UnitTest＋Robolectric3.0の環境構築

Robolectric 3.0

Setup

Android Studio 1.2 で Robolectric3.0を準備する.

build.gradle

モジュールのbuild.gradleに下記ライブラリを追加.

    // UnitTest用.
    testCompile 'junit:junit:4.12'
    testCompile "org.mockito:mockito-core:1.9.5"

    // Robolectric用
    testCompile 'org.robolectric:robolectric:3.0-rc2'

Android gradle 1.1以降, AndroidStudioからのUnitTest実行がサポートされた.
http://tools.android.com/tech-docs/unit-testing-support

build.gradleの全容は下記.
app/build.gradle

Build VariantsのTest ArtifactをUnit Testsに設定し, test/javaでユニットテスト用のフォルダを作成しておく.

テストケースを書く

テストケースのRunnerにはRobolectricGradleTestRunner.classを指定.
ConfigアノテーションでGradleの出力パスをRobolectricに伝えるためBuildConfig.classを指定する.

@RunWith(RobolectricGradleTestRunner.class)
@Config(constants = BuildConfig.class, emulateSdk = 21)
public class MyTest {

テストケースの全容は下記.
MainActivityTest.java

テスト実行

現状だとテストを実行するには一手間必要である. そのままJUnitを実行すると次のエラーが発生する.

  java.io.FileNotFoundException: build/intermediates/bundles/debug/AndroidManifest.xml (No such file or directory)
  java.lang.UnsupportedOperationException: Robolectric does not support API level 1.

これを解決するためにRun configurationsからRobolectricを実行するプロファイルのworking directoryに$MODULE_DIR$を指定する.

参考：
https://github.com/robolectric/robolectric/issues/1648
http://robolectric.org/getting-started/ #Note for Mac Users

Point

dependencies {
    compile fileTree(dir: 'libs', include: ['*.jar'])
    compile 'com.android.support:appcompat-v7:22.1.1'

    // Unit test support on AndroidStudio. Android gradle version 1.1 or later Required.
    //  - see. http://tools.android.com/tech-docs/unit-testing-support
    testCompile 'junit:junit:4.12'
    testCompile "org.mockito:mockito-core:1.9.5"

    // If you are on a Mac, you will probably need to configure the default JUnit test runner configuration
    // in order to work around a bug where Android Studio does not set the working directory to the module being tested.
    // This can be accomplished by editing the run configurations, Defaults -> JUnit and changing the working directory value to $MODULE_DIR$.
    //  - Resolved java.io.FileNotFoundException: build/intermediates/bundles/debug/AndroidManifest.xml (No such file or directory)
    //  - Resolved java.lang.UnsupportedOperationException: Robolectric does not support API level 1.
    //  - see. https://github.com/robolectric/robolectric/issues/1648
    //  - see. http://robolectric.org/getting-started/#Note for Mac Users
    testCompile 'org.robolectric:robolectric:3.0-rc2'
}

@RunWith(RobolectricGradleTestRunner.class)
@Config(constants = BuildConfig.class, emulateSdk = 21)
public class MainActivityTest {
    @Before
    public void setUp() throws Exception {
        ShadowLog.stream = System.out;
    }

    @Test
    public void HelloRobolectric() throws Exception {
        final MainActivity activity = Robolectric.setupActivity(MainActivity.class);
        activity.onCreate(null);
        Log.d("yuki", "Hello Robolectric");
    }
}

以上.