- Removed insertBefore and substr hashline edit operations, simplifying the edit API to support only replaceLine, replaceLines, and insertAfter operations.
- Updated hashline edit schema and type definitions to remove insertBefore and substr operation types from the ParsedRefs union and edit validation logic.
- Removed insertBefore and substr test cases from hashline test suite, including tests for insert-before functionality, anchor echo stripping, and substring matching.
- Updated benchmark runner to refactor edit operations from src/dst format to discriminated union types (replaceLine, replaceLines, insertAfter) and adjusted insertAfter line references.
- Redesigned hashline edit API to use discriminated union variants (replaceLine, replaceLines, insertAfter, insertBefore, substr) instead of nested src/dst structure.
- Changed hash algorithm from xxHash64 hex to xxHash32 base36 encoding and increased hash length from 2 to 3 characters.
- Added substr edit variant to match and replace content by unique substring when line hashes are unavailable.
- Implemented line relocation heuristics to resolve stale line references when hash uniquely identifies a moved line.
- Moved substr needle search from edit application phase to pre-validation phase for earlier error detection.
- Migrated hashline edit type definitions from manual TypeScript interfaces to schema-derived types using Static<typeof schema> pattern.
- Added `substr` source specification kind to match and replace lines by unique substring without requiring line-hash references.
- Implemented substring matching logic in hashline edits with validation for uniqueness and error handling for not-found and ambiguous cases.
- Added schema definition and type guards for the new `substr` operation type across patch system.
- Added mutation preview hints to error messages when edits fail with 'No changes made' errors, showing line numbers, hashes, and added/removed lines.
- Changed formatter to pin JavaScript fixtures to the flow parser to avoid parser-dependent formatting drift.
- Added whitespace preservation logic to treat whitespace-only differences as passing in file verification.
- Removed substring source specification kind from hashline edits, requiring users to use line-hash references instead.
- Simplified SrcSpec type to use generic type parameter for line references, removing substring variant from union.
- Updated react-edit-benchmark to use --max-tasks option for deterministic task sampling and changed default batch sizes to 1.
- Added streaming functions `streamHashLinesFromUtf8` and `streamHashLinesFromLines` for processing large files with configurable chunking.
- Added `HashlineStreamOptions` interface to control streaming behavior with `startLine`, `maxChunkLines`, and `maxChunkBytes` options.
- Changed hashline format from 4-character to 2-character hex hashes for more compact output.
- Updated `computeLineHash` function to normalize whitespace and removed line number from hash seed for consistency.
- Improved CLI argument parsing with explicit handling of `--help`, `--version`, and subcommand detection.
- Removed `@types/diff` dev dependency as it is no longer needed.
- Changed `HashlineEdit.src` from string format (e.g., `"5:ab"`, `"5:ab..9:ef"`) to structured `SrcSpec` object with discriminated union types (`{ kind: "single", ref: "..." }`, `{ kind: "range", start: "...", end: "..." }`, `{ kind: "insertAfter", after: "..." }`, `{ kind: "insertBefore", before: "..." }`, `{ kind: "substring", needle: "..." }`).
- Refactored `parseSrc` function to `parseSrcSpec` to handle structured `SrcSpec` objects instead of string parsing, replacing string validation and delimiter parsing logic with explicit case handling for each operation kind.
- Updated tool schema in `index.ts` to define `srcSpecSchema` as a discriminated union type with five variants, replacing the previous simple string-based `src` parameter definition.
- Added substring-based source matching for hashline edits to support matching lines by content when hash references are unavailable.
- Added automatic detection and repair of single-line merges where models incorrectly combine multiple lines into one.
- Added normalization of Unicode-confusable hyphens to ASCII hyphens to handle model-generated variations.
- Added heuristics to restore indentation and preserve wrapped line formatting during edits.
- Relaxed comma validation in src to allow commas while rejecting inputs with multiple line references.
- Enhanced parseLineRef to accept shorter hash prefixes instead of requiring exact hash matches.
- Improved error messages for hash mismatches to provide more actionable guidance.
- Replaced HashlineEdit API from old/new/after fields to src/dst fields with unified range syntax supporting single lines, ranges, insert-after, and insert-before operations.
- Added parseSrc() function to parse structured line references from src strings supporting formats like '5:ab', '5:ab..9:ef', '5:ab..', and '..5:ab'.
- Added heuristics to strip anchor line echoes and range boundary echoes from model-generated replacement content.
- Implemented preserveWhitespaceOnlyLinesLoose() for improved whitespace preservation using loose matching strategy when replacement line counts don't match.
- Added comprehensive benchmark reports for Claude Sonnet 4.5, Gemini 2.5 Flash Lite, and GPT-5.1 Codex Mini models evaluating hashline edit performance across 60 tasks.
- Added `toArray()` helper function to normalize `string | string[]` inputs for hashline edit operations with comma-separated line reference support.
- Added `HashlineMismatchError` class that displays grep-style output with `>>>` markers for hash validation failures.
- Added `HashMismatch` type for representing individual hash mismatches with line number, expected hash, and actual hash.
- Updated `HashlineEdit` type to accept `string | string[]` for `old` and `new` fields, allowing both singular and plural input formats.
- Reduced hash length from 4 to 2 hex characters (16-bit hashes) for more concise line references.
- Enhanced `parseLineRef()` to strip display-format suffixes and `validateLineRef()` to throw `HashlineMismatchError` with context lines for better error reporting.
- Added HashlineMismatchError class with formatted error messages showing mismatched hashes with context lines.
- Added HashMismatch type to represent hash validation errors with line number, expected, and actual hash values.
- Enhanced hash validation in applyHashlineEdits to collect all hash mismatches before applying edits instead of failing on first mismatch.
- Renamed HashlineEdit fields from 'src'/'dst' to 'old'/'new' for improved naming clarity and consistency.
- Added hashline edit mode for line-addressed edits using hash-verified line references with xxHash64 integrity verification.
- Replaced `edit.patchMode` boolean setting with `edit.mode` enum supporting 'replace', 'patch', and 'hashline' modes.
- Added `readHashLines` configuration setting to include line hashes in read output for hashline edit mode.
- Implemented `computeLineHash`, `formatHashLines`, `parseLineRef`, `validateLineRef`, and `applyHashlineEdits` utility functions for hashline operations.
- Updated read tool to support optional `hashes` parameter and prioritize hash lines over line numbers when both are requested.
- Changed `getEditModelVariants()` return type from `Record<string, 'patch' | 'replace'>` to `Record<string, EditMode | null>` and removed hardcoded model-specific defaults.
can1357