fix: resolve LogSource for getClass results on Scala 3

actor-tests/src/test/scala/org/apache/pekko/event/LogSourceSpec.scala

@@ -0,0 +1,56 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.pekko.event
+
+import org.apache.pekko
+import pekko.testkit.PekkoSpec
+
+object LogSourceSpec {
+  class LogsWithGetClass(system: pekko.actor.ActorSystem) {
+    // `getClass` returns `Class[? <: LogsWithGetClass]`, which did not compile on Scala 3
+    val log: LoggingAdapter = Logging(system, getClass)
+    val logSource: (String, Class[?]) = LogSource(getClass, system)
+  }
+}
+
+class LogSourceSpec extends PekkoSpec {
+  import LogSourceSpec._
+
+  "LogSource" must {
+
+    "resolve an implicit LogSource for the result of getClass" in {
+      val subject = new LogsWithGetClass(system)
+      subject.logSource._1 should ===(s"LogSourceSpec$$LogsWithGetClass($system)")
+      subject.logSource._2 should ===(classOf[LogsWithGetClass])
+      subject.log.isInstanceOf[BusLogging] should ===(true)
+    }
+
+    "resolve an implicit LogSource for a class literal" in {
+      val logSource: (String, Class[?]) = LogSource(classOf[LogsWithGetClass])
+      logSource._1 should ===("LogSourceSpec$LogsWithGetClass")
+      logSource._2 should ===(classOf[LogsWithGetClass])
+    }
+
+    "resolve an implicit LogSource for a wildcard class" in {
+      val c: Class[?] = classOf[LogsWithGetClass]
+      val logSource: (String, Class[?]) = LogSource(c)
+      logSource._1 should ===("LogSourceSpec$LogsWithGetClass")
+      logSource._2 should ===(classOf[LogsWithGetClass])
+    }
+  }
+}

actor/src/main/scala-2.13/org/apache/pekko/event/LogSourceCompat.scala

@@ -0,0 +1,28 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.pekko.event
+
+import org.apache.pekko.annotation.InternalApi
+
+/**
+ * INTERNAL API
+ *
+ * Scala 2 resolves [[LogSource.fromAnyClass]] for `getClass` results, so no extra implicits are needed.
+ */
+@InternalApi
+private[event] trait LogSourceCompat

actor/src/main/scala-3/org/apache/pekko/event/LogSourceCompat.scala

@@ -0,0 +1,33 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.pekko.event
+
+import org.apache.pekko.annotation.InternalApi
+
+/**
+ * INTERNAL API
+ *
+ * Lower priority implicits for [[LogSource]]. Scala 3 does not match `getClass`, which returns
+ * `Class[? <: T]`, against [[LogSource.fromAnyClass]]. This is not in the shared sources because
+ * Scala 2 reports it as ambiguous with `fromAnyClass`.
+ */
+@InternalApi
+private[event] trait LogSourceCompat {
+  implicit def fromAnySubClass[T]: LogSource[Class[? <: T]] =
+    LogSource.fromClass.asInstanceOf[LogSource[Class[? <: T]]]
+}

actor/src/main/scala/org/apache/pekko/event/Logging.scala

@@ -324,7 +324,7 @@ class DummyClassForStringSources
  * <li>anything else gives compile error unless implicit [[pekko.event.LogSource]] is in scope for it</li>
  * </ul>
  */
-object LogSource {
+object LogSource extends LogSourceCompat {
   implicit val fromString: LogSource[String] = new LogSource[String] {
     def genString(s: String) = s
     override def genString(s: String, system: ActorSystem) = s + "(" + system + ")"