Why does this Spek on action not run?

Question

When I run this example code, all the code in the "on" action does not run in Android Studio. Do you know why? what is missing?

import org.jetbrains.spek.api.Spek  
import org.jetbrains.spek.api.dsl.describe  
import org.jetbrains.spek.api.dsl.given  
import org.jetbrains.spek.api.dsl.it 
import org.jetbrains.spek.api.dsl.on

@RunWith(JUnitPlatform::class) class SpekTest : Spek({
    val x = 2
    val y = 3

    given("x = $x and y = $y") {
        val sum = x + y

        on ("why does this not run?") {
            it("should be that x + y = 5") {
                assertEquals(5, sum)
            }

            it("should be that x - y = -1") {
                val subtract = x - y
                assertEquals(-111, subtract)
            }
        }

    } })

Answer 1

Make sure to update the spec version to be

testCompile group: 'org.jetbrains.spek', name: 'spek-api', version: '1.1.4'
testCompile group: 'org.jetbrains.spek', name: 'spek-junit-platform-engine', version: '1.1.4'