A command-line tool to analyze Swift code complexity and quality metrics using swift-syntax.

• Multiple Complexity Metrics: Supports cyclomatic and cognitive complexity analysis
• Web-based Debug Interface: Interactive browser-based complexity analyzer (Try it online)
• Xcode Integration: Seamless integration with Xcode via Build Tool Plugin for complexity feedback during build phase
• Xcode Diagnostics: Display complexity warnings and errors directly in Xcode editor with accurate line numbers
• Configurable Thresholds: Set custom complexity thresholds via Xcode Build Settings or environment variables
• Exit Code Integration: Returns exit code 1 when complexity thresholds are exceeded, perfect for CI/CD pipelines
• Multiple Output Formats: Text, JSON, XML, and Xcode diagnostics output for different use cases
• Flexible Analysis: Single files, directories, or recursive directory analysis
• Swift Syntax Based: Uses swift-syntax for accurate Swift code parsing
• Cross-Platform Support: CLI works on macOS and Linux, library works on iOS 13+.
• Extensible Architecture: Designed to support additional quality metrics in the future

Visit swift-complexity.fummicc1.dev to analyze Swift code instantly in your browser.

git clone https://github.com/fummicc1/swift-complexity
cd swift-complexity
swift build -c release

# Analyze a single file
swift run SwiftComplexityCLI path/to/file.swift

# Analyze a directory with threshold enforcement
swift run SwiftComplexityCLI Sources --threshold 10

# JSON output for tooling integration
swift run SwiftComplexityCLI Sources --format json --recursive

# Xcode diagnostics format (for IDE integration)
swift run SwiftComplexityCLI Sources --format xcode --threshold 15

The tool returns exit code 1 when any function exceeds the specified complexity threshold, making it ideal for:

• CI/CD Pipelines: Fail builds when complexity thresholds are exceeded
• Git Hooks: Prevent commits with overly complex code
• Code Quality Gates: Enforce complexity standards across teams

# Example: Fail if any function has complexity > 15
swift run SwiftComplexityCLI Sources --threshold 15 --recursive
# Exit code 0: All functions below threshold
# Exit code 1: One or more functions exceed threshold

• Cyclomatic Complexity: Measures the number of linearly independent paths through code
• Cognitive Complexity: Measures how difficult code is for humans to understand

Future metrics planned: LCOM, cohesion/coupling indicators

• User Guide: Installation, usage, and examples
• Complexity Metrics: Detailed metric explanations and examples
• Output Formats: JSON, XML, and text format specifications
• Development Guide: Setup for contributors
• Debug Website: Web-based interactive analyzer documentation

Unified package with multiple components:

• SwiftComplexityCore: Core analysis library (supports macOS 14+, iOS 13+)
• SwiftComplexityCLI: Command-line interface
• SwiftComplexityPlugin: Xcode Build Tool Plugin

• Frontend: Next.js application deployed on Cloudflare Workers
• Backend: Vapor 4 API containerized on Cloudflare Containers.
• Live Demo: swift-complexity.fummicc1.dev

# Analyze with verbose output
swift run SwiftComplexityCLI Sources --verbose --recursive

# Exclude test files with pattern matching  
swift run SwiftComplexityCLI Sources --recursive --exclude "*Test*.swift"

# Show only cognitive complexity above threshold
swift run SwiftComplexityCLI Sources --cognitive-only --threshold 5

Integrates with both Swift Package Manager and Xcode projects for automatic complexity analysis during builds.

// swift-tools-version: 6.1
import PackageDescription

let package = Package(
    name: "YourProject",
    dependencies: [
        .package(url: "https://github.com/fummicc1/swift-complexity.git", from: "1.0.0")
    ],
    targets: [
        .target(
            name: "YourTarget",
            plugins: [
                .plugin(name: "SwiftComplexityPlugin", package: "swift-complexity")
            ]
        )
    ]
)

1. Add swift-complexity package to your Xcode project
2. In Build Phases, add "SwiftComplexityPlugin" to Run Build Tool Plug-ins
3. Configure threshold in Build Settings (optional)

Xcode Build Settings:

• Key: SWIFT_COMPLEXITY_THRESHOLD
• Value: 15 (or any number, defaults to 10)

Environment Variable (SPM):

• SWIFT_COMPLEXITY_THRESHOLD=15

• Real-time feedback: Complexity warnings appear directly in Xcode editor
• Accurate positioning: Errors show at exact function locations
• Build integration: Builds fail when thresholds are exceeded
• Configurable per target: Different thresholds for different modules

File: Sources/ComplexityAnalyzer.swift
+------------------+----------+----------+
| Function/Method  | Cyclo.   | Cogn.    |
+------------------+----------+----------+
| analyzeFunction  |    3     |    2     |
| calculateTotal   |    5     |    7     |
+------------------+----------+----------+

Total: 2 functions, Average Cyclomatic: 4.0, Average Cognitive: 4.5

/path/to/Sources/MyFile.swift:45:1: error: Function 'complexFunction' has high complexity (Cyclomatic: 15, Cognitive: 23, Threshold: 10)
/path/to/Sources/MyFile.swift:89:1: warning: Function 'anotherFunction' has high complexity (Cyclomatic: 12, Cognitive: 18, Threshold: 10)

• Swift 6.1+
• macOS 14+ or Linux

• Swift 6.1+
• macOS 14+, iOS 13+, or Linux

MIT License