TestRepositoryTest.kt

import android.content.Context
import io.realm.*
import io.realm.internal.RealmCore
import io.realm.log.RealmLog
import org.junit.Before
import org.junit.Rule
import org.junit.Test
import org.junit.runner.RunWith
import org.mockito.Mockito.`when`
import org.mockito.Matchers.`any`
import org.powermock.core.classloader.annotations.PowerMockIgnore
import org.powermock.core.classloader.annotations.PrepareForTest
import org.powermock.core.classloader.annotations.SuppressStaticInitializationFor
import org.powermock.modules.junit4.PowerMockRunner
import org.powermock.modules.junit4.rule.PowerMockRule
import org.powermock.api.mockito.PowerMockito.mockStatic
import org.robolectric.RuntimeEnvironment
import org.robolectric.annotation.Config
import io.realm.RealmConfiguration
import org.powermock.api.mockito.PowerMockito.doNothing
import org.powermock.api.mockito.PowerMockito.mock
import org.powermock.api.mockito.PowerMockito.whenNew

/**
 * Check https://github.com/realm/realm-java/blob/master/examples/unitTestExample/src/test/java/io/realm/examples/unittesting/ExampleActivityTest.java
 */

@RunWith(PowerMockRunner::class)
@Config(constants = BuildConfig::class, sdk = intArrayOf(21))
@PowerMockIgnore("org.mockito.*", "org.robolectric.*", "android.*")
@SuppressStaticInitializationFor("io.realm.internal.Util")
@PrepareForTest(Realm::class, RealmConfiguration::class, RealmQuery::class, RealmResults::class, RealmCore::class, RealmLog::class)
class TestRepositoryTest {

  @JvmField @Rule public var rule = PowerMockRule()

  lateinit private var mockRealm: Realm

  @Before fun setup() {

    mockStatic(RealmCore::class.java)
    mockStatic(RealmLog::class.java)
    mockStatic(Realm::class.java)
    mockStatic(RealmConfiguration::class.java)
    Realm.init(RuntimeEnvironment.application)

    // Create the mock
    val mockRealm = mock(Realm::class.java)
    val mockRealmConfig = mock(RealmConfiguration::class.java)

    // TODO: Better solution would be just mock the RealmConfiguration.Builder class. But it seems there is some
    // problems for powermock to mock it (static inner class). We just mock the RealmCore.loadLibrary(Context) which
    // will be called by RealmConfiguration.Builder's constructor.
    doNothing().`when`(RealmCore::class.java)
    RealmCore.loadLibrary(`any`(Context::class.java))


    // TODO: Mock the RealmConfiguration's constructor. If the RealmConfiguration.Builder.build can be mocked, this
    // is not necessary anymore.
    whenNew(RealmConfiguration::class.java).withAnyArguments().thenReturn(mockRealmConfig)

    // Anytime getInstance is called with any configuration, then return the mockRealm
    `when`(Realm.getDefaultInstance()).thenReturn(mockRealm)

    this.mockRealm = mockRealm
  }

  //Stubbing
  @Test fun test() {}

}