failed: must deliver first message

[He-Pin]

refs: https://github.com/apache/pekko/actions/runs/16661369799/job/47159077349?pr=1894#step:7:10408

[07-31 22:45:38.371] [info] - must deliver first message *** FAILED *** (11 seconds, 310 milliseconds)
[07-31 22:45:38.371] [info]   java.lang.AssertionError: assertion failed: timeout (6 seconds) during expectMsg while waiting for OnNext(b)
[07-31 22:45:38.371] [info]   at scala.runtime.Scala3RunTime$.assertFailed(Scala3RunTime.scala:8)
[07-31 22:45:38.371] [info]   at org.apache.pekko.testkit.TestKitBase.expectMsg_internal(TestKit.scala:471)
[07-31 22:45:38.372] [info]   at org.apache.pekko.testkit.TestKitBase.expectMsg(TestKit.scala:448)
[07-31 22:45:38.372] [info]   at org.apache.pekko.testkit.TestKitBase.expectMsg$(TestKit.scala:168)
[07-31 22:45:38.372] [info]   at org.apache.pekko.testkit.TestKit.expectMsg(TestKit.scala:964)
[07-31 22:45:38.372] [info]   at org.apache.pekko.stream.testkit.TestSubscriber$ManualProbe.expectNext(StreamTestKit.scala:503)
[07-31 22:45:38.372] [info]   at org.apache.pekko.remote.artery.SendQueueSpec.test$1$$anonfun$1(SendQueueSpec.scala:184)
[07-31 22:45:38.372] [info]   at org.apache.pekko.remote.artery.SendQueueSpec.test$1$$anonfun$adapted$1(SendQueueSpec.scala:175)
[07-31 22:45:38.372] [info]   at scala.collection.immutable.Range.foreach(Range.scala:192)
[07-31 22:45:38.372] [info]   at org.apache.pekko.remote.artery.SendQueueSpec.test$1(SendQueueSpec.scala:175)
[07-31 22:45:38.372] [info]   at org.apache.pekko.remote.artery.SendQueueSpec.f$proxy5$1(SendQueueSpec.scala:215)
[07-31 22:45:38.372] [info]   at org.apache.pekko.remote.artery.SendQueueSpec.$init$$$anonfun$1$$anonfun$5(SendQueueSpec.scala:171)
[07-31 22:45:38.372] [info]   at org.scalatest.Transformer.apply$$anonfun$1(Transformer.scala:22)
[07-31 22:45:38.372] [info]   at org.scalatest.OutcomeOf.outcomeOf(OutcomeOf.scala:85)
[07-31 22:45:38.372] [info]   at org.scalatest.OutcomeOf.outcomeOf$(OutcomeOf.scala:31)
[07-31 22:45:38.372] [info]   at org.scalatest.OutcomeOf$.outcomeOf(OutcomeOf.scala:104)
[07-31 22:45:38.372] [info]   at org.scalatest.Transformer.apply(Transformer.scala:22)
[07-31 22:45:38.372] [info]   at org.scalatest.Transformer.apply(Transformer.scala:21)
[07-31 22:45:38.372] [info]   at org.scalatest.wordspec.AnyWordSpecLike$$anon$3.apply(AnyWordSpecLike.scala:1118)
[07-31 22:45:38.372] [info]   at org.scalatest.TestSuite.withFixture(TestSuite.scala:196)
[07-31 22:45:38.372] [info]   at org.scalatest.TestSuite.withFixture$(TestSuite.scala:138)
[07-31 22:45:38.372] [info]   at org.apache.pekko.testkit.PekkoSpec.withFixture(PekkoSpec.scala:79)
[07-31 22:45:38.372] [info]   at org.scalatest.wordspec.AnyWordSpecLike.invokeWithFixture$1(AnyWordSpecLike.scala:1124)
[07-31 22:45:38.372] [info]   at org.scalatest.wordspec.AnyWordSpecLike.runTest$$anonfun$1(AnyWordSpecLike.scala:1128)
[07-31 22:45:38.372] [info]   at org.scalatest.SuperEngine.runTestImpl(Engine.scala:306)
[07-31 22:45:38.372] [info]   at org.scalatest.wordspec.AnyWordSpecLike.runTest(AnyWordSpecLike.scala:1128)
[07-31 22:45:38.372] [info]   at org.scalatest.wordspec.AnyWordSpecLike.runTest$(AnyWordSpecLike.scala:44)
[07-31 22:45:38.372] [info]   at org.apache.pekko.testkit.PekkoSpec.runTest(PekkoSpec.scala:79)
[07-31 22:45:38.372] [info]   at org.scalatest.wordspec.AnyWordSpecLike.runTests$$anonfun$1(AnyWordSpecLike.scala:1187)
