android - AndroidX : No instrumentation registered! Must run under a registering instrumentation

Question

I'm trying to run a local unit test that depends on the context, and was following this guide: https://developer.android.com/training/testing/unit-testing/local-unit-tests#kotlin and I set up my project like this (following this link : https://developer.android.com/training/testing/set-up-project ):

build.gradle(app)

android {
compileSdkVersion 28
buildToolsVersion '27.0.3'
defaultConfig {
    minSdkVersion 21
    targetSdkVersion 27
    versionCode 76
    versionName "2.6.0"
    testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
    multiDexEnabled true

useLibrary 'android.test.runner'
    useLibrary 'android.test.base'
    useLibrary 'android.test.mock'

}
testOptions {
    unitTests.returnDefaultValues = true
    unitTests.all {
        // All the usual Gradle options.
        testLogging {
            events "passed", "skipped", "failed", "standardOut", "standardError"
            outputs.upToDateWhen { false }
            showStandardStreams = true
        }
    }
    unitTests.includeAndroidResources = true

}
dependencies {
implementation fileTree(include: ['*.jar'], dir: 'libs')

androidTestImplementation("androidx.test.espresso:espresso-core:$espressoVersion", {
    exclude group: 'com.android.support', module: 'support-annotations'
})
// Espresso UI Testing dependencies
implementation "androidx.test.espresso:espresso-idling-resource:$espressoVersion"
androidTestImplementation "androidx.test.espresso:espresso-contrib:$espressoVersion"
androidTestImplementation "androidx.test.espresso:espresso-intents:$espressoVersion"

testImplementation 'androidx.test:core:1.0.0'

// AndroidJUnitRunner and JUnit Rules
androidTestImplementation 'androidx.test:runner:1.1.0'
androidTestImplementation 'androidx.test:rules:1.1.0'
// Espresso Assertions
androidTestImplementation 'androidx.test.ext:junit:1.0.0'
androidTestImplementation 'androidx.test.ext:truth:1.0.0'
androidTestImplementation 'com.google.truth:truth:0.42'
    implementation 'androidx.multidex:multidex:2.0.0'
}

My espresso_version is espressoVersion = '3.1.0'

My test that is located in module-name/src/test/java/ looks like this:

    import android.content.Context
import androidx.test.core.app.ApplicationProvider
import com.instacart.library.truetime.TrueTime
import edu.mira.aula.shared.extensions.android.trueDateNow
import edu.mira.aula.shared.network.ConnectivityHelper
import kotlinx.coroutines.experimental.runBlocking
import org.junit.Assert
import org.junit.Before
import org.junit.Test
import java.util.*
import java.util.concurrent.CountDownLatch

class TimeExtensionsUnitTest {
private lateinit var instrumentationCtx: Context

@Before
fun setup() {
    instrumentationCtx = ApplicationProvider.getApplicationContext<Context>()
}
 @Test
fun testTrueTimeValueReturnsIfInitialized() {
    if (ConnectivityHelper.isOnline(instrumentationCtx)) {
        runBlocking {
            val countDownLatch = CountDownLatch(1)
            TrueTime.build()
                    .withSharedPreferencesCache(instrumentationCtx)
                    .withConnectionTimeout(10000)
                    .initialize()
            countDownLatch.countDown()

            try {
                countDownLatch.await()
                val dateFromTrueTime = trueDateNow()
                val normalDate = Date()
                Assert.assertNotEquals(dateFromTrueTime, normalDate)
            } catch (e: InterruptedException) {
            }
        }
    }
}

Everytime I run it, it gives me:

java.lang.IllegalStateException: No instrumentation registered! Must run under a registering instrumentation.
 at androidx.test.platform.app.InstrumentationRegistry.getInstrumentation(InstrumentationRegistry.java:45)
  at androidx.test.core.app.ApplicationProvider.getApplicationContext(ApplicationProvider.java:41)

If I run it as a Instrumental Test(changing the package) it runs without errors. But I thought that this guide was exactly to be able to run unit test using Android Framework classes such as Context. I even tried run that class UnitTestSample but the same error occurs.

I also removed all android.support dependencies from my project

Any ideas on how to solve it?

Answer 1

Update

You should no longer encounter this error if youre using the latest gradle version.

---

I also encountered this issue.

If you look at migrating to Robolectric 4.0 here, it suggest to add the following line in your gradle.properties.

android.enableUnitTestBinaryResources=true

The problem is that, if you add this you your gradle.properties, it will output this warning:

WARNING: The option setting 'android.enableUnitTestBinaryResources=true' is experimental and unsupported.

Now, if you look at Robolectric releases here. You could see that this is a known issue where they state that

Android Gradle Plugin may report the following warning, which may be safely ignored: WARNING: The option setting 'android.enableUnitTestBinaryResources=true' is experimental and unsupported.. Android Gradle Plugin 3.4 will resolve this issue.

I believe unless you could update you gradle to 3.4. You won't be able to solve this issue.

What I did instead was to include Robolectric 4.0 as dependency.

testImplementation "org.robolectric:robolectric:4.0.2"

and annotate my test class with

@RunWith(RobolectricTestRunner::class)

This should make your test work.

Now when you run the test, you'll notice that Robolectric will log the following:

[Robolectric] NOTICE: legacy resources mode is deprecated; see http://robolectric.org/migrating/#migrating-to-40

Ignore this for now but as soon as you could update your gradle, migrate to the new Robolectric testing.