Fix TwoWayAgent deadlock in TaskCompletionSource constructor#56
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Pull request overview
Fixes a deadlock in TwoWayAgent.Tell() by correctly configuring TaskCompletionSource continuations to run asynchronously, and adds a regression test that reproduces the problematic synchronous-continuation scenario.
Changes:
- Replace incorrect
TaskContinuationOptions.RunContinuationsAsynchronouslyargument withTaskCreationOptions.RunContinuationsAsynchronouslywhen constructingTaskCompletionSourceinTwoWayAgent.Tell(). - Add a regression test that forces a synchronous continuation to call
Tell()again and validates it completes without blocking. - Normalize the test project file header (BOM removal / formatting-only change).
Reviewed changes
Copilot reviewed 3 out of 3 changed files in this pull request and generated 2 comments.
| File | Description |
|---|---|
| src/Dbosoft.Functional/Agent.cs | Fixes TaskCompletionSource construction so continuations don’t run inline on the ActionBlock thread. |
| test/Dbosoft.Functional.Tests/TwoWayAgentTests.cs | Adds regression coverage for the deadlock scenario via a synchronous continuation calling Tell() again. |
| test/Dbosoft.Functional.Tests/Dbosoft.Functional.Tests.csproj | Formatting-only change to the project file header. |
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…ource constructor TaskCompletionSource<T> was created with TaskContinuationOptions.RunContinuationsAsynchronously which silently matched the (object? state) overload instead of configuring async continuations. This caused SetResult() to run continuations inline, deadlocking when a continuation called Tell() on the same agent. Fixes #55
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- Fault or cancel the TaskCompletionSource when ActionBlock.Post() returns false, preventing callers from hanging indefinitely on a completed/canceled agent. - Remove unused System.Threading using in test file.
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Pull request overview
Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.
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Summary
TaskContinuationOptions→TaskCreationOptionsinTwoWayAgent.Tell()— the wrong enum was silently boxed asobjectstate instead of configuring async continuations, causing deadlocks when continuations callTell()on the same agent.Fixes #55
Test plan