durante l'esecuzione di un test Espresso utilizzando Android Studio. Ottengo il seguente errore

Question

Running tests 
    Test running started 
    java.lang.Exception: No runnable methods at org.junit.runners.BlockJUnit4ClassRunner.validateInstanceMethods(BlockJUnit4ClassRunner.java:166)at org.junit.runners.BlockJUnit4ClassRunner.collectInitializationErrors(BlockJUnit4ClassRunner.java:102) 
    at org.junit.runners.ParentRunner.validate(ParentRunner.java:344) 
    at org.junit.runners.ParentRunner.<init>(ParentRunner.java:74) 
    at org.junit.runners.BlockJUnit4ClassRunner.<init>(BlockJUnit4ClassRunner.java:55) 
    at android.support.test.internal.runner.junit4.AndroidJUnit4ClassRunner.<init>(AndroidJUnit4ClassRunner.java:38) 
    at android.support.test.runner.AndroidJUnit4.<init>(AndroidJUnit4.java:36) 
    at java.lang.reflect.Constructor.newInstance(Native Method) 
    at java.lang.reflect.Constructor.newInstance(Constructor.java:288) 
    at android.support.test.internal.runner.junit4.AndroidAnnotatedBuilder.buildAndroidRunner(AndroidAnnotatedBuilder.java:57) 
    at android.support.test.internal.runner.junit4.AndroidAnnotatedBuilder.runnerForClass(AndroidAnnotatedBuilder.java:45) 
    at org.junit.runners.model.RunnerBuilder.safeRunnerForClass(RunnerBuilder.java:57) 
    at org.junit.internal.builders.AllDefaultPossibilitiesBuilder.runnerForClass(AllDefaultPossibilitiesBuilder.java:29) 
    at org.junit.runner.C 

    omputer.getRunner(Computer.java:38) 
    at org.junit.runner.Computer$1.runnerForClass(Computer.java:29) 
    at org.junit.runners.model.RunnerBuilder.safeRunnerForClass(RunnerBuilder.java:57) 
    at org.junit.runners.model.RunnerBuilder.runners(RunnerBuilder.java:98) 
    at org.junit.runners.model.RunnerBuilder.runners(RunnerBuilder.java:84) 
    at org.junit.runners.Suite.<init>(Suite.java:79) 
    at org.junit.runner.Computer.getSuite(Computer.java:26) 
    at android.support.test.internal.runner.TestRequestBuilder.classes(TestRequestBuilder.java:691) 
    at 

android.support.test.internal.runner.TestRequestBuilder.build(TestRequestBuilder.java:654) 
at android.support.test.runner.AndroidJUnitRunner.buildRequest(AndroidJUnitRunner.java:329) 
at android.support.test.runner.AndroidJUnitRunner.onStart(AndroidJUnitRunner.java:226) 
at android.app.Instrumentation$InstrumentationThread.run(Instrumentation.java:1853) 

Fine

Answer 1

Accertarsi di aver definito questo nella vostra app/build.gradle ma non in build.gradle globale

testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"