A basic spoon task for Gradle to assemble debug apk, test apk, and execute spoon runner. (For a more robust implementation take a look at: https://github.com/stanfy/spoon-gradle-plugin)

spoon.gradle

def spoonRunner = "libs-uitests/spoon-runner-1.1.1-jar-with-dependencies.jar"

task spoon (dependsOn: ['assembleDebug', 'assembleDebugTest']) << {

    def rootDir = project.rootDir
    def localProperties = new File(rootDir, "local.properties")
    def sdkDir
    if (localProperties.exists()) {
        Properties properties = new Properties()
        localProperties.withInputStream { instr ->
            properties.load(instr)
        }

        sdkDir = properties.getProperty('sdk.dir')
    }

    def apk
    android.applicationVariants.each { variant ->
        if (variant.name == "debug") {
            apk = variant.outputFile
        }
    }

    def testApk
    android.testVariants.each { variant ->
        testApk = variant.outputFile
    }

    println "sdk=" + sdkDir
    println "apk=" + apk
    println "testApk=" + testApk

    exec {
        executable "java"
        args "-jar", spoonRunner,
            "--sdk", sdkDir,
            "--apk", apk,
            "--test-apk", testApk,
            "--output", "build/outputs/spoon/"
    }
}