akka/akka-core

Unstashed messages enqueued in TestActorRef mailbox while processing a message from self are stuck until another message is received

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#30,170 opened on Apr 7, 2021

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 (1 comment) (0 reactions) (0 assignees)Scala (3,547 forks)batch import
help wantednice-to-have (low-prio)t:testing

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Description

In the following workflow, unstashed messages are enqueued in the mailbox but are not processed as expected:

  1. Send message (messageOne) from TestKit to TestActorRef
  2. TestActorRef underlying actor stashes messageOne and schedules a subsequent message to self (selfMessage)
  3. selfMessage is sent and processed and messageOne is unstashed during processing of selfMessage
  4. messageOne is not processed
  5. Send another message (messageTwo) from TestKit to TestActorRef
  6. Both messageOne and messageTwo are processed

akka.testkit.CallingThreadDispatcher#runQueue appears to process the provided MessageQueue at the time of invocation rather than using the active Mailbox MessageQueue.

Contributor guide

Research direction
Examine the implementation of CallingThreadDispatcher.runQueue and how it handles the mailbox queue, particularly during stash/unstash operations.
Tech stack
scala
Domain
backend
Issue type
Bug
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
4
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
1-2 days
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
Active
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
Clear
Prerequisites
ScalaAkka
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
30