code-smell-detector

Code Smell Detector

Overview

Identify code quality and design smells in Python codebases, then provide specific refactoring recommendations to improve maintainability and design.

Workflow

1. Understand the Analysis Scope

Define what to analyze:

Questions to ask:

• What directory or files should be analyzed?
• Focus on quality smells, design smells, or both?
• Are there specific concerns (e.g., "this class is too complex")?
• Should test files be included?

Determine scope:

# Check project structure
ls -la

# Count Python files
find . -name "*.py" | wc -l

# Identify large files (potential smells)
find . -name "*.py" -exec wc -l {} + | sort -rn | head -10

2. Detect Code Smells

Use multiple detection strategies.

Strategy 1: Automated Detection

Use the bundled script for AST-based analysis:

# Scan entire project
python scripts/detect_smells.py /path/to/project

# Exclude specific directories
python scripts/detect_smells.py /path/to/project venv,tests,docs

What it detects:

• Long methods (>50 lines)
• Too many parameters (>5)
• Large classes (>15 methods)
• God classes (>20 methods)
• Magic numbers

Strategy 2: Manual Code Review

Read the code to identify design smells. See smell-patterns.md for comprehensive catalog.

Look for:

Code Quality Smells:

• Duplicate code blocks
• Magic numbers (unexplained numeric literals)
• Hardcoded values (paths, URLs, config)
• Commented-out code
• Inconsistent naming

Design Smells:

• God classes (too many responsibilities)
• Feature envy (method uses more from another class)
• Inappropriate intimacy (classes too coupled)
• Data clumps (same parameters repeated)
• Primitive obsession (using primitives instead of objects)
• Long parameter lists (>5 parameters)

Search patterns:

# Find long files (potential large classes)
find . -name "*.py" -exec wc -l {} + | awk '$1 > 300'

# Find magic numbers (basic pattern)
grep -r "[^0-9]\d\{3,\}" --include="*.py" .

# Find hardcoded paths
grep -r '"/.*/"' --include="*.py" .

# Find commented code
grep -r "^[ ]*#.*def \|^[ ]*#.*class " --include="*.py" .