Kotlin + Junit build.gradle

build.gradle

apply plugin: 'com.android.application'
apply plugin: 'kotlin-android'

android {
    compileSdkVersion 22
    buildToolsVersion "22.0.1"

    defaultConfig {
        applicationId "com.****.*****"
        minSdkVersion 16
        targetSdkVersion 22
        versionCode 1
        versionName "1.0"
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }
    sourceSets {
        main.java.srcDirs += 'src/main/kotlin'
        test.java.srcDirs += 'src/test/kotlin'
    }

    testOptions {
        unitTests.returnDefaultValues = true
    }
}

dependencies {
    compile fileTree(dir: 'libs', include: ['*.jar'])
    compile 'com.android.support:appcompat-v7:22.2.0'
    compile "org.jetbrains.kotlin:kotlin-stdlib:$kotlin_version"
    compile 'com.google.code.gson:gson:2.3.1'
    compile 'com.squareup.retrofit:retrofit:1.9.0'
    compile 'com.squareup.okhttp:okhttp-urlconnection:2.0.0'
    compile 'com.squareup.okhttp:okhttp:2.0.0'

    testCompile 'junit:junit:4.12'

}

repositories {
    mavenCentral()
    maven { url "https://oss.sonatype.org/content/repositories/snapshots" }
}

buildscript {
    ext.kotlin_version = '0.12.1218'
    repositories {
        mavenCentral()
    }
    dependencies {
        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
    }
}