A Makefile formatter (50 years overdue)

5 hours ago 2

A Python-based Makefile formatter and linter that enforces consistent formatting according to Makefile best practices. It only took 50 years!

🔧 Comprehensive Formatting: Automatically formats Makefiles according to community best practices
📋 Configurable Rules: Customize formatting behavior via ~/.bake.toml
🚦 CI/CD Integration: Check mode for continuous integration pipelines
🔌 Plugin Architecture: Extensible rule system for custom formatting needs
🎨 Beautiful CLI: Rich terminal output with colors and progress indicators
⚡ Fast & Reliable: Written in Python with comprehensive test coverage
✅ Syntax Validation: Ensures Makefiles have correct syntax before and after formatting
🔄 Shell Completion: Auto-completion support for bash, zsh, and fish

mbake applies the following formatting rules:

Tabs for recipes: Ensures all recipe lines use tabs instead of spaces
Assignment operators: Normalizes spacing around :=, =, +=, ?=
Target colons: Consistent spacing around target dependency colons
Trailing whitespace: Removes unnecessary trailing spaces

Backslash normalization: Proper spacing around backslash continuations
Smart joining: Consolidates simple continuations while preserving complex structures

Grouping: Consolidates multiple .PHONY declarations
Auto-detection: Automatically identifies phony targets when .PHONY already exists
Minimal changes: Only modifies .PHONY lines, preserves file structure

Option 1: PyPI (Recommended)

Option 2: VSCode Extension

Open VSCode
Go to Extensions (Ctrl+Shift+X)
Search for "mbake Makefile Formatter"
Click Install

git clone https://github.com/ebodshojaei/mbake.git cd mbake pip install -e .

git clone https://github.com/ebodshojaei/mbake.git cd mbake pip install -e ".[dev]"

mbake uses a subcommand-based CLI structure. All commands support both bake and mbake aliases.

# Check version bake --version # Initialize configuration (optional) bake init # Format a Makefile bake format Makefile # Validate Makefile syntax bake validate Makefile

# Initialize configuration file with defaults bake init # Initialize with custom path or force overwrite bake init --config /path/to/config.toml --force # Show current configuration bake config # Show configuration file path bake config --path # Use custom configuration file bake config --config /path/to/config.toml

# Format a single Makefile bake format Makefile # Format multiple files bake format Makefile src/Makefile tests/*.mk # Check if files need formatting (CI/CD mode) bake format --check Makefile # Show diff of changes without modifying files bake format --diff Makefile # Format with verbose output bake format --verbose Makefile # Create backup before formatting bake format --backup Makefile # Validate syntax after formatting bake format --validate Makefile # Use custom configuration bake format --config /path/to/config.toml Makefile

# Validate single file bake validate Makefile # Validate multiple files bake validate Makefile src/Makefile tests/*.mk # Validate with verbose output bake validate --verbose Makefile # Use custom configuration bake validate --config /path/to/config.toml Makefile

# Install completion for current shell bake --install-completion # Show completion script (for manual installation) bake --show-completion

mbake works with sensible defaults out-of-the-box. Generate a configuration file with:

[formatter] # Indentation settings use_tabs = true tab_width = 4 # Spacing settings space_around_assignment = true space_before_colon = false space_after_colon = true # Line continuation settings normalize_line_continuations = true max_line_length = 120 # PHONY settings group_phony_declarations = true phony_at_top = true # General settings remove_trailing_whitespace = true ensure_final_newline = true normalize_empty_lines = true max_consecutive_empty_lines = 2 # Global settings debug = false verbose = false

# Inconsistent spacing and indentation CC:=gcc CFLAGS= -Wall -g SOURCES=main.c \ utils.c \ helper.c .PHONY: clean all: $(TARGET) $(CC) $(CFLAGS) -o $@ $^ .PHONY: install clean: rm -f *.o

# Clean, consistent formatting CC := gcc CFLAGS = -Wall -g SOURCES = main.c utils.c helper.c .PHONY: all clean install all: $(TARGET) $(CC) $(CFLAGS) -o $@ $^ clean: rm -f *.o

Use mbake in your continuous integration pipelines:

# GitHub Actions example - name: Check Makefile formatting run: | pip install mbake bake format --check Makefile

# Exit codes: # 0 - No formatting needed or formatting successful # 1 - Files need formatting (--check mode) or validation failed # 2 - Error occurred

git clone https://github.com/ebodshojaei/mbake.git cd mbake pip install -e ".[dev]" pre-commit install

# Run all tests pytest # Run with coverage pytest --cov=bake --cov-report=html # Run specific test file pytest tests/test_formatter.py -v

# Format code black bake tests # Lint code ruff check bake tests # Type checking mypy bake

mbake follows a modular, plugin-based architecture:

bake/ ├── __init__.py # Package initialization ├── cli.py # Command-line interface with subcommands ├── config.py # Configuration management ├── core/ │ ├── formatter.py # Main formatting engine │ └── rules/ # Individual formatting rules │ ├── tabs.py # Tab/indentation handling │ ├── spacing.py # Spacing normalization │ ├── continuation.py # Line continuation formatting │ └── phony.py # .PHONY declaration management └── plugins/ └── base.py # Plugin interface

Extend the FormatterPlugin base class:

from bake.plugins.base import FormatterPlugin, FormatResult class MyCustomRule(FormatterPlugin): def __init__(self): super().__init__("my_rule", priority=50) def format(self, lines: List[str], config: dict) -> FormatResult: # Your formatting logic here return FormatResult( lines=modified_lines, changed=True, errors=[], warnings=[] )

Contributions are welcome! Please read our Contributing Guide for details on:

Code of conduct
Development process
Submitting pull requests
Reporting issues

Quick Start for Contributors

Fork the repository
Create a feature branch (git checkout -b feature/amazing-feature)
Make your changes
Add tests for new functionality
Run the test suite (pytest)
Commit your changes (git commit -m 'Add amazing feature')
Push to the branch (git push origin feature/amazing-feature)
Open a Pull Request

This project is licensed under the MIT License - see the LICENSE file for details.

✅ Core formatting engine (100% test coverage)
✅ Configuration system
✅ Command-line interface with subcommands
✅ Plugin architecture
✅ Assignment spacing normalization
✅ Tab indentation handling
✅ Whitespace management
✅ Line continuation formatting
✅ Makefile syntax validation
✅ Shell completion support
✅ CI/CD integration
🚧 Advanced rule customization
🚧 IDE integrations

Minimal changes: Only modify what needs to be fixed, preserve file structure
Predictable behavior: Consistent formatting rules across all Makefiles
Fast execution: Efficient processing of large Makefiles
Reliable validation: Ensure formatted Makefiles have correct syntax
Developer-friendly: Rich CLI with helpful error messages and progress indicators

This approach ensures a reliable, maintainable formatter that handles common Makefile formatting needs while preserving the structure and functionality of your build files.

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