AnimatorTestRule

class AnimatorTestRule : TestRule

JUnit TestRule that can be used to run Animators without actually waiting for the duration of the animation. This also helps the test to be written in a deterministic manner. Create an instance of AnimatorTestRule and specify it as a org.junit.ClassRule of the test class. Use advanceTimeBy to advance animators that have been started. Note that advanceTimeBy should be called from the same thread you have used to start the animator.

@SmallTest
@RunWith(AndroidJUnit4.class)
public class SampleAnimatorTest {

    @ClassRule
    public static AnimatorTestRule sAnimatorTestRule = new AnimatorTestRule();

    @UiThreadTest
    @Test
    public void sample() {
        final ValueAnimator animator = ValueAnimator.ofInt(0, 1000);
        animator.setDuration(1000L);
        assertThat(animator.getAnimatedValue(), is(0));
        animator.start();
        sAnimatorTestRule.advanceTimeBy(500L);
        assertThat(animator.getAnimatedValue(), is(500));
    }
}

Summary

AnimatorTestRule()

fun advanceTimeBy(timeDelta: Long): Unit

fun apply(base: Statement, description: Description): Statement

fun getCurrentTime(): Long