Hilt Test Unit with View Model, No Instrumentation Registered

Question

I want to implementation Dependecy Injection using Hilt to ViewModel. And that working. but i can't test it. it show error. I was read some other post, but no one is answered.

This error maybe too many test dependency and conflict.

Version

Hilt version = 2.35.1 Android Studio = 4.2.1

Test class

simplest code won't run

package com.unlink.moviecatalogue6.ui.movie

import com.unlink.moviecatalogue6.data.repository.MovieRepository
import dagger.hilt.android.testing.HiltAndroidRule
import dagger.hilt.android.testing.HiltAndroidTest
import org.junit.Before
import org.junit.Rule
import org.junit.Test
import javax.inject.Inject

@HiltAndroidTest
class MovieViewModelTest {

    @get:Rule var hiltrule = HiltAndroidRule(this)

    @Inject
    lateinit var repository: MovieRepository

    @Before
    fun setUp() {
        hiltrule.inject()
    }

    @Test
    fun some(){
        //
    }
}

Error

but error at @get:Rule

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)
    at dagger.hilt.android.internal.testing.MarkThatRulesRanRule.<init>(MarkThatRulesRanRule.java:41)
    at dagger.hilt.android.testing.HiltAndroidRule.<init>(HiltAndroidRule.java:36)
    at com.unlink.moviecatalogue6.ui.movie.MovieViewModelTest2.<init>(MovieViewModelTest2.kt:19)
    at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
    at java.base/jdk.internal.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
    at java.base/java.lang.reflect.Constructor.newInstance(Constructor.java:490)
    at org.junit.runners.BlockJUnit4ClassRunner.createTest(BlockJUnit4ClassRunner.java:250)
    at org.junit.runners.BlockJUnit4ClassRunner.createTest(BlockJUnit4ClassRunner.java:260)
    at org.junit.runners.BlockJUnit4ClassRunner$2.runReflectiveCall(BlockJUnit4ClassRunner.java:309)
    at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
    at org.junit.runners.BlockJUnit4ClassRunner.methodBlock(BlockJUnit4ClassRunner.java:306)
    at org.junit.runners.BlockJUnit4ClassRunner$1.evaluate(BlockJUnit4ClassRunner.java:100)
    at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:366)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:103)
    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:63)
    at org.junit.runners.ParentRunner$4.run(ParentRunner.java:331)
    at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:79)
    at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:329)
    at org.junit.runners.ParentRunner.access$100(ParentRunner.java:66)
    at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:293)
    at org.junit.runners.ParentRunner$3.evaluate(ParentRunner.java:306)
    at org.junit.runners.ParentRunner.run(ParentRunner.java:413)
    at org.junit.runner.JUnitCore.run(JUnitCore.java:137)
    at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:69)
    at com.intellij.rt.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:33)
    at com.intellij.rt.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:220)
    at com.intellij.rt.junit.JUnitStarter.main(JUnitStarter.java:53)

Setup Custom Test Runner

i try make custom test runner

package com.unlink.moviecatalogue6

class CustomTestRunnerByMe : AndroidJUnitRunner() {
    override fun newApplication(
        cl: ClassLoader?,
        className: String?,
        context: Context?
    ): Application {
        return super.newApplication(cl, HiltTestApplication::class.java.name, context)
    }
}

here my full build.gradle

plugins {
    id 'com.android.application'
    id 'kotlin-android'
    id 'kotlin-kapt'
    id 'dagger.hilt.android.plugin'

}

android {
    compileSdkVersion 30
    buildToolsVersion "30.0.3"

    buildFeatures{

        viewBinding true
    }


    defaultConfig {
        applicationId "com.unlink.moviecatalogue6"
        minSdkVersion 21
        targetSdkVersion 30
        versionCode 1
        versionName "1.0"

        //custom test runner
        testInstrumentationRunner "com.unlink.moviecatalogue6.CustomTestRunnerByMe"
        //testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
        multiDexEnabled false
    }

    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
        }
    }
    compileOptions {
        sourceCompatibility JavaVersion.VERSION_1_8
        targetCompatibility JavaVersion.VERSION_1_8
    }
    kotlinOptions {
        jvmTarget = '1.8'
    }
}

dependencies {

    implementation "org.jetbrains.kotlin:kotlin-stdlib:$kotlin_version"
    implementation 'androidx.core:core-ktx:1.3.2'
    implementation 'androidx.appcompat:appcompat:1.2.0'
    implementation 'com.google.android.material:material:1.3.0'
    implementation 'androidx.constraintlayout:constraintlayout:2.0.4'

