[codex] Reuse compacted history replacement for new context windows - #29762
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pakrym-oai
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June 24, 2026 01:36
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bolinfest
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Jun 24, 2026
| CompactedItem { | ||
| message: String::new(), | ||
| replacement_history: Some(replacement_history), | ||
| replacement_history: None, |
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Why isn't this set anymore?
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it's set inside replace_compacted_history call.
bolinfest
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Jun 24, 2026
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Why
start_new_context_windowindependently replaced in-memory history and persisted a compacted checkpoint instead of using the shared compacted-history path. That bypassed the centralized missing-item-ID assignment whenitem_idsis enabled, so fresh context messages could enter the new context window and its persisted replacement history without IDs.This follows up on the token-budget compaction reset flow introduced in #29743.
What changed
replace_compacted_history.Testing
just test -p codex-core start_new_context_window_assigns_and_persists_item_idsjust test -p codex-core new_context_tool_starts_new_window_before_follow_up