Unresolved reference jupiter and assertTrue when running Junit 5 Android tests

Question

I am trying to create an Android test class in Kotlin that deals with Bitmap but I can't manage to run the test because of these errors. They only occur for any test class in androidTest but the simple JVM tests in test run without problem.

First, this is how my test class looks like

import android.graphics.Bitmap
import androidx.test.core.app.ApplicationProvider
import org.junit.jupiter.api.Assertions.assertTrue

class RoundImageTest {

    @org.junit.jupiter.api.Test
    fun imagesRatio() {
        // test with square images
        val squareBitmap: Bitmap = Bitmap.createBitmap(
             164, 164, Bitmap.Config.ARGB_8888
        )
        assertTrue(squareBitmap.height == squareBitmap.width)
    }
}

Following the instructions specified here I have this in my project's build.gradle

dependencies {
    classpath 'com.android.tools.build:gradle:4.0.1'
    classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
    classpath 'eu.appcom.gradle:android-versioning:1.0.2'
    classpath 'com.github.dcendents:android-maven-gradle-plugin:2.1'
    classpath "io.gitlab.arturbosch.detekt:detekt-gradle-plugin:1.10.0"
    classpath "org.jlleitschuh.gradle:ktlint-gradle:9.2.1"
    classpath("de.mannodermaus.gradle.plugins:android-junit5:1.6.2.0")
    // NOTE: Do not place your application dependencies here; they belong
    // in the individual module build.gradle files
}

and this in my application's build.gradle

apply plugin: 'com.android.application'

apply plugin: 'kotlin-android'

apply plugin: 'kotlin-android-extensions'

apply plugin: 'eu.appcom.gradle.android-versioning'

apply plugin: 'maven'

apply plugin: 'kotlin-kapt'

def keystorePropertiesFile = rootProject.file("keystore.properties")
def keystoreProperties = new Properties()
keystoreProperties.load(new FileInputStream(keystorePropertiesFile))

android {
    compileSdkVersion 29
    defaultConfig {
        applicationId "com.example.demoapp"
        minSdkVersion 21
        targetSdkVersion 29
        versionCode versioning.getVersionCode()
        versionName versioning.getVersionName()
        testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
        vectorDrawables.useSupportLibrary = true
        javaCompileOptions {
            annotationProcessorOptions {
                arguments = [
                        "room.schemaLocation": "$projectDir/schemas" . toString(),
                        "room.incremental": "true",
                        "room.expandProjection": "true"
                ]
            }
        }
        testInstrumentationRunner = "androidx.test.runner.AndroidJUnitRunner"
        testInstrumentationRunnerArgument("runnerBuilder", "de.mannodermaus.junit5.AndroidJUnit5Builder")
    }
    testBuildType "alpha"
    sourceSets {
        main.java.srcDirs += 'src/main/kotlin'
        androidTest.assets.srcDirs += files("$projectDir/schemas" . toString())
    }
    signingConfigs {
        debug {
            keyAlias keystoreProperties['debugKeyAlias']
            keyPassword keystoreProperties['debugKeyPassword']
            storeFile file(rootDir.getCanonicalPath() + '/' + keystoreProperties['debugKeyStore'])
            storePassword keystoreProperties['debugStorePassword']
        }
        release {
            keyAlias keystoreProperties['releaseKeyAlias']
            keyPassword keystoreProperties['releaseKeyPassword']
            storeFile file(rootDir.getCanonicalPath() + '/' + keystoreProperties['releaseKeyStore'])
            storePassword keystoreProperties['releaseStorePassword']
        }
    }
    buildTypes {
        alpha {
            applicationIdSuffix ".alpha"
            debuggable true
            minifyEnabled false
            signingConfig signingConfigs.debug
            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
        }
        release {
            minifyEnabled true
            shrinkResources true
            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
            signingConfig signingConfigs.release
        }
    }
    compileOptions {
        sourceCompatibility JavaVersion.VERSION_1_8
        targetCompatibility JavaVersion.VERSION_1_8
    }
    testOptions {
        unitTests {
            includeAndroidResources = true
        }
    }
    packagingOptions {
        exclude 'META-INF/atomicfu.kotlin_module'
        exclude "META-INF/LICENSE*"
    }
    kotlinOptions {
        jvmTarget = "1.8"
    }
}

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

    // Kotlin
    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"

    // AndroidX
    implementation 'androidx.appcompat:appcompat:1.2.0'
    implementation 'androidx.core:core-ktx:1.3.1'
    implementation 'androidx.constraintlayout:constraintlayout:2.0.1'
    testImplementation 'androidx.test:core:1.3.0'

    // ACRA
    implementation "ch.acra:acra-mail:$acra_version"
    implementation "ch.acra:acra-notification:$acra_version"

    // Room components
    implementation "androidx.room:room-runtime:$room_version"
    implementation "androidx.room:room-ktx:$room_version"
    kapt "androidx.room:room-compiler:$room_version"
    androidTestImplementation "androidx.room:room-testing:$room_version"

    // Lifecycle components
    implementation "androidx.lifecycle:lifecycle-extensions:$lifecycle_version"
    implementation "androidx.lifecycle:lifecycle-common-java8:$lifecycle_version"
    androidTestImplementation "androidx.arch.core:core-testing:$androidx_version"

    // ViewModel Kotlin support
    implementation "androidx.lifecycle:lifecycle-viewmodel-ktx:$lifecycle_version"

    // Co-routines
    api "org.jetbrains.kotlinx:kotlinx-coroutines-android:$coroutines"

    // Material UI
    implementation "com.google.android.material:material:$material_version"

    // LeakCanary
    debugImplementation 'com.squareup.leakcanary:leakcanary-android:2.2'
    alphaImplementation 'com.squareup.leakcanary:leakcanary-android:2.2'

    // Navigation
    implementation 'androidx.navigation:navigation-fragment-ktx:2.3.0'
    implementation 'androidx.navigation:navigation-ui-ktx:2.3.0'

    // Junit
    testImplementation 'org.junit.jupiter:junit-jupiter-api:5.6.2'
    testRuntimeOnly 'org.junit.jupiter:junit-jupiter-engine:5.6.2'
    androidTestImplementation "androidx.test:runner:1.3.0"
    androidTestImplementation 'androidx.test.ext:junit:1.1.2'
    androidTestImplementation 'androidx.test.ext:junit-ktx:1.1.2'
    androidTestImplementation "de.mannodermaus.junit5:android-test-core:1.2.0"
    androidTestRuntimeOnly "de.mannodermaus.junit5:android-test-runner:1.2.0"

    // Espresso
    androidTestImplementation 'androidx.test.espresso:espresso-core:3.3.0'
    androidTestImplementation 'androidx.test:rules:1.3.0'
}

Now, when I try to run the test, this is what the Build Output shows me

Task :app:compileAlphaAndroidTestKotlin FAILED
e: RoundImageTest.kt: (5, 18): Unresolved reference: jupiter
e: RoundImageTest.kt: (9, 16): Unresolved reference: jupiter
e: RoundImageTest.kt: (16, 9): Unresolved reference: assertTrue
e: RoundImageTest.kt: (23, 9): Unresolved reference: assertTrue
e: RoundImageTest.kt: (30, 9): Unresolved reference: assertTrue

Answer 1

Apparently, what I had to do was change

testImplementation 'org.junit.jupiter:junit-jupiter-api:5.6.2'

to

androidTestImplementation 'org.junit.jupiter:junit-jupiter-api:5.6.2'