fix: prevent request_id desync from background events and duplicate Stopped - #40
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…topped Three fixes for the systematic n-1 response shift where each message gets the response for the previous message: 1. EntryUpdated uses turn-scoped request_id with prev_turn fallback: Claude Code delivers background events (tool completions, text flushes) asynchronously via session_notification after a turn ends. EntryUpdated now checks whether the entry belongs to the current turn (>= turn_start) or a previous one, and tags it with the correct turn's request_id. Previously it read the global THREAD_REQUEST_MAP which could already point to the next turn. 2. NewEntry updates turn_request_id only at turn boundaries: turn_request_id is now only updated from the global map when current == last_completed (i.e. a new turn is starting). The old value is rotated into prev_turn_request_id for use by late EntryUpdated events from the previous turn. 3. Guard normal-completion Stopped against duplicate emission: When cancel() races with natural turn completion, both paths could emit Stopped. The duplicate triggers the stale-detection fallback which reads the global map (now pointing to the next turn's request_id), sending a premature message_completed that shifts all subsequent responses by one. Added stopped_emitted_for_task check to the normal completion path, matching the existing guard on the cancelled path. Documented as Critical Fix #9 in portingguide.md. E2E tests pass for both zed-agent and claude (all 10 phases). Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
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Apr 14, 2026
Bump ZED_COMMIT to pick up helixml/zed#40 which fixes the systematic n-1 response shift caused by: - Background events from Claude Code tagged with wrong request_id - Duplicate Stopped events from cancel/completion race Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
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Test plan
cargo check -p external_websocket_syncandcargo check -p acp_threadpass🤖 Generated with Claude Code