CodeSearch

Fast, intelligent code search and analysis for 48+ languages.

Find what you need in seconds: functions, classes, duplicates, dead code, complexity issues.

What Can You Search & Detect?

🔍 Search Capabilities

Supports: Regex, fuzzy matching, case-insensitive, multi-language (48+ languages)

🔎 Code Quality Detection

💡 Real-World Use Cases

Before Refactoring:

# Find all usages of old function
codesearch "oldAuthMethod" .
# Result: Found in 12 files, 23 occurrences

Code Review:

# Check for technical debt
codesearch deadcode ./src
# Result: 5 unused functions, 12 TODO comments

Understanding Codebase:

# Find all authentication-related code
codesearch "auth" -e rs,py --rank
# Result: Ranked by relevance, with line numbers

Quality Check:

# Find duplicated code
codesearch duplicates --min-lines 5
# Result: 8 duplicate blocks (90%+ similar)

🚀 Quick Start

# Simple search: codesearch <query> [path]
codesearch "function"           # Search current directory
codesearch "TODO" ./src         # Search specific path
codesearch "class" ./src -e py  # Filter by extension

# Fuzzy search (handles typos)
codesearch "usrmngr" . --fuzzy

# Interactive mode
codesearch interactive

# Analysis commands
codesearch analyze              # Codebase metrics
codesearch complexity           # Complexity scores
codesearch metrics              # Comprehensive metrics (all-in-one)
codesearch design-metrics       # Coupling & cohesion
codesearch duplicates           # Find similar code
codesearch deadcode             # Find unused code

# Advanced features
codesearch index                # Build incremental index
codesearch watch                # Watch for file changes

# Graph analysis (6 types)
codesearch ast file.rs          # Abstract Syntax Tree
codesearch cfg file.rs          # Control Flow Graph
codesearch dfg file.rs          # Data Flow Graph
codesearch callgraph .          # Call Graph
codesearch depgraph .           # Dependency Graph
codesearch pdg file.rs          # Program Dependency Graph
codesearch graph-all file.rs    # All graphs

# Other advanced features
codesearch git-history "TODO"   # Search git history
codesearch remote --github "pattern" # Search GitHub

Why CodeSearch?

Fast & Precise

• Parallel processing using Rust and rayon
• Exact line numbers with precise matching
• Smart caching for repeated searches
• Typical search: 3-50ms for codebases < 1000 files

Language-Aware

• 48+ languages supported
• Understands functions, classes, imports
• Syntax-specific patterns

Quality Focused

• Detect dead code before it ships
• Find duplicates to improve DRY
• Measure complexity to guide refactoring
• Analyze design quality (coupling, cohesion, instability)

Developer Friendly

• Interactive REPL mode
• Export to CSV/Markdown
• MCP server for AI agents

Advanced Capabilities

• Incremental indexing for large codebases
• Real-time file watching
• Git history search
• Remote repository search (GitHub/GitLab)

Graph Analysis (6 Types)

• Abstract Syntax Tree (AST) - code structure
• Control Flow Graph (CFG) - execution paths
• Data Flow Graph (DFG) - variable dependencies
• Call Graph - function relationships
• Dependency Graph - module dependencies
• Program Dependency Graph (PDG) - combined analysis

High Code Quality

• ✅ 100% test pass rate (173 unit + 36 integration tests)
• ✅ Zero clippy warnings (as of Jan 2026)
• ✅ Modular architecture (19 focused modules)
• ✅ DRY, KISS, and SoC principles throughout
• ✅ Thread-safe parallel processing
• ✅ Comprehensive error handling

Installation

git clone https://github.com/yingkitw/codesearch.git
cd codesearch
cargo build --release

# Optional: MCP server for AI agents
cargo build --release --features mcp

Common Options

# Filter by file type
codesearch "pattern" -e rs,py,js

# Exclude directories
codesearch "pattern" -x target,node_modules

# Case-insensitive
codesearch "pattern" -i

# Fuzzy matching (handles typos)
codesearch "patern" --fuzzy

# Rank by relevance
codesearch "pattern" --rank

# Export results
codesearch "pattern" --export csv

📖 Usage Examples

Search Patterns

# codesearch <query> [path] [options]
codesearch "TODO"                       # Search current directory
codesearch "class" ./src                # Search specific folder
codesearch "error" . -e py,js,ts        # Filter by extensions

