analyzing-git-sessions

# Analyzing Git Sessions ## Core Responsibility Generate structured analysis of git activity for specified timeframe or commit range, including commit history, file changes, statistics, and optional diffs. ## Inputs Accept from user: - **Time range**: "last 2 hours", "since 10am", "today", "since 2025-10-23 14:00" - **Commit range**: "abc123..def456", "HEAD~5..HEAD", "feature-branch..main" - **Optional filters**: Specific paths, authors, or file types - **Output depth**: Concise (default), Detailed, or Code Review format ## Working Process ### Step 1: Parse and Validate Input 1. **Determine range type**: - Time-based: Parse relative or absolute time - Commit-based: Validate commit references exist - Branch-based: Resolve branch names to commits 2. **Validate git repository**: ```bash git rev-parse --git-dir ``` 3. **Check range has commits**: ```bash git log <range> --oneline | head -1 ``` If empty, inform user and exit. ### Step 2: Extract Commit History ```bash # Get all commits in range git log <range> --oneline --no-decorate # Get detailed commit info git log <range> --format="%h|%an|%ar|%s" --no-decorate # Count commits git log <range> --oneline | wc -l ``` Store commit data for summary. ### Step 3: Generate Statistics **Overall change statistics**: ```bash # Summary stats (insertions/deletions by file) git diff <start>..<end> --stat # Numeric stats for parsing git diff <start>..<end> --numstat # Count total changes git diff <start>..<end> --shortstat ``` **Author breakdown** (if multiple authors): ```bash git shortlog <start>..<end> -sn ``` **File categorization**: - Identify new files (show in status "A") - Identify deleted files (show in status "D") - Identify renamed files (show in status "R") - Modified files with change magnitude ### Step 4: Identify Key Files for Detailed Analysis **Prioritization rules**: 1. **Large changes** (>100 lines modified): Always include 2. **New files**: Include (especially if >50 lines) 3. **Deleted files**: Note but don't diff 4. **Architecture files**: `build.gradle.kts`, `AndroidManifest.xml`, module configs 5. **Test files**: Flag separately for test coverage assessment **Extract key file list**: ```bash # Files changed with line counts git diff <start>..<end> --numstat | sort -rn -k1 -k2 ``` Limit to top 10 files by default to avoid context overflow. ### Step 5: Generate Selective Diffs (Based on Depth) **Concise mode**: No diffs, stats only **Detailed mode**: Diffs for top 3-5 key files ```bash git diff <start>..<end> -- path/to/key/file.kt ``` **Code Review mode**: Diffs for all modified files, grouped by module ```bash # Group by directory git diff <start>..<end> --name-only | cut -d'/' -f1-2 | sort -u # Generate diffs per module for module in modules; do git diff <start>..<end> -- $module/ done ``` **Context overflow protection**: - If >10 files changed significantly, limit to top 5 diffs - Warn user: "Showing top 5 files by change size. Request specific files for full diffs." ### Step 6: Present Structured Summary **Format based on depth**: #### Concise Summary ```markdown ## Git Session Summary **Range**: <start-commit> to <end-commit> (<timeframe>) **Commits**: X commits by Y author(s) **Files Changed**: A modified, B added, C deleted **Net Changes**: +X -Y lines ### Commits - abc123 Commit message 1 - def456 Commit message 2 ... ### Top Files Changed 1. path/to/file1.kt (+50 -20) 2. path/to/file2.kt (+30 -15) ... ``` #### Detailed Summary Includes: - Full commit list with authors and timestamps - Complete file list with change stats - Author breakdown - Top 3-5 diffs for review #### Code Review Format ```markdown ## Code Review Summary ### Overview - **PR Title**: [Suggested from commit messages] - **Changes**: X files across Y modules - **Scope**: [Inferred from changed files] ### Commits [Formatted commit list suitable for PR description] ### Changes by Module **Module: app** - file1.kt: Description of changes - file2.kt: Description of changes **Module: core** ... ### Key Changes [Diffs for significant modifications] ### Test Coverage - Test files modified: X - New tests added: ~Y ``` ## Output Guidelines ### Commit Messages - Show short hash (7 chars) - Show first line of commit message only - Truncate long messages to 80 chars - Group by author if multiple contributors ### File Paths - Use relative paths from repo root - Format as code: `path/to/file.kt` - Include line change magnitude: (+X -Y) - Highlight file type (source, test, config) ### Statistics Present in clear tables: ```markdown | Metric | Count | | ------------- | ----- | | Commits | 15 | | Files Changed | 23 | | Insertions | +450 | | Deletions | -180 | ``` ### Diffs - Include file path as header: `### path/to/file.kt` - Use code blocks with syntax highlighting - Show context lines (git default: 3 lines before/after) - Truncate very large diffs (>200 lines) with summary ## Context Budget Management **Monitor diff sizes**: - Small session (<10 files, <500 lines): Safe for detailed mode - Medium session (10-30 files, 500-2000 lines): Use selective diffs - Large session (>30 files, >2000 lines): Concise mode with warnings **Progressive disclosure**: 1. Always start with concise summary 2. Ask user: "Would you like detailed diffs for specific files?" 3. Generate diffs on demand rather than upfront **Fallback for large sessions**: "This session modified 45 files with 5000+ line changes. Showing concise summary. Request specific files or modules for detailed diffs." ## Anti-Patterns to Avoid **Don't**: - Generate diffs for all files in large sessions (context overflow) - Include full diffs without asking (waste context on unneeded details) - Ignore file types (treat test changes same as source changes) - Lose context on what user wants to know - Use generic summaries ("modified 10 files") without specifics **Do**: - Ask user what level of detail they need - Prioritize key files by change magnitude - Categorize files (source, test, config, docs) - Provide actionable summaries - Offer to drill down on specific files ## Success Criteria A good git session analysis should: 1. **Inform**: User understands scope of changes at a glance 2. **Focus**: Highlights most significant changes first 3. **Actionable**: Provides paths and diffs for deeper review 4. **Efficient**: Doesn't waste context on unnecessary details 5. **Adaptable**: Adjusts depth based on session size and user needs ## Example Outputs See `contexts/example-outputs.md` for detailed examples of concise summaries and code review formats.