Fix ManualTime.expectNoMessageFor async delivery race

actor-testkit-typed/src/main/scala/org/apache/pekko/actor/testkit/typed/javadsl/ManualTime.scala

@@ -72,10 +72,16 @@ final class ManualTime(delegate: pekko.testkit.ExplicitlyTriggeredScheduler) {
    */
   def timePasses(amount: Duration): Unit = delegate.timePasses(amount.toScala)
 
+  /**
+   * Advance the clock by the specified duration and assert that the probes receive no messages.
+   *
+   * After advancing the clock, each probe waits for the configured
+   * `pekko.actor.testkit.typed.expect-no-message-default` duration so that asynchronously dispatched messages can arrive.
+   */
   @varargs
   def expectNoMessageFor(duration: Duration, on: TestProbe[?]*): Unit = {
     delegate.timePasses(duration.toScala)
-    on.foreach(_.expectNoMessage(Duration.ZERO))
+    on.foreach(_.expectNoMessage())
   }
 
 }

actor-testkit-typed/src/main/scala/org/apache/pekko/actor/testkit/typed/scaladsl/ManualTime.scala

@@ -14,7 +14,7 @@
 package org.apache.pekko.actor.testkit.typed.scaladsl
 
 import scala.annotation.varargs
-import scala.concurrent.duration.{ Duration, FiniteDuration }
+import scala.concurrent.duration.FiniteDuration
 
 import org.apache.pekko
 import pekko.actor.typed.ActorSystem
@@ -72,10 +72,16 @@ final class ManualTime(delegate: pekko.testkit.ExplicitlyTriggeredScheduler) {
    */
   def timePasses(amount: FiniteDuration): Unit = delegate.timePasses(amount)
 
+  /**
+   * Advance the clock by the specified duration and assert that the probes receive no messages.
+   *
+   * After advancing the clock, each probe waits for the configured
+   * `pekko.actor.testkit.typed.expect-no-message-default` duration so that asynchronously dispatched messages can arrive.
+   */
   @varargs
   def expectNoMessageFor(duration: FiniteDuration, on: TestProbe[?]*): Unit = {
     delegate.timePasses(duration)
-    on.foreach(_.expectNoMessage(Duration.Zero))
+    on.foreach(_.expectNoMessage())
   }
 
 }

actor-testkit-typed/src/test/scala/org/apache/pekko/actor/testkit/typed/scaladsl/ManualTimeSpec.scala

@@ -0,0 +1,122 @@
+/*
+ * 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.actor.testkit.typed.scaladsl
+
+import java.time.{ Duration => JDuration }
+import java.util.concurrent.{ CountDownLatch, TimeUnit }
+
+import scala.concurrent.duration._
+
+import org.apache.pekko
+import pekko.Done
+import pekko.actor.testkit.typed.scaladsl.ManualTimeSpec.config
+import pekko.actor.typed.DispatcherSelector
+import pekko.actor.typed.scaladsl.Behaviors
+
+import org.scalatest.wordspec.AnyWordSpecLike
+
+import com.typesafe.config.ConfigFactory
+
+object ManualTimeSpec {
+  val config = ConfigFactory
+    .parseString("""
+      manual-time-test-dispatcher {
+        type = Dispatcher
+        executor = "thread-pool-executor"
+        thread-pool-executor.fixed-pool-size = 1
+        throughput = 1
+      }
+      pekko.actor.testkit.typed.expect-no-message-default = 3 s
+    """)
+    .withFallback(ManualTime.config)
+}
+
+class ManualTimeSpec extends ScalaTestWithActorTestKit(config) with AnyWordSpecLike with LogCapturing {
+
+  private val manualTime = ManualTime()
+
+  private def verifyDelayedMessageIsDetected(expectNoMessageFor: TestProbe[String] => Unit): Unit = {
+    val target = TestProbe[String]()
+    val timerStarted = TestProbe[Done]()
+    val dispatcherSelector = DispatcherSelector.fromConfig("manual-time-test-dispatcher")
+
+    spawn(
+      Behaviors.withTimers[String] { timers =>
+        timers.startSingleTimer("unexpected", 1.milli)
+        timerStarted.ref ! Done
+        Behaviors.receiveMessage { message =>
+          target.ref ! message
+          Behaviors.same
+        }
+      },
+      dispatcherSelector)
+    timerStarted.expectMessage(Done)
+
+    val dispatcherBlocked = new CountDownLatch(1)
+    val releaseDispatcher = new CountDownLatch(1)
+    val blocker = spawn(
+      Behaviors.receiveMessage[Done] { _ =>
+        dispatcherBlocked.countDown()
+        releaseDispatcher.await()
+        Behaviors.stopped
+      },
+      dispatcherSelector)
+    blocker ! Done
+    dispatcherBlocked.await(3, TimeUnit.SECONDS) shouldBe true
+
+    val testThread = Thread.currentThread()
+    val watcherDone = new CountDownLatch(1)
+    system.scheduler.scheduleOnce(
+      2.millis,
+      () => {
+        val watcher = new Thread(
+          () => {
+            try {
+              while (releaseDispatcher.getCount != 0 && testThread.getState != Thread.State.TIMED_WAITING)
+                Thread.onSpinWait()
+              if (testThread.getState == Thread.State.TIMED_WAITING)
+                releaseDispatcher.countDown()
+            } finally watcherDone.countDown()
+          },
+          "manual-time-expect-no-message-watcher")
+        watcher.setDaemon(true)
+        watcher.start()
+      })(system.executionContext)
+
+    try {
+      intercept[AssertionError] {
+        expectNoMessageFor(target)
+      }.getMessage should include("Received unexpected message unexpected")
+    } finally {
+      releaseDispatcher.countDown()
+      watcherDone.await(3, TimeUnit.SECONDS) shouldBe true
+    }
+  }
+
+  "ManualTime.expectNoMessageFor" must {
+    "detect a delayed message with the Scala DSL" in {
+      verifyDelayedMessageIsDetected(probe => manualTime.expectNoMessageFor(2.millis, probe))
+    }
+
+    "detect a delayed message with the Java DSL" in {
+      val javaManualTime = pekko.actor.testkit.typed.javadsl.ManualTime.get(system)
+      verifyDelayedMessageIsDetected(probe =>
+        javaManualTime.expectNoMessageFor(JDuration.ofMillis(2), probe.asJava))
+    }
+  }
+}