Uncomment: Tree-sitter Based Comment Removal Tool

A fast, accurate, and extensible comment removal tool that uses tree-sitter for parsing, ensuring 100% accuracy in comment identification. Originally created to clean up AI-generated code with excessive comments, it now supports any language with a tree-sitter grammar through its flexible configuration system.

Support This Project

If you find uncomment helpful, please consider sponsoring the development:

Your support helps maintain and improve this tool for the community! 🚀

Features

• 100% Accurate: Uses tree-sitter AST parsing to correctly identify comments
• No False Positives: Never removes comment-like content from strings
• Smart Preservation: Keeps important metadata, TODOs, FIXMEs, and language-specific patterns
• Parallel Processing: Multi-threaded processing for improved performance
• Extensible: Support any language with tree-sitter grammar through configuration
• Dynamic Grammar Loading: Load grammars from Git, local paths, or pre-compiled libraries
• Configuration System: TOML-based configuration for project-specific settings
• Smart Init Command: Automatically generate configuration based on your project
• Fast: Leverages tree-sitter's optimized parsing
• Safe: Dry-run mode to preview changes
• Built-in Benchmarking: Performance analysis and profiling tools

Supported Languages

Built-in Languages

• Python (.py, .pyw, .pyi, .pyx, .pxd)
• JavaScript (.js, .jsx, .mjs, .cjs)
• TypeScript (.ts, .tsx, .mts, .cts, .d.ts, .d.mts, .d.cts)
• Rust (.rs)
• Go (.go)
• Java (.java)
• C (.c, .h)
• C++ (.cpp, .cc, .cxx, .hpp, .hxx)
• Ruby (.rb, .rake, .gemspec)
• YAML (.yml, .yaml)
• HCL/Terraform (.hcl, .tf, .tfvars)
• Makefile (Makefile, .mk)
• Shell/Bash (.sh, .bash, .zsh, .bashrc, .zshrc)
• Haskell (.hs, .lhs)
• JSON with Comments (.jsonc)

Extensible to Any Language

Through the configuration system, you can add support for any language with a tree-sitter grammar, including:

• Vue, Svelte, Astro (Web frameworks)
• Swift, Kotlin, Dart (Mobile development)
• Zig, Nim (Systems programming)
• Elixir, Clojure, Julia (Functional/Scientific)
• And many more...

Installation

Via Package Managers

Homebrew (macOS/Linux)

brew tap goldziher/tap
brew install uncomment

Cargo (Rust)

cargo install uncomment

npm (Node.js)

npm install -g uncomment-cli

pip (Python)

pip install uncomment

From source

git clone https://github.com/Goldziher/uncomment.git
cd uncomment
cargo install --path .

Requirements

• For building from source: Rust 1.70+
• For npm/pip packages: Pre-built binaries are downloaded automatically

Quick Start

Run Without Installing

npx -y uncomment-cli@latest .
uvx uncomment .

Add --dry-run to either command to preview changes before writing.

Install Locally

# Generate a configuration file for your project
uncomment init

# Remove comments from files
uncomment src/

# Preview changes without modifying files
uncomment --dry-run src/

Usage

Configuration

# Generate a smart configuration based on your project
uncomment init

# Generate a comprehensive configuration with all supported languages
uncomment init --comprehensive

# Interactive configuration setup
uncomment init --interactive

# Use a custom configuration file
uncomment --config my-config.toml src/

Init Command Examples

The init command intelligently detects languages in your project:

# Smart detection - analyzes your project and includes only detected languages
$ uncomment init
Detected languages in your project:
- 150 rust files
- 89 typescript files
- 45 python files
- 12 vue files (requires custom grammar)
- 8 dockerfile files (requires custom grammar)

Generated .uncommentrc.toml with configurations for detected languages.

# Comprehensive mode - includes configurations for 25+ languages
$ uncomment init --comprehensive
Generated comprehensive configuration with all supported languages.

# Specify output location
$ uncomment init --output config/uncomment.toml

# Force overwrite existing configuration
$ uncomment init --force

Basic Usage

# Remove comments from a single file
uncomment file.py

# Preview changes without modifying files
uncomment --dry-run file.py

# Process multiple files
uncomment src/*.py

# Remove documentation comments/docstrings
uncomment --remove-doc file.py

# Remove TODO and FIXME comments
uncomment --remove-todo --remove-fixme file.py

# Add custom patterns to preserve
uncomment --ignore-patterns "HACK" --ignore-patterns "WARNING" file.py

# Process entire directory recursively
uncomment src/

# Use parallel processing with 8 threads
uncomment --threads 8 src/

Optional Benchmarking Tools

The crate ships development binaries for benchmarking and profiling, but they are gated behind the bench-tools feature so they are not installed for regular users.