[07-31 22:45:38.372] [info]   at org.scalatest.SuperEngine.traverseSubNodes$1$$anonfun$1(Engine.scala:413)
[07-31 22:45:38.372] [info]   at scala.runtime.function.JProcedure1.apply(JProcedure1.java:15)
[07-31 22:45:38.372] [info]   at scala.runtime.function.JProcedure1.apply(JProcedure1.java:10)
[07-31 22:45:38.373] [info]   at scala.collection.immutable.List.foreach(List.scala:334)
[07-31 22:45:38.373] [info]   at org.scalatest.SuperEngine.traverseSubNodes$1(Engine.scala:429)
[07-31 22:45:38.373] [info]   at org.scalatest.SuperEngine.runTestsInBranch(Engine.scala:390)
[07-31 22:45:38.373] [info]   at org.scalatest.SuperEngine.traverseSubNodes$1$$anonfun$1(Engine.scala:427)
[07-31 22:45:38.373] [info]   at scala.runtime.function.JProcedure1.apply(JProcedure1.java:15)
[07-31 22:45:38.373] [info]   at scala.runtime.function.JProcedure1.apply(JProcedure1.java:10)
[07-31 22:45:38.373] [info]   at scala.collection.immutable.List.foreach(List.scala:334)
[07-31 22:45:38.373] [info]   at org.scalatest.SuperEngine.traverseSubNodes$1(Engine.scala:429)
[07-31 22:45:38.373] [info]   at org.scalatest.SuperEngine.runTestsInBranch(Engine.scala:396)
[07-31 22:45:38.373] [info]   at org.scalatest.SuperEngine.runTestsImpl(Engine.scala:475)
[07-31 22:45:38.373] [info]   at org.scalatest.wordspec.AnyWordSpecLike.runTests(AnyWordSpecLike.scala:1187)
[07-31 22:45:38.373] [info]   at org.scalatest.wordspec.AnyWordSpecLike.runTests$(AnyWordSpecLike.scala:44)
[07-31 22:45:38.373] [info]   at org.apache.pekko.testkit.PekkoSpec.runTests(PekkoSpec.scala:79)
[07-31 22:45:38.373] [info]   at org.scalatest.Suite.run(Suite.scala:1114)
[07-31 22:45:38.373] [info]   at org.scalatest.Suite.run$(Suite.scala:564)
[07-31 22:45:38.373] [info]   at org.apache.pekko.testkit.PekkoSpec.org$scalatest$wordspec$AnyWordSpecLike$$super$run(PekkoSpec.scala:79)
[07-31 22:45:38.373] [info]   at org.scalatest.wordspec.AnyWordSpecLike.run$$anonfun$1(AnyWordSpecLike.scala:1232)
[07-31 22:45:38.373] [info]   at org.scalatest.SuperEngine.runImpl(Engine.scala:535)
[07-31 22:45:38.373] [info]   at org.scalatest.wordspec.AnyWordSpecLike.run(AnyWordSpecLike.scala:1232)
[07-31 22:45:38.373] [info]   at org.scalatest.wordspec.AnyWordSpecLike.run$(AnyWordSpecLike.scala:44)
[07-31 22:45:38.373] [info]   at org.apache.pekko.testkit.PekkoSpec.org$scalatest$BeforeAndAfterAll$$super$run(PekkoSpec.scala:79)
[07-31 22:45:38.373] [info]   at org.scalatest.BeforeAndAfterAll.liftedTree1$1(BeforeAndAfterAll.scala:213)
[07-31 22:45:38.373] [info]   at org.scalatest.BeforeAndAfterAll.run(BeforeAndAfterAll.scala:217)
[07-31 22:45:38.374] [info]   at org.scalatest.BeforeAndAfterAll.run$(BeforeAndAfterAll.scala:135)
[07-31 22:45:38.374] [info]   at org.apache.pekko.testkit.PekkoSpec.run(PekkoSpec.scala:79)
[07-31 22:45:38.375] [info]   at org.scalatest.tools.Framework.org$scalatest$tools$Framework$$runSuite(Framework.scala:321)
[07-31 22:45:38.375] [info]   at org.scalatest.tools.Framework$ScalaTestTask.execute(Framework.scala:517)
[07-31 22:45:38.375] [info]   at sbt.ForkMain$Run.lambda$runTest$1(ForkMain.java:414)
[07-31 22:45:38.375] [info]   at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
[07-31 22:45:38.375] [info]   at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1136)
[07-31 22:45:38.375] [info]   at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:635)
[07-31 22:45:38.376] [info]   at java.base/java.lang.Thread.run(Thread.java:840)