fix: Add missing non-Task validation in generator failure recovery path#163
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YunchuWang merged 3 commits intoMar 11, 2026
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… recovery path
When an orchestrator catches a failed task exception and then yields a
non-Task value, the success path in resume() correctly throws an error
('The orchestrator generator yielded a non-Task object'), but the failure
recovery path silently returns without updating _previousTask. This
leaves the orchestration context in a broken state where:
1. _previousTask still points to the old failed task
2. The next resume() call re-throws the same exception to the generator
3. The orchestration gets stuck or produces confusing errors
The fix adds the same non-Task validation to the failure recovery path,
making it consistent with the success path. Two new tests verify both
the error case and the normal recovery case.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
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Pull request overview
This PR fixes a bug in the orchestration replay engine by making the generator “failure recovery” path validate yielded values the same way the “success” path already does, ensuring that yielding a non-Task after catching a task failure deterministically fails the orchestration (instead of silently returning in a broken state).
Changes:
- Add missing non-
Taskvalidation inRuntimeOrchestrationContext.resume()when resuming viagenerator.throw(...). - Add Jest coverage for (a) yielding a non-
Taskafter catching a failure and (b) yielding a valid recoveryTaskafter catching a failure.
Reviewed changes
Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.
| File | Description |
|---|---|
| packages/durabletask-js/src/worker/runtime-orchestration-context.ts | Adds the missing throw for non-Task yields in the failure recovery path of resume(). |
| packages/durabletask-js/test/orchestration_executor.spec.ts | Adds regression tests covering the failure-recovery yield validation behavior. |
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Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
kaibocai
approved these changes
Mar 11, 2026
YunchuWang
deleted the
copilot-finds/bug/fix-missing-non-task-validation-in-failure-path
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This was referenced Apr 16, 2026
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Summary
Add non-Task validation in the failure recovery path of
esume() to match the existing validation in the success path.
Closes #159
Problem
When an orchestrator catches a failed task exception and yields a non-Task value, the failure recovery path silently returns without error, leaving _previousTask pointing to the old failed task. The success path already correctly validates with hrow new Error('The orchestrator generator yielded a non-Task object').
Fix
Add the same validation error after the instanceof Task check in the failure recovery path.