https://pekko.apache.org/api/pekko/1.1/org/apache/pekko/stream/testkit/TestPublisher$$SubscriptionDone$.html
Apache Pekko 1.1.5 - org.apache.pekko.stream.testkit.TestPublisher.SubscriptionDone
Apache Pekko 1.1.5 - org.apache.pekko.stream.testkit.TestPublisher.SubscriptionDone
apachepekkostreamtestkit