fix(F3): align compress cut-point to user-message boundary - #78
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Track F-HIGH #3 from ROADMAP.md. ## Problem `handle_compress` (`ui/slash.rs:115-123`) did a reverse token-budget scan to pick the cut index, then drained `messages[..cut_idx]` into the summary. If that scan landed on an Assistant message, the kept tail started with [Assistant, …]. After compress, the session became [SystemSummary, Assistant, …] — broken role sequence. Anthropic and OpenAI reject with HTTP 400. The reverse-scan was content-only: it accumulated tokens until the threshold without considering role-boundary constraints. ## Fix New `align_cut_to_user_boundary(messages, cut_idx) -> usize` helper. Walks `cut_idx` forward until the message at that index is a `User` message (or the index reaches end-of-array). Called right after the existing reverse-scan, before any state mutation. Matches opencode's `splitTurn` discipline in `session/compaction.ts:161-184`. ## Tests 5 new tests in `ui::slash::tests`: - `align_cut_advances_past_assistant_to_next_user`: cut_idx landed on Assistant → advance to next User. - `align_cut_idempotent_when_already_on_user`: User-boundary cut unchanged. - `align_cut_past_end_clamps`: out-of-range index stays in range. - `align_cut_returns_end_when_no_user_in_tail`: no User after cut → return messages.len() (caller surfaces "nothing to compress"). - `align_cut_skips_system_to_user`: System messages (prior summaries) are also skipped — only User starts a kept tail. 656 pass (was 651). All build profiles clean.
yogthos
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All actionable Track F items now landed: - F-CRITICAL (PRs #76, #77): ACP perm asks routed to Deny, find/glob/list_dir hide dotfiles by default - F-HIGH (PRs #78–#84): compress aligns cut-point, read streams large files, ACP parallel tool ids, bash pgid cleanup, symlink canonicalize, session schema version, quote-aware bash splitter - F-MEDIUM (PRs #85, #86, #87, #89, #90, #91): interleaved bash output, compress net-savings, Retry-After parsing, plugin docs, relative-path normalize, BOM strip, bounded interject channel - F-SKIP (F9, F11, F15): verified false positives or N/A; rationale documented inline Status legend updated; ordering recommendation replaced with the shipped-status section. Co-authored-by: Yogthos <yogthos@gmail.com>
allen-munsch
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…e#78) Track F-HIGH #3 from ROADMAP.md. ## Problem `handle_compress` (`ui/slash.rs:115-123`) did a reverse token-budget scan to pick the cut index, then drained `messages[..cut_idx]` into the summary. If that scan landed on an Assistant message, the kept tail started with [Assistant, …]. After compress, the session became [SystemSummary, Assistant, …] — broken role sequence. Anthropic and OpenAI reject with HTTP 400. The reverse-scan was content-only: it accumulated tokens until the threshold without considering role-boundary constraints. ## Fix New `align_cut_to_user_boundary(messages, cut_idx) -> usize` helper. Walks `cut_idx` forward until the message at that index is a `User` message (or the index reaches end-of-array). Called right after the existing reverse-scan, before any state mutation. Matches opencode's `splitTurn` discipline in `session/compaction.ts:161-184`. ## Tests 5 new tests in `ui::slash::tests`: - `align_cut_advances_past_assistant_to_next_user`: cut_idx landed on Assistant → advance to next User. - `align_cut_idempotent_when_already_on_user`: User-boundary cut unchanged. - `align_cut_past_end_clamps`: out-of-range index stays in range. - `align_cut_returns_end_when_no_user_in_tail`: no User after cut → return messages.len() (caller surfaces "nothing to compress"). - `align_cut_skips_system_to_user`: System messages (prior summaries) are also skipped — only User starts a kept tail. 656 pass (was 651). All build profiles clean. Co-authored-by: Yogthos <yogthos@gmail.com>
allen-munsch
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Jun 3, 2026
…irge-code#92) All actionable Track F items now landed: - F-CRITICAL (PRs dirge-code#76, dirge-code#77): ACP perm asks routed to Deny, find/glob/list_dir hide dotfiles by default - F-HIGH (PRs dirge-code#78–dirge-code#84): compress aligns cut-point, read streams large files, ACP parallel tool ids, bash pgid cleanup, symlink canonicalize, session schema version, quote-aware bash splitter - F-MEDIUM (PRs dirge-code#85, dirge-code#86, dirge-code#87, dirge-code#89, dirge-code#90, dirge-code#91): interleaved bash output, compress net-savings, Retry-After parsing, plugin docs, relative-path normalize, BOM strip, bounded interject channel - F-SKIP (F9, F11, F15): verified false positives or N/A; rationale documented inline Status legend updated; ordering recommendation replaced with the shipped-status section. Co-authored-by: Yogthos <yogthos@gmail.com>
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Track F-HIGH #3. Compress's reverse token-budget scan could land cut_idx on a non-User message, breaking provider role sequencing after the System summary is inserted. New
align_cut_to_user_boundaryhelper walks cut_idx forward to the next User. 5 new tests, 656 pass.