Currently JUNIT5 API only allows @BeforeAll only on the method that is static
so if if do like this and this will not compile:
@BeforeAll
fun setup() {
MockitoAnnotations.initMocks(this)
mvc = MockMvcBuilders.standaloneSetup(controller).build()
}
so in order to have static method in Kotlin, I have to put in companion object like this:
companion object {
@JvmStatic
@BeforeAll
fun setup() {
MockitoAnnotations.initMocks(this)
mvc = MockMvcBuilders.standaloneSetup(smsController).build()
}
}
This will compile, but I don't have access to variables from parent class. So what would be idiomatic way to invoke @BeforeAll of JUnit5 with Kotlin?
As stated in the documentation of @BeforeAll:
Denotes that the annotated method should be executed before all @Test methods in the current class; analogous to JUnit 4’s @BeforeClass. Such methods must be static and are inherited.
The above is true for both Kotlin and Java. Keep in mind that by default Junit will create a separate instance of a test class per test case. It makes sense that @BeforeAll will only work with static methods since it's supposed to be invoked before any code of current test case. A static method has no access to instance members because it can be invoked without an instance.
As stated in Spring documentation:
The "standaloneSetup" on the other hand is a little closer to a unit test.
The example shows that you should just use instance members like so:
class StandaloneTest {
val smsController = ... // create instance of controller
val MockMvcBuilders.standaloneSetup(smcController).build()
}
The usefulness of @BeforeAll is limited and should generally be avoided as it potentially encourages runtime dependencies between test cases.