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Examples
A few short specs showing what Spockk actually adds on top of plain Kotlin tests.
Specifications as documentation
Block descriptions turn a feature into a story anyone can read, engineer or not.
BridgeOperationsSpec.kt
kotlin
class BridgeOperationsSpec : Specification() {
fun `raising shields under attack`() {
given("the Enterprise cruising at impulse")
val enterprise = Enterprise()
`when`("a Klingon bird-of-prey decloaks nearby")
enterprise.raiseShields()
then("shields are at full strength")
enterprise.shieldStrength == 100
}
}Natural assertions
A bare condition is enough: no assertion framework required, and a failure renders a rich value diagram.
ShieldsSpec.kt
kotlin
fun `shields hold against a single torpedo hit`() {
given
val enterprise = Enterprise(shieldStrength = 100)
`when`
enterprise.absorbHit(30)
then
enterprise.shieldStrength == 70
}test output
text
Condition not satisfied:
enterprise.shieldStrength == 70
| | |
| 40 false
Enterprise(shieldStrength=40)Data-driven features
A data table declares feature iterations, exactly like Spock does in Groovy.
WarpFactorSpec.kt
kotlin
fun `warp factor #factor is within safety limits`(
factor: Int,
safe: Boolean
) {
expect
enterprise.isWarpSafe(factor) == safe
where
factor ; safe
1 ; true
6 ; true
10 ; false
}Test lifecycle fixtures
No annotations needed: Spockk recognizes them by name, same as Spock does in Groovy.
BridgeSystemsSpec.kt
kotlin
class BridgeSystemsSpec : Specification() {
fun setupSpec() {
enterprise.initializeDiagnostics()
}
fun `bridge and engineering report ready`() {
`when`
enterprise.runDiagnostics("bridge", "engineering")
then
enterprise.diagnostics.size == 2
cleanup
enterprise.resetDiagnostics()
}
}Interaction-based testing
Verify a collaborator was called, and stub its response - Spock's mocking syntax, natively in Kotlin.
BridgeOperationsSpec.kt
kotlin
fun `raising shields draws power from the deflector grid`() {
given
val powerGrid = Mock(PowerGrid::class.java)
val enterprise = Enterprise(powerGrid)
`when`
enterprise.raiseShields()
then
1 * powerGrid.divertPower(200)
}Experimental extension support
Spock's own extensions work in Spockk too.
WarpCoreSpec.kt
kotlin
class WarpCoreSpec : Specification() {
@FailsWith(WarpCoreBreachException::class)
fun `exceeding maximum warp causes a core breach`() {
expect
enterprise.engageWarp(10)
}
}