    // viewmodels
    implementation 'androidx.activity:activity-ktx:1.2.3'
    implementation 'androidx.fragment:fragment-ktx:1.3.3'

    //image library
    implementation 'de.hdodenhof:circleimageview:3.1.0'
    implementation 'com.github.bumptech.glide:glide:4.12.0'
    implementation 'androidx.legacy:legacy-support-v4:1.0.0'
    implementation 'androidx.palette:palette-ktx:1.0.0'



    //Retrofit
    implementation 'com.squareup.retrofit2:retrofit:2.9.0'
    implementation 'com.squareup.retrofit2:converter-gson:2.9.0'
    implementation "com.squareup.okhttp3:okhttp:5.0.0-alpha.2"
    implementation "com.squareup.okhttp3:logging-interceptor:5.0.0-alpha.2"

    //Kotlin Coroutines
    implementation "org.jetbrains.kotlinx:kotlinx-coroutines-core:$coroutines_android_version"
    implementation "org.jetbrains.kotlinx:kotlinx-coroutines-android:$coroutines_android_version"

    //Hilt
    implementation "com.google.dagger:hilt-android:$hilt_version"
    implementation "androidx.hilt:hilt-lifecycle-viewmodel:1.0.0-alpha03"
    kapt "com.google.dagger:hilt-android-compiler:$hilt_version"
    kapt "androidx.hilt:hilt-compiler:1.0.0"

    // default testing
    testImplementation 'junit:junit:4.13.2'
    androidTestImplementation 'androidx.test.ext:junit:1.1.2'


    // mockito testing
    testImplementation "androidx.arch.core:core-testing:2.1.0"
    testImplementation "org.mockito.kotlin:mockito-kotlin:3.2.0"

    //coroutine test
    //For runBlockingTest, CoroutineDispatcher etc.
    testImplementation "org.jetbrains.kotlinx:kotlinx-coroutines-test:1.4.2"

    // hilt testing
    // For Robolectric tests.
    testImplementation "com.google.dagger:hilt-android-testing:$hilt_version"
    kaptTest "com.google.dagger:hilt-android-compiler:$hilt_version"
    // For instrumented tests.
    androidTestImplementation "com.google.dagger:hilt-android-testing:$hilt_version"
    kaptAndroidTest "com.google.dagger:hilt-android-compiler:$hilt_version"


    // Espresso dependencies
    androidTestImplementation "androidx.test.espresso:espresso-core:$espresso_version"
    androidTestImplementation "androidx.test.espresso:espresso-contrib:$espresso_version"
    androidTestImplementation "androidx.test.espresso:espresso-intents:$espresso_version"
    androidTestImplementation "androidx.test.espresso:espresso-accessibility:$espresso_version"
    androidTestImplementation "androidx.test.espresso:espresso-web:$espresso_version"
    androidTestImplementation "androidx.test.espresso.idling:idling-concurrent:$espresso_version"
}

kapt{
    correctErrorTypes true
}

i was follow documentation at Hilt Documentation and Google Developer Document

Any response will very appreciate, Thanks for helping

Answer 1

Using RobolectricTestRunner,we can run the test that depends on the android framework without emulator or real device.

ViewModel is a android library.So to test the ViewModel need to add RobolectricTestRunner.

For that first add dependency

//Unit test 
    testImplementation 'org.robolectric:robolectric:4.4'

//UI test
androidTestImplementation 'org.robolectric:robolectric:4.4'

Then Add these code above your test class.

    @HiltAndroidTest
    @RunWith(RobolectricTestRunner.class)
    @Config(sdk = {Build.VERSION_CODES.VERSION_CODE}, application = HiltTestApplication.class)
    public class HiltMainViewModelTest{
          //your test code
}

Now your HiltCustomTestRunner will use RobolectricTestRunner to test android code.

Answer 2

 package com.unlink.moviecatalogue6.ui.movie import com.unlink.moviecatalogue6.data.repository.MovieRepository import dagger.hilt.android.testing.HiltAndroidRule import dagger.hilt.android.testing.HiltAndroidTest import org.junit.Before import androidx.test.ext.junit.runners.AndroidJUnit4 import org.junit.Rule import org.junit.Test import javax.inject.Inject @HiltAndroidTest @RunWith(AndroidJUnit4::class) class MovieViewModelTest { @get:Rule var hiltrule = HiltAndroidRule(this) @Inject lateinit var repository: MovieRepository @Before fun setUp() { hiltrule.inject() } @Test fun some(){ // } }

Add @RunWith(AndroidJUnit4::class)