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Claude-Code-Workflow/ccw/WRITE_FILE_FIX_SUMMARY.md
catlog22 154a9283b5 Add internationalization support for help view and implement help rendering logic
- Introduced `help-i18n.js` for managing translations in Chinese and English for the help view.
- Created `help.js` to render the help view, including command categories, workflow diagrams, and CodexLens quick-start.
- Implemented search functionality with debounce for command filtering.
- Added workflow diagram rendering with Cytoscape.js integration.
- Developed tests for write-file verification, ensuring proper handling of small and large JSON files.
2025-12-16 22:24:29 +08:00

2.5 KiB

Write File Verification Enhancement

Problem

ccw/src/tools/write-file.ts would return success messages claiming files were created, but in some cases (especially with long JSON files), the files were not actually written to disk.

Root Cause

The write operation used writeFileSync() but did not verify that the file was successfully created afterward. In edge cases (file system issues, permission problems, disk space, etc.), the write could fail silently without proper error detection.

Solution

Added comprehensive post-write verification in three layers:

1. File Existence Check

if (!existsSync(filePath)) {
  return `File verification failed: file does not exist at ${filePath}`;
}

2. File Size Verification

const stats = statSync(filePath);
if (stats.size !== expectedBytes) {
  return `File verification failed: size mismatch (expected ${expectedBytes}B, actual ${stats.size}B)`;
}

3. Content Read-Back Verification

const readContent = readFileSync(filePath, { encoding });
const actualBytes = Buffer.byteLength(readContent, encoding);
if (actualBytes !== expectedBytes) {
  return `File verification failed: content size mismatch after read`;
}

Changes Made

File: ccw/src/tools/write-file.ts

  1. Added import: statSync from 'fs' (line 13)
  2. Added function: verifyFileWrite() (lines 69-100) - Three-layer verification
  3. Modified handler: Added verification call after write (lines 188-195)
  4. Enhanced messages: All success messages now include "- verified" suffix

Test Coverage: ccw/tests/write-file-verification.test.js

Created comprehensive test suite covering:

  • Small file writes
  • Large JSON files (>100KB)
  • Very large JSON files (>1MB)
  • Verification failure detection
  • Multiple encoding support

Test Results

tests 5
pass 5
fail 0

Test execution times:
- Small file: 3.7ms
- Large JSON (>100KB): 46.8ms
- Very large JSON (>1MB): 119ms

Benefits

  1. Reliability: Files are guaranteed to exist and be complete
  2. Error Detection: Catches silent write failures immediately
  3. Debugging: Clear error messages indicate exact failure point
  4. Long JSON Safety: Special protection for large file writes
  5. User Trust: "verified" suffix confirms write success

Backward Compatibility

Fully backward compatible - all existing functionality preserved Only adds verification step, no breaking changes Minimal performance impact (ms range even for MB files)