scala3: remove runtime trait ordering check (#30904)

.github/workflows/scala3-build.yml

@@ -21,7 +21,7 @@ jobs:
           - akka-testkit/test akka-actor-tests/test
           - akka-actor-testkit-typed/test akka-actor-typed-tests/test
           - akka-bench-jmh/test
-          - akka-cluster/test akka-cluster-tools/test akka-cluster-typed/test akka-distributed-data/test akka-cluster-metrics/test akka-cluster-sharding/Test/compile akka-cluster-sharding-typed/test
+          - akka-cluster/test akka-cluster-tools/test akka-cluster-typed/test akka-distributed-data/test akka-cluster-metrics/test akka-cluster-sharding/test akka-cluster-sharding-typed/test
           - akka-discovery/test akka-coordination/test
           - akka-persistence/test akka-persistence-shared/test akka-persistence-query/test akka-persistence-typed/test akka-persistence-testkit/test
           - akka-pki/test akka-slf4j/test

akka-persistence/src/main/scala-2/akka/persistence/TraitOrder.scala

@@ -0,0 +1,24 @@
+/*
+ * Copyright (C) 2021 Lightbend Inc. <https://www.lightbend.com>
+ */
+
+package akka.persistence
+
+import akka.annotation.InternalApi
+
+/**
+ * INTERNAL API
+ */
+@InternalApi
+private[persistence] object TraitOrder {
+  val canBeChecked = true
+
+  def checkBefore(clazz: Class[_], one: Class[_], other: Class[_]): Unit = {
+    val interfaces = clazz.getInterfaces
+    val i = interfaces.indexOf(other)
+    val j = interfaces.indexOf(one)
+    if (i != -1 && j != -1 && i < j)
+      throw new IllegalStateException(
+        s"For ${clazz.getName}, use ${one.getName} with ${other.getName}, instead of ${other.getName} with ${one.getName}")
+  }
+}

akka-persistence/src/main/scala-3/akka/persistence/TraitOrder.scala

@@ -0,0 +1,19 @@
+/*
+ * Copyright (C) 2021 Lightbend Inc. <https://www.lightbend.com>
+ */
+
+package akka.persistence
+
+import akka.annotation.InternalApi
+
+/**
+ * INTERNAL API
+ */
+@InternalApi
+private[persistence] object TraitOrder {
+  val canBeChecked = false
+
+  // No-op on Scala 3
+  def checkBefore(clazz: Class[_], one: Class[_], other: Class[_]): Unit =
+    ()
+}

akka-persistence/src/main/scala/akka/persistence/Eventsourced.scala

@@ -58,13 +58,7 @@ private[persistence] trait Eventsourced
   import JournalProtocol._
   import SnapshotProtocol.{ LoadSnapshotFailed, LoadSnapshotResult }
 
-  {
-    val interfaces = getClass.getInterfaces
-    val i = interfaces.indexOf(classOf[PersistentActor])
-    val j = interfaces.indexOf(classOf[akka.actor.Timers])
-    if (i != -1 && j != -1 && i < j)
-      throw new IllegalStateException("use Timers with PersistentActor, instead of PersistentActor with Timers")
-  }
+  TraitOrder.checkBefore(getClass, classOf[akka.actor.Timers], classOf[PersistentActor])
 
   private val extension = Persistence(context.system)
 

akka-persistence/src/test/scala/akka/persistence/TimerPersistentActorSpec.scala

@@ -101,9 +101,11 @@ class TimerPersistentActorSpec extends PersistenceSpec(ConfigFactory.parseString
     }
 
     "reject wrong order of traits, PersistentActor with Timer" in {
-      val pa = system.actorOf(Props[WrongOrder]())
-      watch(pa)
-      expectTerminated(pa)
+      if (TraitOrder.canBeChecked) {
+        val pa = system.actorOf(Props[WrongOrder]())
+        watch(pa)
+        expectTerminated(pa)
+      }
     }
 
     "handle AutoReceivedMessage's automatically" in {