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#

Answer 1

Spend hours on similar issue, and the problem wasn't in dependencies, rather in AndroidStudio itself Based on the answer:

IDE tries to run local unit tests instead of instrumented

.

Make sure it's run as instrumented test (red is local tests, green - instrumented):

After added instrumented test for the class it's run as expected under instrumented. How I done this? 2 ways I found:

1) Edit configuration (as on the last screenshot) and adding function manually

2) Under Project tap (top left corner) I selected Tests instead of android, found the test, right click - create test. After this step all new tests are run under instrumented tests

Answer 2

Simply check your import section:

import androidx.test.runner.AndroidJUnit4;

Answer 3

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.

Answer 4

I had similar error and was struggling a lot to fix it. My problem was that I was mixing AndroidJUnit4, InstrumentationRegistry, ApplicationProvider and AndroidJUnitRunnerversions / packages. Make sure they all are of the same generation. These are the classes that made it all run for me:

• androidx.test.runner.AndroidJUnitRunner
• androidx.test.platform.app.InstrumentationRegistry
• androidx.test.ext.junit.runners.AndroidJUnit4
• androidx.test.core.app.ApplicationProvider

for these I needed the following in the dependencies part of my build.gradle

androidTestImplementation 'androidx.test.espresso:espresso-core:3.1.1'
androidTestImplementation 'androidx.test:core:1.1.0'
androidTestImplementation 'androidx.test.ext:junit:1.1.0'
androidTestImplementation "com.android.support:support-annotations:27.1.1"
androidTestImplementation 'com.android.support.test:runner:1.0.2'
androidTestImplementation 'com.android.support.test:rules:1.0.2'

And of course the correct

testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"

in my defaultConfig of the build.gradle

Answer 5

I follow the official guide also met this issue, fix it with below steps.

Add testImplementation in app build.gradle

// Required -- JUnit 4 framework
testImplementation 'junit:junit:4.13.1'

testImplementation 'androidx.test:core-ktx:1.3.0'
testImplementation 'androidx.test.ext:junit-ktx:1.1.2'

// Robolectric environment
testImplementation 'org.robolectric:robolectric:4.4'

// Optional -- truth
testImplementation 'androidx.test.ext:truth:1.3.0'
testImplementation 'com.google.truth:truth:1.0'

// Optional -- Mockito framework
testImplementation 'org.mockito:mockito-core:3.3.3'

The official guide missed two testImplementations

testImplementation 'androidx.test.ext:junit-ktx:1.1.2'

testImplementation 'org.robolectric:robolectric:4.4'

Add testOptions block in app build.gradle

 android {
        // ...
        testOptions {
            unitTests.includeAndroidResources = true
        }
    }

Add @RunWith(AndroidJUnit4::class) to your test class

Example:

import android.content.Context
import android.os.Build.VERSION_CODES.Q
import androidx.test.core.app.ApplicationProvider
import androidx.test.ext.junit.runners.AndroidJUnit4
import com.google.common.truth.Truth.assertThat
import org.junit.Test
import org.junit.runner.RunWith
import org.robolectric.annotation.Config

@RunWith(AndroidJUnit4::class)
@Config(sdk = [Q])
class UnitTestWithContextDemoTest {

    private val context: Context = ApplicationProvider.getApplicationContext()
    
    fun test_getPackageName() {
        assertThat(context.packageName).contains("your_package_name")
    }
}

NOTE

@Config(sdk = [Q]) is required when your targetSdkVersion greater than 29. Because robolectric NOT support targetSdkVersion greater than 29.

Answer 6

Next things are not mentioned on google test guide, but they are what I found:

1. androidx.test in case of unit tests is just an interface/api (I don't know what about instrumented tests) and it needs implementations, which is robolectric library. That's why robolectric dependency is also required: testImplementation "org.robolectric:robolectric:{version}"
2. @RunWith(AndroidJUnit4.class) is required. To get nondeprecated class you need to add: testImplementation "androidx.test.ext:junit:{version}". By the way this dependency has transitive junit4 dependensy.

Also you can faced with: Failed to create a Robolectric sandbox: Android SDK 29 requires Java 9 (have Java 8) in case you use java 8 and compileSdkVersion 29 or above. Here you can find how to deal with it.