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wait_condition used poll_fn that ignored the waker context (_cx), returning Poll::Pending without registering any waker. This works at the top level of a workflow run method where the SDK re-polls unconditionally on every activation. However, when wait_condition is used inside a waker-based combinator like FuturesOrdered (e.g. via a ToolCallHandler future), the combinator never re-polls the inner future because no waker was triggered. Fix: store the waker from cx when returning Pending, and drain/wake all stored wakers after every state_mut call. This is deterministic because wakers are purely in-process scheduling — no I/O, timers, or randomness. All execution remains single-threaded on the LocalSet. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
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Exercises the exact bug scenario: wait_condition inside FuturesUnordered, which gives each sub-future its own waker and only re-polls when that waker fires. Without the waker fix, this test hangs because FuturesUnordered never re-polls the wait_condition future. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
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This was addressed on master in https://github.com/temporalio/sdk-core/pull/1118/changes
I pulled out the test to #1128 as we should have coverage for this.
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Great, I didn't realize that the release was from the master. |
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Summary
wait_conditionfutures are used inside waker-based combinators likeFuturesUnordered. Previously,wait_conditionreturnedPoll::Pendingwithout registering a waker, sostate_mutchanges would never re-poll the condition.condition_wakers: Rc<RefCell<Vec<Waker>>>toWorkflowContext— wakers are registered onPendingand drained/woken on everystate_mutcall.wait_condition+FuturesUnorderedwith a timer-triggered state mutation.Test plan
cargo check --testspasses with no new warningswait_condition_waker_in_futures_unorderedtest passes against mock history🤖 Generated with Claude Code