ClassTemplate with multiple invocations only creates one test class instance

[errikos]

Hello folks.

I have the following simple test class:

package com.cisco.iot.test.sample

import org.junit.jupiter.api.*
import org.junit.jupiter.api.extension.*
import java.util.stream.Stream
import kotlin.test.assertTrue

class CtInvocationContextProvider : ClassTemplateInvocationContextProvider {
    override fun supportsClassTemplate(context: ExtensionContext): Boolean = true
    override fun provideClassTemplateInvocationContexts(context: ExtensionContext): Stream<ClassTemplateInvocationContext> {
        return Stream.of(
            object : ClassTemplateInvocationContext {
                override fun prepareInvocation(context: ExtensionContext) {
                    context.getStore(ExtensionContext.Namespace.GLOBAL).put("hostPlatform", "HOST_PLATFORM_1")
                }
            },
            object : ClassTemplateInvocationContext {
                override fun prepareInvocation(context: ExtensionContext) {
                    context.getStore(ExtensionContext.Namespace.GLOBAL).put("hostPlatform", "HOST_PLATFORM_2")
                }
            },
        )
    }
}

class CtParameterResolver : ParameterResolver {
    override fun supportsParameter(parameterContext: ParameterContext, extensionContext: ExtensionContext): Boolean = true
    override fun resolveParameter(parameterContext: ParameterContext, extensionContext: ExtensionContext): Any =
        extensionContext.getStore(ExtensionContext.Namespace.GLOBAL).get("hostPlatform")
}

@ClassTemplate
@ExtendWith(
    CtInvocationContextProvider::class,
    CtParameterResolver::class,
)
@TestInstance(TestInstance.Lifecycle.PER_CLASS)
class SampleTest {
    @BeforeAll
    fun setup(hostPlatform: String) {
        println("Setting up test for hostPlatform: $hostPlatform")
    }

    @Test
    fun foo(hostPlatform: String) {
        println("Running foo test for hostPlatform: $hostPlatform")
        assertTrue(true)
    }
}

My purpose is to have two instances of SampleTest, each with its own hostPlatform. It seems that @ClassTemplate is not working as I expect it to here.

Essentially, only one instance of SampleTest is created and, what's worse, setup is being called before the CtInvocationContextProvider is called, resulting in the parameter of setup not being found.

Is this the expected behaviour here or am I missing something?

[errikos]

If I remove the parameter from setup then foo is indeed called twice but it seems that setup only runs once.

[sbrannen]

If I remove the parameter from setup then foo is indeed called twice but it seems that setup only runs once.

Have you taken a look at @BeforeParameterizedClassInvocation?

[errikos]

If I remove the parameter from setup then foo is indeed called twice but it seems that setup only runs once.

Have you taken a look at @BeforeParameterizedClassInvocation?

This saved me, thank you! I don't even need the extensions anymore, just annotate the class with @ParameterizedClass.