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androidkotlinpowermockitoandroid-livedata

Testing LiveData using PowerMockRunner

My local unit tests use LiveData all the time. Normally, when you try to set a value on MutableLiveData you get

java.lang.RuntimeException: Method getMainLooper in android.os.Looper not mocked.

because local JVM has no access to Android framework. I fixed that using that:

@get:Rule
val rule = InstantTaskExecutorRule()

Everything was fine, until I had to use PowerMockito to mock a static method from google play library. Since I added 

@RunWith(PowerMockRunner::class)
@PrepareForTest(Tasks::class)

above my test class declaration I started to get this Looper not mocked error again. I used this rule before with MockitoJUnitRunner and everything was fine.

Solution

  • A bit late for the answer, but just faced the same issue and solved it!

    To use PowerMock and InstantTaskExecutorRule you need to add the following annotation:

    @RunWith(PowerMockRunner::class)
@PowerMockRunnerDelegate(MockitoJUnitRunner::class) //this line allows you to use the powermock runner and mockito runner
@PrepareForTest(UnderTestClass::class)
class UnderTestClassTest {

    @get:Rule
    var instantExecutorRule = InstantTaskExecutorRule()