vscode-cowriting-plugin/sessions/0044/SESSION-0044.0-TRANSCRIPT-2026-06-13T07-40--2026-06-13T08-04.md

Session 0044.0 — Transcript

App: vscode-cowriting-plugin Start: 2026-06-13T07-40 (PST) Type: planning-and-executing End: 2026-06-13T08-04 (PST) Status: FINALIZED. Posture: autonomous (yolo)

Launch prompt

/goal plan-and-execute #47 (SLICE-2 of the document-edit flow — document edits propose per changed block: diffToBlockHunks INV-39 supersedes INV-37, word-precise intra-block attribution INV-40, block-insertion anchoring INV-41), per specs/coauthoring-document-edit-flow.md

Plan

SLICE-2 — #47 (review, P1) of the document-edit flow (specs/coauthoring-document-edit-flow.md §7.2). Anchor: Feature #47 (type/feature); covered by the graduated combined Solution Design → §4.3 R3.

Document rewrites propose one F4 proposal per changed block (the unit a human reviews), but each accept reconciles attribution at word granularity (the unit F3 records). INV-39 supersedes INV-37 for document edits; INV-40 word-precise intra-block attribution; INV-41 block-insertion anchoring. Selection edits unchanged.

Tasks:

1. model.ts — add optional granularity?: "block" | "single" to Proposal (additive, back-compat: absent ⇒ "single"). INV-39/§6.3.
2. proposalModel.ts — addProposal opts gains granularity, threaded onto the proposal (omitted when absent).
3. trackChangesModel.ts — new pure diffToBlockHunks(currentText, rewrittenText): EditHunk[]: split both sides into the existing block units (splitBlocksWithRanges for source ranges + splitBlocks keys), diff blocks (reuse diffArrays keying like diffBlocks), emit ONE EditHunk per changed/added/removed block — changed → [block.start,end)→rewrite; fences atomic (whole-fence hunk); inserted → anchored to adjacent boundary (INV-41, reuse the anchorInsertion idea); unchanged → none. Same EditHunk shape as diffToHunks (which is RETAINED as the intra-block sub-diff engine).
4. trackChangesPreview.ts — runEditAndPropose document branch uses diffToBlockHunks and tags each minted proposal granularity:"block".
5. proposalController.ts — accept: when granularity === "block", re-resolve the block text, diffToHunks(blockText, replacement) → per-run word sub-diff, apply one applyAgentEdit per changed run, descending offset so only the runs Claude changed land Claude-attributed; unchanged spans keep prior author (INV-40). Non-block keeps the single applyAgentEdit.
6. Tests: unit (diffToBlockHunks + INV-40 controller) + host E2E (#47 cases in §6.8); update the existing f11 document-path E2E (now per-block, supersedes INV-37 word-level expectation); docs/MANUAL-SMOKE-F12.md §2.

Design note (seam constraint): pendingEdits.matchEvent resolves ONE registration per change event, so INV-40's per-run attribution is implemented as sequential applyAgentEdit calls (descending offset), not a single multi-replace WorkspaceEdit. The spec's "one undo-grouped edit" wording is thus approximated as N undo steps per block accept — see Deferred decisions.

No new persisted artifact; no deploy pipeline (VS Code extension).

Results

SLICE-2 (#47, review, P1) shipped to main — PR #50 (merged), issue #47 closed.

• trackChangesModel.ts — new pure diffToBlockHunks (block-key alignment via diffArrays/diffBlocks keying; isolated changed block → block-aligned hunk → rewritten raw; fences atomic INV-23; insert/delete → exact gap-span hunk; zero-width gap-span anchored INV-41). Split diffToHunks into raw wordEditHunks + anchoring wrapper (fixes a latent overlap bug under batch apply).
• trackChangesPreview.ts — document branch uses diffToBlockHunks, tags granularity:"block".
• model.ts/proposalModel.ts — additive optional Proposal.granularity.
• proposalController.ts — acceptBlock: intra-block word sub-diff (wordEditHunks) → one applyAgentEdit per changed run, descending offset (INV-40 word-precise attribution; unchanged spans keep prior author).
• Tests: diffToBlockHunks unit (reconstruction/fence/add-remove); f12Review host E2E (M→M, unchanged→none, fence atomic, INV-40, INV-41); updated f11 document-path E2E to per-block; MANUAL-SMOKE-F12.md §2.

Verification: tsc --noEmit clean; 214 unit green; 69/5 host E2E green (main suite 65 → 69 net with the new F12 review tests).

Next: SLICE-3 — #46 (accept-all, INV-42): acceptAllProposals (controller, descending-order, orphan-skip + report) + cowriting.acceptAllProposals command

• preview toolbar Accept all button ({type:"acceptAll"} intent, shown ≥2 pending).

Session arc

1. Claim. Resumed via /goal next (after session 0043 shipped #42); claimed session 0044 for #47. Clean main baseline.
2. Anchor gate. #47 (type/feature) covered by the graduated combined design → §4.3 R3 satisfied.
3. Deep code read. splitBlocks*/diffBlocks/diffToHunks/EditHunk, runEditAndPropose, proposalController.accept/applyAgentEdit, and crucially pendingEdits.matchEvent (one registration per change event → drove the INV-40 sequential-apply decision).
4. TDD diffToBlockHunks. First attempt (coarsen word-hunks) failed a reconstruction case — discovered diffToHunks can emit OVERLAPPING hunks (anchorInsertion over-absorbs). Switched to block-key alignment with replacement-from-rewritten-raw → green.
5. Model + wiring + INV-40 accept. Added granularity; document branch → diffToBlockHunks; acceptBlock intra-block sub-diff. The overlap bug then resurfaced in acceptBlock (batch apply) → split diffToHunks into raw wordEditHunks (disjoint) + anchoring wrapper; acceptBlock uses raw → green.
6. Verified + shipped (214 unit, 69/5 E2E), self-reviewed, PR #50 merged, #47 closed, memory + transcript updated.

Deferred decisions

Autonomous-mode low-confidence calls the driver made and would have liked operator input on. Appended as the session runs; surfaced at finalize. Empty if none.

• INV-40 undo granularity (driver call). Spec §6.2/§6.7 say accepting a block proposal should be "one undo-grouped WorkspaceEdit." But the F3 seam's pendingEdits.matchEvent matches exactly ONE registration per change event, so a single WorkspaceEdit with N independent run-replaces can't carry per-run attribution (the multi-hunk event fails to match any single registration → falls through to human). Implemented INV-40 as sequential per-run applyAgentEdit calls, descending offset — correct word-precise attribution, reuses the seam with zero attribution-core risk, but a block accept is N undo steps rather than one. Single-undo-step would require extending matchEvent/onDidChange to consume multiple registrations per event (riskier F3 change) — left as a possible follow-up.