Kotlin Unit test instantiate for each test scenario

Question

Having a Unit test class with some arguments defined in construction

class VersionConsumerSpec {


    private val path = Paths.get("target").toAbsolutePath().toString()
    private val kafkaPort = (4000..8000).random()
    private val zooKeeperPort = (4000..8000).random()
    private val config: AppConfig = createAppConfig(kafkaPort)
    private val producer = createKafkaProducer()

    init {
        println("hello world")
    }

    @ExperimentalCoroutinesApi
    @ObsoleteCoroutinesApi
    @Test
    @DisplayName("test1")
    fun test1() {
    }

    @ExperimentalCoroutinesApi
    @ObsoleteCoroutinesApi
    @Test
    @DisplayName("test2")
    fun test2() {
    }

}

All the variables defined are executed for every test, even the init is executed twice here. Then I'm having issues since I want to declare all those variables once for all test cases.

I´m going something wrong here?, in Java or Scala this is not happening.

Is like if for each test the class would be completely instantiate again and again.

Answer 1

I guess that you are looking for @TestInstance annotation. PER_CLASS mode allows to create a new test instance once per test class.

@TestInstance(PER_CLASS)
class VersionConsumerSpec {
    ...