Fix race condition in update_last_checkpoint#44801
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nathansobo merged 1 commit intomainfrom Dec 20, 2025
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update_last_checkpoint would call last_user_message() twice - once at the start to capture the checkpoint, and again in an async closure after the checkpoint comparison completed. If a new user message without a checkpoint was added between these two calls, the second call would find the new message and fail with 'no checkpoint'. Fix by capturing the user message's ID at the start and using user_message_mut(&id) in the async closure to find the specific message.
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update_last_checkpoint
rtfeldman
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Jan 5, 2026
Release Notes: - Fixed spurious "no checkpoint" error in agent panel --- ## Summary `update_last_checkpoint` would call `last_user_message()` twice - once at the start to capture the checkpoint, and again in an async closure after the checkpoint comparison completed. If a new user message without a checkpoint was added between these two calls, the second call would find the new message and fail with "no checkpoint". ## Fix Capture the user message ID at the start and use `user_message_mut(&id)` in the async closure to find the specific message. cc @mikayla-maki
LivioGama
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to LivioGama/zed
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Jan 20, 2026
Release Notes: - Fixed spurious "no checkpoint" error in agent panel --- ## Summary `update_last_checkpoint` would call `last_user_message()` twice - once at the start to capture the checkpoint, and again in an async closure after the checkpoint comparison completed. If a new user message without a checkpoint was added between these two calls, the second call would find the new message and fail with "no checkpoint". ## Fix Capture the user message ID at the start and use `user_message_mut(&id)` in the async closure to find the specific message. cc @mikayla-maki
LivioGama
pushed a commit
to LivioGama/zed
that referenced
this pull request
Jan 20, 2026
Release Notes: - Fixed spurious "no checkpoint" error in agent panel --- ## Summary `update_last_checkpoint` would call `last_user_message()` twice - once at the start to capture the checkpoint, and again in an async closure after the checkpoint comparison completed. If a new user message without a checkpoint was added between these two calls, the second call would find the new message and fail with "no checkpoint". ## Fix Capture the user message ID at the start and use `user_message_mut(&id)` in the async closure to find the specific message. cc @mikayla-maki
LivioGama
pushed a commit
to LivioGama/zed
that referenced
this pull request
Feb 15, 2026
Release Notes: - Fixed spurious "no checkpoint" error in agent panel --- ## Summary `update_last_checkpoint` would call `last_user_message()` twice - once at the start to capture the checkpoint, and again in an async closure after the checkpoint comparison completed. If a new user message without a checkpoint was added between these two calls, the second call would find the new message and fail with "no checkpoint". ## Fix Capture the user message ID at the start and use `user_message_mut(&id)` in the async closure to find the specific message. cc @mikayla-maki
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Release Notes:
Summary
update_last_checkpointwould calllast_user_message()twice - once at the start to capture the checkpoint, and again in an async closure after the checkpoint comparison completed. If a new user message without a checkpoint was added between these two calls, the second call would find the new message and fail with "no checkpoint".Fix
Capture the user message ID at the start and use
user_message_mut(&id)in the async closure to find the specific message.cc @mikayla-maki