# Regex patterns
codesearch "fn\\s+\\w+" ./src -e rs     # Rust functions
codesearch "import.*from" . -e ts       # TypeScript imports

# Fuzzy search (handles typos)
codesearch "authetication" . --fuzzy    # Finds "authentication"

Code Analysis

# Codebase overview
codesearch analyze
# Output: Files, lines, languages, function count, class count

# Complexity analysis
codesearch complexity --threshold 15 --sort
# Output: Files ranked by cyclomatic/cognitive complexity

# Dead code detection (enhanced with 6+ detection types)
codesearch deadcode -e rs,py,js
# Output: Unused variables, unreachable code, empty functions, 
#         TODO/FIXME markers, commented code, unused imports

# Duplicate detection
codesearch duplicates --similarity 0.8
# Output: Similar code blocks that violate DRY

Interactive Mode

codesearch interactive

Commands:

• Type any pattern to search
• /f - Toggle fuzzy mode
• /i - Toggle case insensitivity
• analyze - Codebase metrics
• complexity - Complexity analysis
• deadcode - Dead code detection
• duplicates - Find duplicates
• help - All commands

MCP Server (AI Integration)

# Start MCP server
cargo run --features mcp -- mcp-server

# Agents can call:
# - search_code(query, path, extensions, fuzzy, regex)
# - list_files(path, extensions, exclude)
# - analyze_codebase(path, extensions)

📊 Output Examples

Search Results

🔍 Search Results for "fn main"
──────────────────────────────

📁 ./src/main.rs (1 match)
  358: fn main() -> Result<(), Box<dyn std::error::Error>> {

📊 Statistics:
  Files searched: 12
  Matches found: 1
  Time: 0.003s

Dead Code Detection

🔍 Dead Code Detection
──────────────────────────────

⚠️  Found 12 potential dead code items:

📄 src/example.rs
   [var] L  10: variable 'unused_var' - Variable declared but never used
   [!]   L  25: unreachable - Code after return statement is unreachable
   [∅]   L  42: empty_helper - Empty function with no implementation
   [?]   L  58: // TODO: implement this - TODO marker - incomplete implementation
   [imp] L  72: import 'HashMap' - Imported but never used

📊 Summary:
   • variable: 3
   • unreachable: 2
   • empty: 2
   • todo: 3
   • import: 2

Complexity Analysis

📊 Code Complexity Analysis
──────────────────────────────

📁 Files by Complexity (highest first):

  src/search.rs
    Cyclomatic: 45  Cognitive: 38  Lines: 645

  src/analysis.rs
    Cyclomatic: 28  Cognitive: 22  Lines: 378

Code Quality & Architecture

Maintainability

• Modular Design: 19 focused modules following single responsibility principle
• Clean Code: Average module size ~200 LOC, functions < 100 LOC
• Design Patterns: Strategy, Observer, Facade patterns for extensibility
• Best Practices: DRY, KISS, SoC principles consistently applied

Test Coverage

• 173 Unit Tests: Core functionality thoroughly tested
• 36 Integration Tests: End-to-end CLI command verification
• 23 MCP Tests: AI agent integration validated
• Edge Cases: Empty files, unicode, large files, special characters

Performance

• Parallel Processing: Auto-scales to available CPU cores with rayon
• Smart Caching: 70-90% cache hit rate for repeated searches
• Memory Efficient: Streaming file reading, < 100MB for 10K files
• Optimized: Regex compilation moved outside loops, fast hashing with ahash

Future Improvements

See TODO.md for planned enhancements:

• Trait abstractions for better testability
• Property-based testing with proptest
• Performance profiling and optimization
• Enhanced caching with LRU eviction
• Workspace crate structure for modularity

Supported Languages

48+ languages including: Rust, Python, JavaScript, TypeScript, Go, Java, C/C++, Ruby, PHP, Swift, Kotlin, and more.

See ARCHITECTURE.md for technical details and design principles.

License

Apache-2.0 License

Built with Rust • Fast • Precise • 48+ Languages