Seperate Android Gradle Jvm version for app and unit tests

Question

Is it possible to set jvmTarget = "1.8" only for unit tests in gradle for an Android app? I was using:

tasks.withType(org.jetbrains.kotlin.gradle.tasks.KotlinCompile).all {
    kotlinOptions {
        jvmTarget = "1.8"
    }
}

But then I got crashes on older 4.4 devices...

Answer 1

Yes, you can do that simply by setting jvmTarget for a certain Kotlin compilation task.

In an Android project, the unit tests are normally compiled by the tasks compileDebugUnitTestKotlin , compileReleaseUnitTestKotlin etc. You may find the complete list of Gradle tasks in the IDE's Gradle view or by running:

./gradlew tasks --all

Search for the names following the pattern compile*Kotlin .

Then just configure the single task that you need, for example:

tasks.withType(org.jetbrains.kotlin.gradle.tasks.KotlinCompile)
    .matching { it.name == "compileDebugUnitTestKotlin" }
    .all { 
        kotlinOptions {
            jvmTarget = "1.8"
        }
    }