Upgrade to Robolectric 4.x

Migrating to 4.0

Project Configuration

Robolectric 4.0 requires Android Gradle Plugin 3.2 or greater.

Update the configuration in your module's build.gradle/build.gradle.kts file:

GroovyKotlin

android {
  compileSdkVersion 28 // Or newer
  testOptions.unitTests.includeAndroidResources = true
}

android {
  compileSdkVersion = 28 // Or newer
  testOptions.unitTests.isIncludeAndroidResources = true
}

Add the following in your gradle.properties file:

android.enableUnitTestBinaryResources=true

If you have dependencies on com.android.support.test, switch them to androidx.test; see Migrate to AndroidX.

Deprecations

3.8	4.0
`ShadowApplication.getInstance()`	`RuntimeEnvironment.application`
`ShadowApplication.getLatestAlertDialog()`	`ShadowAlertDialog.getLatestAlertDialog()`
`ShadowApplication.getLatestDialog()`	`ShadowDialog.getLatestDialog()`
`ShadowApplication.getLatestPopupMenu()`	`ShadowPopupMenu.getLatestPopupMenu()`
`ShadowLooper.getShadowMainLooper()`	`shadowOf(Looper.getMainLooper())`

The automatic migration tool includes a migration to help with this.

The following attributes of the @Config annotation are no longer supported when using binary resources mode:

assetDir and resourceDir: follow the recommended file structure of your build system.
manifest: Robolectric always uses the merged manifest generated by the Android toolchain. If your test was using a custom manifest you'll need to adapt it to not rely on that.
packageName: to change your package name, override the applicationId in your build system.

Improper Use of Shadows

Prior to Robolectric 4.0, it was possible (but ill-advised) to get the shadow for an Android framework object and invoke framework methods there. This could result in unexpected behavior (e.g., code in overridden methods in subclasses wouldn't be called). Shadow implementation methods are now marked protected to guard against this. Always invoke framework methods directly on the Android class.

3.8	4.0
`shadowOf(activity).finish();`	`activity.finish()`
`ShadowSystemClock.currentTimeMillis();`	`System.currentTimeMillis()`

The automatic migration tool will fix most of these for you.

`androidx.test`

Robolectric 4.0 includes initial support for androidx.test APIs. We strongly recommend adding the latest version of androidx.test:core as a test dependency and using those APIs whenever possible rather than using Robolectric-specific APIs.

3.8	4.0
`RuntimeEnvironment.application`	`ApplicationProvider.getApplicationContext()`
`ShadowMotionEvent`	`MotionEventBuilder`

Troubleshooting

Robolectric 4.0 replaces its old home-grown resource handling code with a direct adaptation of Android's resource handling code, using the full Android toolchain. This greatly improves fidelity to the behavior of a real Android device, but if your tests were relying on the quirks of the old code, you may need to fix your tests.

Some likely issues include:

android.view.InflateException: Binary XML file line #3: Failed to resolve attribute at index 17: TypedValue{t=0x2/d=0x7f01000e a=-1}

This happens when your Activity is using a theme that lacks values for certain attributes used by layouts. Make sure you've specified an appropriate theme for your activities in your AndroidManifest.