Configuring Robolectric

Several aspects of Robolectric's behavior can be configured at runtime, using robolectric.properties files for package-level configuration, or @Config annotations for class-level or method-level configuration.

@Config Annotation

To configure Robolectric for a single test class or method, use the @Config annotation. The annotation can be applied to classes and methods; values specified at the method level will override values specified at the class level.

Base classes are also searched for annotations, so if you find yourself specifying the same values on a large number of tests, you can create a base class and move your @Config annotation to that class.

  @Config(sdk=JELLYBEAN_MR1,
      manifest="some/build/path/AndroidManifest.xml",
      shadows={ShadowFoo.class, ShadowBar.class})
  public class SandwichTest {
  }

robolectric.properties File

To configure all Robolectric tests within a package or group of packages, create a file named robolectric.properties in the appropriate package. Generally, this file would be placed within the appropriate package directory under src/test/resources in your project tree. Robolectric will search for properties files up the hierarchy of packages (including the unnamed default package at the top level), with values in deeper packages overriding values in more shallow packages. When test classes or methods have @Config annotations, those override any config from properties files.

Below is an example:

# src/test/resources/com/mycompany/app/robolectric.properties
sdk=18
manifest=some/build/path/AndroidManifest.xml
shadows=my.package.ShadowFoo,my.package.ShadowBar

Version note: Prior to Robolectric 3.1.3, only a top-level robolectric.properties file may be specified.

Global Configuration

If you wish to change the default for any configurable value for all your tests, you may extend RobolectricTestRunner and override the buildGlobalConfig() method, then specify your custom test runner using the @RunWith annotation.

Configurables

The following examples show how to handle common configuration tasks. For clarity, @Config annotations are used, but any of these values may also be configured using properties files.

Configure SDK Level

By default, Robolectric will run your code against the targetSdkVersion specified in your manifest. If you want to test your code under a different SDK, you can specify the SDK using the sdk, minSdk and maxSdk config properties:

@Config(sdk = { JELLY_BEAN, JELLY_BEAN_MR1 })
public class SandwichTest {

    public void getSandwich_shouldReturnHamSandwich() {
      // will run on JELLY_BEAN and JELLY_BEAN_MR1
    }

    @Config(sdk = KITKAT)
    public void onKitKat_getSandwich_shouldReturnChocolateWaferSandwich() {
      // will run on KITKAT
    }

    @Config(minSdk=LOLLIPOP)
    public void fromLollipopOn_getSandwich_shouldReturnTunaSandwich() {
      // will run on LOLLIPOP, M, etc.
    }
}

Note that sdk and minSdk/maxSdk may not be specified in the same config annotation or file; however, minSdk and maxSdk may be specified together. If any of them is present, they override any SDK specification from a less-specific configuration location.

Version note: Prior to Robolectric 3.2, minSdk and maxSdk are ignored, and NEWEST, OLDEST, and TARGET are not supported. Also, only integers corresponding to API levels may be specified in a properties file.

Configure Application Class

Robolectric will attempt to create an instance of your Application class as specified in the manifest. If you want to provide a custom implementation, you can specify it by setting:

@Config(application = CustomApplication.class)
public class SandwichTest {

    @Config(application = CustomApplicationOverride.class)
    public void getSandwich_shouldReturnHamSandwich() {
    }
}

Configure Resource and Asset Paths

Robolectric provides defaults for Gradle and Maven, but allows you to customize the path to your manifest, resource directory, and assets directory. This can be useful if you have a custom build system. You can specify these values by setting:

@Config(resourceDir = "some/build/path/res")
public class SandwichTest {

    @Config(resourceDir = "other/build/path/ham-sandwich/res")
    public void getSandwich_shouldReturnHamSandwich() {
    }
}

By default, Robolectric will assume that your resources and assets are located in directories named res and assets, respectively. These paths are assumed to be relative to the directory where the manifest is located. You can change these values by adding the resourceDir and assetDir options to the @Config annotaton.

Configure Qualifiers

You can explicitly configure the set of resource qualifiers in effect for a test:

public class SandwichTest {

    @Config(qualifiers = "fr-xlarge")
    public void getSandwichName() {
      assertThat(sandwich.getName()).isEqualTo("Grande Croque Monégasque");
    }
}

See Using Qualifiers for more details.

System Properties

Some additional options can be configured globally by setting these system properties:

When using Gradle, you can configure the System Properties for unit tests with the all block (see here). For example, to override the Maven repository URL and ID to download the runtime dependencies from a repository other than Sonatype:

android {
  testOptions {
    unitTests.all {
      systemProperty 'robolectric.dependency.repo.url', 'https://local-mirror/repo'
      systemProperty 'robolectric.dependency.repo.id', 'local'
    }
  }
}