Refactor duplicate JSON/JSONL parsing logic into shared utility

[Copilot]

Both parse_claude_log.cjs and parse_copilot_log.cjs contained ~50 lines of identical JSON/JSONL parsing fallback logic, creating maintenance burden and divergence risk.

Changes

• New shared function: Created parseLogEntries() in log_parser_shared.cjs to handle JSON array, JSONL, and mixed format parsing with debug logs
• parse_claude_log.cjs: Removed 47 lines of duplicate parsing code, replaced with shared function call
• parse_copilot_log.cjs: Removed 38 lines of duplicate parsing code, replaced with shared function call
• Test coverage: Added 11 unit tests covering all format variations and edge cases

Example

Before (duplicated in both parsers):

// First, try to parse as JSON array
try {
  logEntries = JSON.parse(logContent);
  if (!Array.isArray(logEntries)) throw new Error("Not a JSON array");
} catch (jsonArrayError) {
  // Try JSONL format - 40+ lines of identical parsing logic...
  logEntries = [];
  const lines = logContent.split("\n");
  for (const line of lines) {
    const trimmedLine = line.trim();
    // ... more parsing logic
  }
}

After:

const logEntries = parseLogEntries(logContent);
if (!logEntries) {
  return { markdown: "Log format not recognized...", mcpFailures: [], maxTurnsHit: false };
}

Net reduction: 85 lines of duplicate code eliminated.

Original prompt

---

This section details on the original issue you should resolve

<issue_title>[duplicate-code] Duplicate Code: JSON/JSONL Parsing Fallback in Log Parsers</issue_title>
<issue_description># 🔍 Duplicate Code Detected: Log Parser JSON Fallback

Analysis of commit 102022d

Assignee: @copilot

Summary

Both Copilot and Claude log parsers reimplement the same JSON/JSONL parsing fallback logic, even down to identical trimming, array-handling, and line-by-line parsing. This block is ~50 lines long in each file and differs only by parser name, making it easy for the parsers to drift out of sync when formats change.

Duplication Details

Pattern: JSON/JSONL parsing fallback

• Severity: Medium
• Occurrences: 2
• Locations:
  • pkg/workflow/js/parse_claude_log.cjs (lines 31-89)
  • pkg/workflow/js/parse_copilot_log.cjs (lines 60-118)
• Code Sample:

  try {
    logEntries = JSON.parse(logContent);
    if (!Array.isArray(logEntries)) {
      throw new Error("Not a JSON array");
    }
  } catch (jsonArrayError) {
    logEntries = [];
    const lines = logContent.split("\n");
    for (const line of lines) {
      const trimmedLine = line.trim();
      if (trimmedLine === "") continue;
      if (trimmedLine.startsWith("[{")) {
        // try to parse array
      }
      if (!trimmedLine.startsWith("{")) continue;
      try {
        const jsonEntry = JSON.parse(trimmedLine);
        logEntries.push(jsonEntry);
      } catch (jsonLineError) {
        continue;
      }
    }
  }

Impact Analysis

• Maintainability: Updating parsing behavior (e.g., new log format or stricter validation) requires editing both files, inviting divergence.
• Bug Risk: Fixes applied to one parser (Copilot or Claude) may be missed in the other, leading to inconsistent user-facing summaries for the same log format.
• Code Bloat: ~100 duplicated lines increase file size and noise.

Refactoring Recommendations

1. Extract shared parser helper
   • Create a utility in log_parser_shared.cjs (e.g., parseLogEntries(logContent, options)) that encapsulates the JSON array → JSONL fallback.
   • Estimated effort: 2-3 hours. Benefits: single source of truth, easier future format tweaks.
2. Inject parser-specific hooks
   • Allow callers to supply parser-specific behaviors (e.g., Copilot’s debug log handling) through options callbacks instead of duplicating the base logic.

Implementation Checklist

• Review duplication findings
• Prioritize refactoring tasks
• Create refactoring plan
• Implement changes
• Update tests
• Verify no functionality broken

Analysis Metadata

• Analyzed Files: 4
• Detection Method: Serena semantic code analysis
• Commit: 102022d
• Analysis Date: 2024-06-05

AI generated by Duplicate Code Detector</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes [duplicate-code] Duplicate Code: JSON/JSONL Parsing Fallback in Log Parsers #4571

---

💡 You can make Copilot smarter by setting up custom instructions, customizing its development environment and configuring Model Context Protocol (MCP) servers. Learn more Copilot coding agent tips in the docs.

[github-actions]

✅ Agentic Changeset Generator completed successfully.

[Copilot]

Pull request overview

This PR successfully refactors duplicate JSON/JSONL parsing logic from two log parser files into a shared utility function, eliminating 85 lines of duplicate code while maintaining functionality and adding comprehensive test coverage.

Key Changes

• Created shared utility: New parseLogEntries() function in log_parser_shared.cjs handles JSON array, JSONL, and mixed format parsing with consistent error handling
• Refactored parsers: Both parse_claude_log.cjs and parse_copilot_log.cjs now use the shared function, reducing code duplication
• Comprehensive testing: Added 11 unit tests covering JSON arrays, JSONL, mixed formats, edge cases, and error conditions

Reviewed changes

Copilot reviewed 84 out of 84 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
pkg/workflow/js/log_parser_shared.cjs	Added parseLogEntries() function with robust JSON/JSONL parsing logic that returns null on failure
pkg/workflow/js/parse_claude_log.cjs	Removed 47 lines of duplicate parsing code, replaced with shared function call
pkg/workflow/js/parse_copilot_log.cjs	Removed 38 lines of duplicate parsing code, replaced with shared function call
pkg/workflow/js/log_parser_shared.test.cjs	Added 11 comprehensive test cases covering all parsing scenarios
.github/workflows/*.lock.yml	Bundled workflow files updated with inlined shared function across 60+ workflows

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.