add test for notification handling being contravariant

Author: osoykan

projects/kediatr-core/src/test/kotlin/com/trendyol/kediatr/MediatorTests.kt

@@ -72,7 +72,8 @@ class MediatorTests : MediatorUseCases() {
       ConditionalPipelineBehavior(),
       TimingPipelineBehavior(),
       ComplexPipelineRequestHandler(),
-      ComplexDataRequestHandler()
+      ComplexDataRequestHandler(),
+      CatchAllNotificationsHandler()
     )
   )
 

projects/kediatr-core/src/testFixtures/kotlin/com/trendyol/kediatr/testing/MediatorUseCases.kt

@@ -109,12 +109,12 @@ abstract class MediatorUseCases : MediatorTestConvention() {
     val command = TestCommandForInheritanceWithFallback.TestCommandInherited1("id")
     testMediator.send(command)
     command.invocationCount().get() shouldBe 1
-    command.whereItWasInvokedFrom() shouldBe TestCommandForInheritanceWithFallbackHandlerHandler::class.java.name
+    command.whereItWasInvokedFrom() shouldContain TestCommandForInheritanceWithFallbackHandlerHandler::class.java.name
 
     val command2 = TestCommandForInheritanceWithFallback.TestCommandInherited2("id")
     testMediator.send(command2)
     command2.invocationCount().get() shouldBe 1
-    command2.whereItWasInvokedFrom() shouldBe TestRequestHandlerForCommandInherited2::class.java.name
+    command2.whereItWasInvokedFrom() shouldContain TestRequestHandlerForCommandInherited2::class.java.name
   }
 
   @Test
@@ -601,4 +601,13 @@ abstract class MediatorUseCases : MediatorTestConvention() {
     result shouldBe 2
     request.invocationCount().get() shouldBe 1
   }
+
+  @Test
+  fun notification_handling_is_contravariant_and_catch_all() = runTest {
+    val notification = TestNotification()
+    testMediator.publish(notification)
+    notification.invocationCount().get() shouldBe 1
+    notification.whereItWasInvokedFrom() shouldContain "CatchAllNotificationsHandler"
+    notification.whereItWasInvokedFrom() shouldContain "TestNotificationHandler"
+  }
 }

projects/kediatr-core/src/testFixtures/kotlin/com/trendyol/kediatr/testing/models.kt

@@ -20,10 +20,12 @@ abstract class EnrichedWithMetadata {
 
   fun invocationCount(): AtomicInteger = getMetadata(INVOCATION_COUNT) as? AtomicInteger ?: AtomicInteger(0)
 
-  fun whereItWasInvokedFrom(): String = getMetadata("invokedFrom") as? String ?: "unknown"
+  fun whereItWasInvokedFrom(): List<String> = invokedPlaces()
 
   fun invokedFrom(nameOfTheHandler: String) {
-    addMetadata("invokedFrom", nameOfTheHandler)
+    val invokedPlaces = invokedPlaces().toMutableList()
+    invokedPlaces.add(nameOfTheHandler)
+    addMetadata(INVOKED_FROM, invokedPlaces)
   }
 
   internal fun visitedPipeline(pipeline: String) {
@@ -42,6 +44,8 @@ abstract class EnrichedWithMetadata {
 
   fun orderedVisitedPipelines(): List<String> = getMetadata(ORDERED_VISITED_PIPELINES) as? List<String> ?: emptyList()
 
+  fun invokedPlaces(): List<String> = getMetadata(INVOKED_FROM) as? List<String> ?: emptyList()
+
   internal fun recordExecutionTime(time: Long) {
     addMetadata("executionTime", time)
   }
@@ -66,6 +70,7 @@ abstract class EnrichedWithMetadata {
     private const val INVOCATION_COUNT = "invocationCount"
     private const val VISITED_PIPELINES = "visitedPipelines"
     private const val ORDERED_VISITED_PIPELINES = "orderedVisitedPipelines"
+    private const val INVOKED_FROM = "invokedFrom"
   }
 }
 
@@ -93,6 +98,7 @@ class TestNotificationHandler(
   override suspend fun handle(notification: TestNotification) {
     mediator shouldNotBe null
     notification.incrementInvocationCount()
+    notification.invokedFrom("TestNotificationHandler")
   }
 }
 
@@ -999,3 +1005,11 @@ class FirstHandlerForCommand : RequestHandler.Unit<CommandWithMultipleHandlers>
 class SecondHandlerForCommand : RequestHandler.Unit<CommandWithMultipleHandlers> {
   override suspend fun handle(request: CommandWithMultipleHandlers) = Unit
 }
+
+class CatchAllNotificationsHandler : NotificationHandler<Notification> {
+  override suspend fun handle(notification: Notification) {
+    when (notification) {
+      is EnrichedWithMetadata -> notification.invokedFrom("CatchAllNotificationsHandler")
+    }
+  }
+}

projects/kediatr-koin-starter/src/test/kotlin/com/trendyol/kediatr/koin/MediatorTests.kt

@@ -86,6 +86,7 @@ class MediatorTests :
         single { SlowNotificationHandler2() }
         single { SlowNotificationHandler3() }
         single { SelfReferencingRequestHandler(get()) }
+        single { CatchAllNotificationsHandler() }
 
         // Extra
         single<MediatorAccessor> { { get<Mediator>() } }

projects/kediatr-quarkus-starter/src/test/kotlin/com/trendyol/kediatr/quarkus/MediatorTests.kt

@@ -198,4 +198,7 @@ class MediatorTests : MediatorUseCases() {
 
   @Produces
   fun selfReferencingRequestHandler(mediator: Mediator) = SelfReferencingRequestHandler { mediator }
+
+  @Produces
+  fun catchAllNotificationsHandler() = CatchAllNotificationsHandler()
 }

projects/kediatr-spring-boot-2x-starter/src/test/kotlin/com/trendyol/kediatr/spring/MediatorTests.kt

@@ -71,7 +71,8 @@ import org.springframework.context.annotation.*
     SlowNotificationHandler1::class,
     SlowNotificationHandler2::class,
     SlowNotificationHandler3::class,
-    SelfReferencingRequestHandler::class
+    SelfReferencingRequestHandler::class,
+    CatchAllNotificationsHandler::class
   ]
 )
 class MediatorTests : MediatorUseCases() {

projects/kediatr-spring-boot-3x-starter/src/test/kotlin/com/trendyol/kediatr/spring/MediatorTests.kt

@@ -71,7 +71,8 @@ import org.springframework.context.annotation.*
     SlowNotificationHandler1::class,
     SlowNotificationHandler2::class,
     SlowNotificationHandler3::class,
-    SelfReferencingRequestHandler::class
+    SelfReferencingRequestHandler::class,
+    CatchAllNotificationsHandler::class
   ]
 )
 class MediatorTests : MediatorUseCases() {