I have a kotlin (test) class with the following import:
import com.sun.tools.attach.VirtualMachine
In IDEA I have added the tools.jar to the SDK classpath.
It runs fine in IDEA but I get errors when running from gradle in compileTestKotlin:
Unresolved reference: tools
Unresolved reference: VirtualMachine
Caused by: org.gradle.api.GradleException: Compilation error. See log for more details
    at org.jetbrains.kotlin.gradle.tasks.TasksUtilsKt.throwGradleExceptionIfError(tasksUtils.kt:8)
    at org.jetbrains.kotlin.gradle.tasks.KotlinCompile.processCompilerExitCode(Tasks.kt:415)
    at org.jetbrains.kotlin.gradle.tasks.KotlinCompile.callCompiler$kotlin_gradle_plugin(Tasks.kt:389)
    at org.jetbrains.kotlin.gradle.tasks.KotlinCompile.callCompiler$kotlin_gradle_plugin(Tasks.kt:251)
    at org.jetbrains.kotlin.gradle.tasks.AbstractKotlinCompile.execute(Tasks.kt:215)
How do I get the gradle build to use the tools.jar?
The key parts of build.gradle looks like this:
buildscript {
    ext.kotlin_version = '1.2.21'
    repositories {
        jcenter()
    }
    dependencies {
        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
    }
}
apply plugin: 'kotlin'
apply plugin: 'idea'
dependencies {
    compile "org.jetbrains.kotlin:kotlin-stdlib-jdk8:$kotlin_version"
    testCompile "org.jetbrains.kotlin:kotlin-test:$kotlin_version"
}
tasks.withType(org.jetbrains.kotlin.gradle.tasks.KotlinCompile).all {
    kotlinOptions {
        languageVersion = "1.1"
        apiVersion = "1.1"
        jvmTarget = "1.8"
        javaParameters = true   // Useful for reflection.
    }
}