• Install from crates.io with the extras:

  cargo install uncomment --features bench-tools
  

• Run locally without installing:

  cargo run --release --features bench-tools --bin benchmark -- --target /path/to/repo --iterations 3
  cargo run --release --features bench-tools --bin profile -- /path/to/repo
  

Contributing

See CONTRIBUTING.md for local development, automation hooks, and release procedures.

Default Preservation Rules

Always Preserved

• Comments containing ~keep
• TODO comments (unless --remove-todo)
• FIXME comments (unless --remove-fixme)
• Documentation comments (unless --remove-doc)

Linting Tool Directives (Always Preserved)

The tool preserves all linting and formatting directives to ensure your CI/CD pipelines and development workflows remain intact:

Go:

• //nolint, //nolint:gosec, //golangci-lint, //staticcheck, //go:generate

Python:

• # noqa, # type: ignore, # mypy:, # pyright:, # ruff:, # pylint:, # flake8:
• # fmt: off/on, # black:, # isort:, # bandit:, # pyre-ignore

JavaScript/TypeScript:

• ESLint: eslint-disable, eslint-enable, eslint-disable-next-line
• TypeScript: @ts-ignore, @ts-expect-error, @ts-nocheck, @ts-check
• Triple-slash: /// <reference, /// <amd-module, /// <amd-dependency
• Formatters: prettier-ignore, biome-ignore, deno-lint-ignore
• Coverage: v8 ignore, c8 ignore, istanbul ignore

Rust:

• Attributes: #[allow], #[deny], #[warn], #[forbid], #[cfg]
• Clippy: clippy::, #[rustfmt::skip]

Java:

• @SuppressWarnings, @SuppressFBWarnings, //noinspection, // checkstyle:

C/C++:

• // NOLINT, // NOLINTNEXTLINE, #pragma, // clang-format off/on

Shell/Bash:

• # shellcheck disable, # hadolint ignore

YAML:

• # yamllint disable/enable

HCL/Terraform:

• # tfsec:ignore, # checkov:skip, # trivy:ignore, # tflint-ignore

Ruby:

• # rubocop:disable/enable, # reek:, # standard:disable/enable

Configuration

Uncomment uses a flexible TOML-based configuration system that allows you to customize behavior for your project.

Configuration File Discovery

Uncomment searches for configuration files in the following order:

1. Command-line specified config: --config path/to/config.toml
2. .uncommentrc.toml in the current directory
3. .uncommentrc.toml in parent directories (up to git root or filesystem root)
4. ~/.config/uncomment/config.toml (global configuration)
5. Built-in defaults

Basic Configuration Example

[global]
remove_todos = false
remove_fixme = false
remove_docs = false
preserve_patterns = ["IMPORTANT", "NOTE", "WARNING"]
use_default_ignores = true
respect_gitignore = true

[languages.python]
extensions = ["py", "pyw", "pyi"]
preserve_patterns = ["noqa", "type:", "pragma:", "pylint:"]

[patterns."tests/**/*.py"]
# Keep all comments in test files
remove_todos = false
remove_fixme = false
remove_docs = false

Dynamic Grammar Loading

You can extend support to any language with a tree-sitter grammar:

# Add Swift support via Git
[languages.swift]
name = "Swift"
extensions = ["swift"]
comment_nodes = ["comment", "multiline_comment"]
preserve_patterns = ["MARK:", "TODO:", "FIXME:", "swiftlint:"]

[languages.swift.grammar]
source = { type = "git", url = "https://github.com/alex-pinkus/tree-sitter-swift", branch = "main" }

# Use a local grammar
[languages.custom]
name = "Custom Language"
extensions = ["custom"]
comment_nodes = ["comment"]

[languages.custom.grammar]
source = { type = "local", path = "/path/to/tree-sitter-custom" }

# Use a pre-compiled library
[languages.proprietary]
name = "Proprietary Language"
extensions = ["prop"]
comment_nodes = ["comment"]

[languages.proprietary.grammar]
source = { type = "library", path = "/usr/local/lib/libtree-sitter-proprietary.so" }

Configuration Merging

When multiple configuration files are found, they are merged with the following precedence (highest to lowest):

1. Command-line flags
2. Local .uncommentrc.toml files (closer to the file being processed wins)
3. Global configuration (~/.config/uncomment/config.toml)
4. Built-in defaults

Pattern-specific configurations override language configurations for matching files.

