fix(edit): kill the auto-format edit-rejection round-trip#57
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The local model's #1 reported friction: the write-guard reformats a file right after create/edit (eslint --fix + prettier), so the model's next edit oldString no longer matches disk → not-found → a wasted turn re-reading the file. Two fixes: - fuzzyLineReplace now also tolerates a line-trailing comma/semicolon (prettier adds trailing commas in multiline literals/args and normalizes semicolons), so more near-miss edits land silently. Unique-window guard still blocks ambiguity. - A not-found edit rejection now INLINES the file's current content (numbered, <=400 lines) and drops the 'go read it' instruction, so the model repairs the stale anchor in the same turn. Falls back to advising read for huge files. Tests: genuine multi-line fuzzy cases (trailing comma, semicolon) + a doEdit rejection-carries-content test. From the DeepSeek harness feedback; borrowed-ideas #3 (+#2).
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Code Review
This pull request addresses the 'edit-on-autoformat' friction by enhancing the fuzzy line replacement logic to tolerate trailing commas and semicolons, and by inlining the current file content (up to 400 lines) directly into 'not-found' edit rejection messages so the model can repair stale anchors in the same turn. Corresponding unit tests have been added to verify these behaviors. Feedback suggests wrapping the file-reading logic in currentFileView with a try/catch block to gracefully handle unexpected I/O errors and prevent tool execution crashes.
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The edit already failed when we build its rejection; if reading the file to inline its content throws (race, permissions, lock), return null and fall back to advising a read — never crash doEdit.
Drives the actual formatFile (eslint --fix + prettier), not a hand-built string: prettier adds a trailing comma/semicolon, and the model's pre-format anchor still lands via the widened fuzzy matcher instead of rejecting. Institutionalizes the manual verification of the edit-on-autoformat fix.
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Pull request overview
This PR reduces edit friction caused by the write-guard’s post-write auto-formatting (eslint --fix + prettier) by improving stale-anchor recovery: edits are more likely to match after formatting, and failures include enough context to retry without spending an extra turn on read.
Changes:
- Widened
fuzzyLineReplacenormalization to tolerate line-trailing commas/semicolons (common prettier drift). - Enhanced
editnot-found rejections to inline the file’s current content (up to 400 lines) so the model can repair anchors in the same turn. - Added unit + e2e coverage to validate both the widened matcher and the new rejection message behavior.
Reviewed changes
Copilot reviewed 5 out of 5 changed files in this pull request and generated 1 comment.
Show a summary per file
| File | Description |
|---|---|
| packages/core/tests/files-edit.test.ts | Adds focused tests for comma/semicolon-tolerant fuzzy matching and for inlined-content not-found rejections via doEdit. |
| packages/core/tests/edit-autoformat.e2e.test.ts | New e2e test that drives the real formatter (formatFile) and verifies a pre-format anchor still applies post-format. |
| packages/core/src/loop/tools/file-ops.ts | Inlines current file content on edit:not-found to avoid a forced read round-trip; refines not-found help text. |
| packages/core/src/files/edit.ts | Extends fuzzy line normalization to ignore trailing ,/; for formatter drift tolerance. |
| docs/borrowed-ideas.md | Updates the “Borrowed ideas” status note to reflect the new stale-anchor mitigations. |
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It returns read's numbered body WITHOUT the hashline header — by design (it repairs a str_replace edit, which anchors on verbatim text, not a line hash).
…ean write (#60) * feat(write-guard): preventive ACI echo of post-format content on a clean write Roadmap #2 (SWE-agent ACI), preventive half. On a CLEAN write whose content the strip/auto-format pass reshaped, the write-guard now echoes the post-format file (numbered, <=80 lines) so the model's next edit anchors on disk reality instead of the now-stale text it wrote — preventing the stale-anchor not-found that #57 only recovers from. No echo when nothing diverged (token-smart) or for large files (a short re-read note instead). Pure reformatEcho() extracted + unit-tested. * fix(write-guard): trim trailing newline before numbering the echo (Gemini review) A …\n-terminated file produced a phantom empty last line in the numbered echo, which the model could anchor on. Drop the standard trailing newline before split. Test asserts exactly N numbered lines.
From the local DeepSeek model's own UX feedback: its #1 friction is that the write-guard auto-formats a file right after
create/edit(eslint --fix + prettier — the fast feedback it otherwise loves), so the model's nexteditoldStringno longer matches disk →not-found→ a wasted turn spent re-reading the file. Confirmed by the user ("the edit tool fails because the pointer is no longer correct"). Borrowed-ideas #3 (+#2).Two fixes
fuzzyLineReplacealready folds quotes/whitespace/punctuation/Unicode; it now also tolerates a line-trailing comma or semicolon — the classic prettier drift (trailing commas in multiline literals/args; semicolon normalization). More near-miss edits just land. The unique-window guard still blocks any ambiguous match.readthe file, the rejection now includes its current content (numbered, ≤400 lines) — the model fixes the stale anchor in the same turn. Falls back to advisingreadfor huge files.Also refreshed the
not-foundmessage to name the likely cause (auto-reformat: reordered imports, normalized quotes/commas).Tests
doEdittest asserting a not-found rejection carries the file's current content and drops the "go read it" instruction.bun run validategreen (1826 tests).Follow-ups (not here)
createso anchors stay fresh preventively.salvageToolCalls(#3b).test-sibling-requiredon pure-renderer modules;package-exact-depsnoise on throwaway projects.