    androidTestCompile('com.android.support.test.espresso:espresso-core:2.0')
}
android {
    defaultConfig {
        // other configuration
        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
    }
    // Annoyingly there is a overlap with Espresso dependencies at the moment   
    // add this closure to fix internal jar file name clashes
    packagingOptions {
        exclude 'LICENSE.txt'
    }
}

public class ExampleEspressoTest extends    
        ActivityInstrumentationTestCase2<EspressoActivity> {
    public ExampleEspressoTest() {
        super(EspressoActivity.class);
    }
    @Override
    public void setUp() throws Exception {
        getActivity();
    }
    public void testClickingButtonShowsImage() {
        Espresso.onView(ViewMatchers.withId(R.id.espresso_button_order))
                                .perform(ViewActions.click());
        Espresso.onView(ViewMatchers.withId(R.id.espresso_imageview_cup))                                                           .check(ViewAssertions.matches(ViewMatchers.isDisplayed()));
    }
    public void testClickingButtonShowsImage()  {
        Espresso.onView(withId(R.id.espresso_button_order)).perform(click());
        Espresso.onView(withId(R.id.espresso_imageview_cup)).check(matches(isDisplayed()));
    }
}