chore(bus): avoid stop thread hop

[yordis]

• Avoids spending shutdown capacity on redundant thread pool dispatch when queue stops already provide asynchronous completion.
• Keeps shutdown failures and wait behavior observable under focused coverage.

[cursor]

PR Summary

Medium Risk
Changes shutdown/concurrency behavior by invoking queue Stop() inline and aggregating both synchronous and asynchronous failures; issues could surface as hangs or different exception timing during shutdown.

Overview
MultiQueuedHandler.Stop() now calls each queue’s Stop() directly (instead of dispatching via Task.Run), wrapping synchronous throws into Task.FromException and still awaiting all stops via Task.WhenAll.

Adds focused tests to verify Stop() waits for all queues, propagates stop failures, and still attempts to stop remaining queues even when one Stop() throws synchronously.

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ℹ️ Review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro

Run ID: f314b467-0b15-45a8-b8f3-23d26c810e7c

📥 Commits

Reviewing files that changed from the base of the PR and between 2f57f05 and 28f7589.

📒 Files selected for processing (2)

• src/EventStore.Core.XUnit.Tests/Bus/MultiQueuedHandlerTests.cs
• src/EventStore.Core/Bus/MultiQueuedHandler.cs

Walkthrough

MultiQueuedHandler.Stop() changes from wrapping per-queue stops in Task.Run to direct invocation, removing task factory overhead. RecordingQueuedHandler adds configurable stop task behavior, and two new async tests validate that the overall stop operation waits for all queues and propagates exceptions.

Changes

MultiQueuedHandler Stop Behavior

Layer / File(s)	Summary
Stop behavior change and validation src/EventStore.Core/Bus/MultiQueuedHandler.cs, src/EventStore.Core.XUnit.Tests/Bus/MultiQueuedHandlerTests.cs	MultiQueuedHandler.Stop() directly invokes queues[i].Stop() instead of wrapping in Task.Run(). RecordingQueuedHandler adds a StopTask property so tests can control queue stop behavior. Two new async tests verify that MultiQueuedHandler.Stop() waits for all queue stop tasks and propagates exceptions from failing queue stops.

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~10 minutes

Possibly related PRs

• TrogonStack/TrogonEventStore#70: Updates MultiQueuedHandler.Stop() to call underlying queue stops directly and adds tests for awaiting/exception propagation, building on prior async queue-shutdown changes.

Poem

🐰 A handler stops with grace so true,
Tasks await, no wrapping brew,
Exceptions flow where they belong,
Direct calls make the queue dance strong! ✨

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly and concisely describes the main change: avoiding redundant thread hops in the bus stop mechanism, which directly relates to the implementation change in MultiQueuedHandler.
Description check	✅ Passed	The description directly relates to the changeset by explaining the motivation: avoiding redundant thread pool dispatch and ensuring shutdown failures remain observable through test coverage.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch yordis/chore-bus-stop-directly

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[coderabbitai]

Actionable comments posted: 1

🤖 Prompt for all review comments with AI agents

Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

Inline comments:
In `@src/EventStore.Core/Bus/MultiQueuedHandler.cs`:
- Around line 49-52: MultiQueuedHandler.Stop currently calls queues[i].Stop()
directly into stopTasks[i], so a synchronous exception from a queue will
short-circuit the loop and prevent later queues from being stopped; fix this by
wrapping each call in a try/catch inside the loop in Stop: attempt to assign
stopTasks[i] = queues[i].Stop(), but if queues[i].Stop() throws synchronously
catch the exception and assign stopTasks[i] = Task.FromException(exception) (or
otherwise create a faulted Task) so the loop continues and all queues get a stop
invocation; reference MultiQueuedHandler.Stop, the queues array and stopTasks[]
when making the change.

🪄 Autofix (Beta)

Fix all unresolved CodeRabbit comments on this PR:

• Push a commit to this branch (recommended)
• Create a new PR with the fixes

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ℹ️ Review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro

Run ID: dc5df798-63e5-4454-85c9-4bac83b0e0f5

📥 Commits

Reviewing files that changed from the base of the PR and between 7373777 and 2f57f05.

📒 Files selected for processing (2)

• src/EventStore.Core.XUnit.Tests/Bus/MultiQueuedHandlerTests.cs
• src/EventStore.Core/Bus/MultiQueuedHandler.cs