python.cursorrules

# Python Rules

## Style & Structure
- Use type hints for all function signatures and return types
- Prefer f-strings over .format() or % formatting
- Use pathlib instead of os.path for file operations
- Prefer list/dict/set comprehensions over map/filter when readable
- Use dataclasses or Pydantic models instead of plain dicts for structured data

## Error Handling
- Use specific exception types, never bare except
- Use contextlib.suppress() for expected exceptions
- Return early to avoid deep nesting

## Imports
- Group imports: stdlib, third-party, local (separated by blank lines)
- Use absolute imports over relative imports
- Never use wildcard imports (from x import *)

## Functions
- Keep functions under 30 lines — extract helpers
- Use *args and **kwargs sparingly and document when used
- Prefer returning values over modifying mutable arguments
- Use generators for large sequences (yield over building lists)

## Testing
- Use pytest over unittest
- Name tests descriptively: test_<function>_<scenario>_<expected>
- Use fixtures for shared setup, parametrize for multiple cases