Demonstrates usage of CoroutinesIdlingResourceRule in our UI test.

MainActivityTest.kt

import android.support.test.espresso.Espresso.onView
import android.support.test.espresso.assertion.ViewAssertions.matches
import android.support.test.espresso.matcher.ViewMatchers.*
import android.support.test.runner.AndroidJUnit4
import android.view.View
import org.junit.Rule
import org.junit.Test
import org.junit.runner.RunWith

// https://gist.github.com/tomkoptel/1101b2bb61f3daf251e3d627ee533b92
import com.sample.CoroutinesIdlingResourceRule

@RunWith(AndroidJUnit4::class)
class MainActivityTest {
   val launchRule = ActivityTestRule<MainActivity>(MainActivity::class.java) 
   val coroutinesRule = CoroutinesIdlingResourceRule()
   
   @JvmField @Rule val chain = RuleChain.outerRule(coroutinesRule).around(launchRule)
   
   @Test
   fun some_test() {
     onView(withId(R.id.text)).check(matches(withText("Result")))
   }
}