C++ Code Formatter

C++ Code Formatter

Purpose

This skill helps format Sanmill's C++ code to ensure code style consistency and maintainability across the codebase.

Use Cases

• Format C++ code after modifications
• Check code style compliance
• Format code before committing
• Batch format project C++ files
• Validate code style in CI/CD pipelines

Quick Commands

Using Project Script (Recommended)

# Format all C++ and Dart code (will auto-commit)
./format.sh

# Format without auto-commit
./format.sh s

The script formats:

• All .h and .cpp files in src/, include/, tests/
• All Dart files in the project
• Uses project's .clang-format configuration

Manual Formatting

# Format single file
clang-format -i src/position.cpp

# Format multiple files
clang-format -i src/*.cpp src/*.h

# Check without modifying (dry-run)
clang-format --dry-run --Werror src/position.cpp

Configuration

Project Configuration Files

• .clang-format - C++ formatting rules (project root)
• CPPLINT.cfg - Code style checking rules
• .editorconfig - Editor-specific settings

View Current Configuration

cat .clang-format

Code Style Checking

# Check specific file with cpplint
cpplint --config=CPPLINT.cfg src/position.cpp

# The configuration file defines which checks to enable/disable

Git Integration

Pre-commit Workflow

# 1. Make code changes
# 2. Format code
./format.sh s

# 3. Review changes
git diff

# 4. If correct, commit
git add .
git commit -m "Your commit message"

Format Only Staged Files

git diff --cached --name-only --diff-filter=ACM | \
grep -E '\.(cpp|h|cc|hpp)$' | \
xargs clang-format -i

Common Issues & Solutions

1. Format Breaks Code Structure

• Check: Verify .clang-format configuration
• Check: Ensure clang-format version matches team standard
• Workaround: Use // clang-format off and // clang-format on for special blocks

2. Batch Formatting Creates Large Changes

• Solution: Format in batches and commit separately
• Label: Use clear commit message like "style: Format C++ code"
• Communicate: Notify team members to sync

3. Format Conflicts Between Developers

• Ensure: All use same .clang-format file
• Ensure: All use same clang-format version
• Establish: Team formatting conventions

Best Practices

1. Format frequently: Format after each significant change
2. Format before commits: Always format before committing
3. Review formatting changes: Don't blindly commit formatting
4. Use project script: Prefer ./format.sh over manual commands
5. Separate formatting commits: Keep formatting separate from logic changes
6. Don't hand-edit formatting: Let tools do the work

Tools Required

clang-format

# Check if installed
clang-format --version

# Install on Ubuntu/Debian
sudo apt-get install clang-format

# Install on macOS
brew install clang-format

cpplint (Optional)

For additional style checking beyond formatting.

Output Format

Formatting operations should report:

• ✓ Files formatted successfully
• ⚠ Files with style violations
• ✗ Files that failed to format
• 📊 Total files processed
• 💡 Style improvement recommendations

Reference Resources

• Configuration: .clang-format, CPPLINT.cfg, .editorconfig (project root)
• Format script: format.sh (project root)
• clang-format docs: https://clang.llvm.org/docs/ClangFormat.html
• C++ source locations: src/, include/, tests/