Spock is using real methods even though object is mocked - spock

Question

In my app I use spock in version 2.0-M1-groovy-2.5. I have a problem that even though I mokced a class I get npe from the internals of mocked method.
I have simple class called ReactiveRestHighLevelClient which looks like this
open class ReactiveRestHighLevelClient(val restHighLevelClient: RestHighLevelClient, private val objectMapper: ObjectMapper) {
...
fun index(indexRequest: IndexRequest): Mono<IndexResponse> {
return Mono.create<IndexResponse> { sink ->
restHighLevelClient.indexAsync( // < -- HERE I GET THE NPE EVEN THOUGH THE METHOD IS MOCKED
indexRequest,
object : ActionListener<IndexResponse> {
override fun onFailure(e: Exception) {
e.printStackTrace()
sink.error(e)
}
override fun onResponse(response: IndexResponse) {
sink.success(response)
}
}
)
}
}
...
}
I have class ThreadModelElasticsearchService which uses the ReactiveRestHighLevelClient and looks like this:
#Component
class ThreadModelElasticsearchService(
private val objectMapper: ObjectMapper,
private val reactiveElasticsearchClient: ReactiveRestHighLevelClient,
private val extraFactsService: ExtraFactsService,
private val customerDataService: CustomerDataService,
rateLimiterRegistry: RateLimiterRegistry
) {
...
fun save(operationId: String, threadModel: ThreadModel): Mono<ThreadModel> {
val id = threadModel.threadId
?: ThreadModel.createKey(threadModel.partnerId, threadModel.customerId)
return reactiveElasticsearchClient
.index(
IndexRequest(ThreadModel.INDEX, ThreadModel.TYPE, id)
.source(objectMapper.writeValueAsString(threadModel), XContentType.JSON)
)
.thenReturn(threadModel)
.doOnNext { logger.info("[operation_id=$operationId] -- Saved : $it") }
.onErrorMap { e ->
logger.error("[operation_id=$operationId] -- Error calling elasticSearch", e)
ElasticRepositoryError(e)
}
.rateLimit(elasticRateLimiter)
}
...
}
Finally I have my test class called ThreadModelElasticsearchServiceTest which looks like this:
class ThreadModelElasticsearchServiceTest extends Specification {
ReactiveRestHighLevelClient reactiveElasticsearchClient = Mock()
... other mocks
ThreadModelElasticsearchService threadModelReactiveElasticsearchClient = new
ThreadModelElasticsearchService(objectMapper, reactiveElasticsearchClient, extraFactsService, customerDataService, RateLimiterRegistry.of(RateLimiterConfig.ofDefaults()))
def "should work"() {
given:
ThreadModel threadModel = new ThreadModel(...)
reactiveElasticsearchClient.index(_ as IndexRequest) >> Mono.just(indexResponse)
expect:
threadModelReactiveElasticsearchClient.save("should-work", threadModel).block()
}
When I run the tests I get execption like
java.lang.NullPointerException: null
at com.cb.elastic.search.api.elasticsearch.ReactiveRestHighLevelClient$index$1.accept(ReactiveRestHighLevelClient.kt:76)
which points to the body of the index method of the ReactiveRestHighLevelClient mock which is strange.
How to solve this ?