How It Works

Unlike regex-based tools, uncomment uses tree-sitter to build a proper Abstract Syntax Tree (AST) of your code. This means it understands the difference between:

• Real comments vs comment-like content in strings
• Documentation comments vs regular comments
• Inline comments vs standalone comments
• Language-specific metadata that should be preserved

Architecture

The tool is built with a modular, extensible architecture:

1. Language Registry: Manages both built-in and dynamically loaded languages
2. Grammar Manager: Handles loading grammars from Git, local paths, or compiled libraries
3. Configuration System: TOML-based hierarchical configuration with merging
4. AST Visitor: Traverses the tree-sitter AST to find comments
5. Preservation Engine: Applies rules to determine what to keep
6. Output Generator: Produces clean code with comments removed

Key Components

• Dynamic Grammar Loading: Automatically downloads and compiles tree-sitter grammars
• Grammar Caching: Caches compiled grammars for performance
• Configuration Discovery: Searches for configs in project hierarchy
• Pattern Matching: File-pattern-specific configuration overrides

Adding New Languages

With the new configuration system, you can add languages without modifying code:

Method 1: Using Configuration (Recommended)

Add to your .uncommentrc.toml:

[languages.mylang]
name = "My Language"
extensions = ["ml", "mli"]
comment_nodes = ["comment"]
preserve_patterns = ["TODO", "FIXME"]

[languages.mylang.grammar]
source = { type = "git", url = "https://github.com/tree-sitter/tree-sitter-mylang", branch = "main" }

Method 2: Built-in Support

For frequently used languages:

1. Add the tree-sitter parser dependency to Cargo.toml
2. Register the language in src/grammar/mod.rs
3. Add language configuration in src/languages/registry.rs

Git Hooks

Pre-commit

Add to your .pre-commit-config.yaml:

repos:
  - repo: https://github.com/Goldziher/uncomment
    rev: v2.5.0
    hooks:
      - id: uncomment

Lefthook

Add to your lefthook.yml:

pre-commit:
  commands:
    uncomment:
      run: uncomment {staged_files}
      stage_fixed: true

For both hooks, install uncomment via pip:

pip install uncomment

Performance

While slightly slower than regex-based approaches due to parsing overhead, the tool is very fast and scales well with parallel processing:

Single-threaded Performance

• Small files (<1000 lines): ~20-30ms
• Large files (>10000 lines): ~100-200ms

Parallel Processing Benchmarks

Performance scales excellently with multiple threads:

Thread Count	Files/Second	Speedup
1 thread	1,500	1.0x
4 threads	3,900	2.6x
8 threads	5,100	3.4x

Benchmarks run on a large enterprise codebase with 5,000 mixed language files

Built-in Benchmarking

Use the built-in tools to measure performance on your specific codebase:

# Basic benchmark
uncomment benchmark --target /path/to/repo

# Detailed benchmark with multiple iterations
uncomment benchmark --target /path/to/repo --iterations 5 --threads 8

# Memory and performance profiling
uncomment profile /path/to/repo

The accuracy gained through AST parsing is worth the small performance cost, and parallel processing makes it suitable for even the largest codebases.

Development

Project Structure

uncomment/
├── src/               # Source code
├── tests/             # Integration tests
├── fixtures/          # Test fixtures
│   ├── languages/     # Language-specific test files
│   └── repos/         # Repository test configurations
├── bench/             # CLI benchmarking tool
├── benchmarks/        # Rust micro-benchmarks
├── test-repos/        # Manual testing scripts
└── scripts/           # Build and release scripts

Benchmarking

The project includes two types of benchmarking tools:

• bench/: Custom CLI benchmarking tool for testing real-world performance on large codebases. Use via cargo run --release --bin benchmark.
• benchmarks/: Standard Rust micro-benchmarks for testing specific functions and components. Run with cargo bench.

Testing

# Run all tests
cargo test

# Run tests with output
cargo test -- --nocapture

# Run integration tests (including network-dependent)
cargo test -- --ignored

License

MIT