From 9b174a31a6ddbbb1da3f899c2d3ea23c3973e793 Mon Sep 17 00:00:00 2001
From: Arnout Engelen <arnout@bzzt.net>
Date: Thu, 18 Nov 2021 14:44:43 +0100
Subject: [PATCH] scala3: remove runtime trait ordering check (#30904)

---
 .github/workflows/scala3-build.yml            |  2 +-
 .../scala-2/akka/persistence/TraitOrder.scala | 24 +++++++++++++++++++
 .../scala-3/akka/persistence/TraitOrder.scala | 19 +++++++++++++++
 .../scala/akka/persistence/Eventsourced.scala |  8 +------
 .../TimerPersistentActorSpec.scala            |  8 ++++---
 5 files changed, 50 insertions(+), 11 deletions(-)
 create mode 100644 akka-persistence/src/main/scala-2/akka/persistence/TraitOrder.scala
 create mode 100644 akka-persistence/src/main/scala-3/akka/persistence/TraitOrder.scala

diff --git a/.github/workflows/scala3-build.yml b/.github/workflows/scala3-build.yml
index fdc59ebf8c..059c5ba40d 100644
--- a/.github/workflows/scala3-build.yml
+++ b/.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
diff --git a/akka-persistence/src/main/scala-2/akka/persistence/TraitOrder.scala b/akka-persistence/src/main/scala-2/akka/persistence/TraitOrder.scala
new file mode 100644
index 0000000000..8fefd5269b
--- /dev/null
+++ b/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}")
+  }
+}
diff --git a/akka-persistence/src/main/scala-3/akka/persistence/TraitOrder.scala b/akka-persistence/src/main/scala-3/akka/persistence/TraitOrder.scala
new file mode 100644
index 0000000000..e97f576fbe
--- /dev/null
+++ b/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 =
+    ()
+}
\ No newline at end of file
diff --git a/akka-persistence/src/main/scala/akka/persistence/Eventsourced.scala b/akka-persistence/src/main/scala/akka/persistence/Eventsourced.scala
index 632d49c834..99cacbccf2 100644
--- a/akka-persistence/src/main/scala/akka/persistence/Eventsourced.scala
+++ b/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)
 
diff --git a/akka-persistence/src/test/scala/akka/persistence/TimerPersistentActorSpec.scala b/akka-persistence/src/test/scala/akka/persistence/TimerPersistentActorSpec.scala
index 675c753d0a..17d0a800bb 100644
--- a/akka-persistence/src/test/scala/akka/persistence/TimerPersistentActorSpec.scala
+++ b/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 {