Contributing to Filter 
Thank you for your interest in contributing to @mcabreradev/filter! This guide will help you get started.
Table of Contents 
- Code of Conduct
- Getting Started
- Development Setup
- Project Structure
- Development Workflow
- Testing
- Documentation
- Pull Request Process
- Coding Standards
- Framework Integrations
- Performance Considerations
Code of Conduct 
By participating in this project, you agree to maintain a respectful and inclusive environment for all contributors.
Our Standards 
- Use welcoming and inclusive language
- Be respectful of differing viewpoints and experiences
- Gracefully accept constructive criticism
- Focus on what is best for the community
- Show empathy towards other community members
Getting Started 
Fork and Clone 
- Fork the repository on GitHub
- Clone your fork locally:
git clone https://github.com/YOUR_USERNAME/filter.git
cd filter- Add upstream remote:
git remote add upstream https://github.com/mcabreradev/filter.gitStay Synced 
Keep your fork up to date:
git fetch upstream
git checkout main
git merge upstream/mainDevelopment Setup 
Prerequisites 
- Node.js 18+ or 20+
- pnpm 8+ (recommended)
Installation 
pnpm installAvailable Scripts 
pnpm test
pnpm test:watch
pnpm test:coverage
pnpm test:types
pnpm build
pnpm type-check
pnpm docs:dev
pnpm docs:buildProject Structure 
filter/
├── src/
│   ├── core/              # Core filter functionality
│   │   ├── filter.ts
│   │   ├── filter-lazy.ts
│   │   └── index.ts
│   ├── operators/         # Operator implementations
│   │   ├── comparison.operators.ts
│   │   ├── logical.operators.ts
│   │   ├── string.operators.ts
│   │   ├── array.operators.ts
│   │   └── operator-processor.ts
│   ├── comparison/        # Comparison utilities
│   │   ├── deep-compare.ts
│   │   ├── object-compare.ts
│   │   └── property-compare.ts
│   ├── config/            # Configuration
│   │   ├── config-builder.ts
│   │   └── default-config.ts
│   ├── integrations/      # Framework integrations
│   │   ├── react/
│   │   ├── vue/
│   │   ├── svelte/
│   │   └── shared/
│   ├── predicate/         # Predicate functions
│   ├── types/             # TypeScript type definitions
│   ├── utils/             # Utility functions
│   └── validation/        # Validation schemas
├── __test__/              # Test files
├── docs/                  # Documentation
├── examples/              # Usage examples
└── build/                 # Build outputDevelopment Workflow 
1. Create a Branch 
git checkout -b feature/your-feature-nameBranch naming conventions:
- feature/- New features
- fix/- Bug fixes
- docs/- Documentation changes
- refactor/- Code refactoring
- test/- Test additions/changes
- chore/- Maintenance tasks
2. Make Changes 
- Write clean, readable code
- Follow TypeScript best practices
- Add/update tests
- Update documentation
3. Test Your Changes 
pnpm test
pnpm test:coverage
pnpm type-check4. Commit Changes 
Follow Conventional Commits:
git commit -m "feat: add new operator for date filtering"
git commit -m "fix: resolve memory leak in memoization"
git commit -m "docs: update React integration guide"Commit types:
- feat:- New feature
- fix:- Bug fix
- docs:- Documentation changes
- style:- Code style changes (formatting)
- refactor:- Code refactoring
- test:- Test changes
- chore:- Maintenance tasks
- perf:- Performance improvements
5. Push and Create PR 
git push origin feature/your-feature-nameOpen a Pull Request on GitHub.
Testing 
Unit Tests 
All new features and bug fixes must include tests.
pnpm test
pnpm test:watch
pnpm test filter.test.tsType Tests 
Type-level tests ensure TypeScript types work correctly:
pnpm test:typesCoverage 
Maintain 100% code coverage:
pnpm test:coverageWriting Tests 
Follow these guidelines:
1. Descriptive Names
it('should filter users by age greater than 18', () => {
  // test
});2. Arrange-Act-Assert Pattern
it('should filter array by simple condition', () => {
  const data = [{ age: 25 }, { age: 30 }];
  const expression = { age: { $gt: 26 } };
  const result = filter(data, expression);
  expect(result).toEqual([{ age: 30 }]);
});3. Test Edge Cases
it('should handle empty arrays', () => {
  expect(filter([], expression)).toEqual([]);
});
it('should handle null values', () => {
  const data = [{ age: null }, { age: 25 }];
  expect(filter(data, { age: { $gt: 20 } })).toEqual([{ age: 25 }]);
});4. Test Error Conditions
it('should throw error for invalid operator', () => {
  expect(() => filter(data, { age: { $invalid: 20 } }))
    .toThrow('Invalid operator');
});Documentation 
Code Documentation 
Add JSDoc comments for public APIs:
/**
 * Filters an array based on the provided expression.
 *
 * @template T - The type of items in the array
 * @param data - The array to filter
 * @param expression - The filter expression
 * @param options - Optional configuration
 * @returns Filtered array
 *
 * @example
 * ```typescript
 * const users = [{ age: 25 }, { age: 30 }];
 * const filtered = filter(users, { age: { $gte: 26 } });
 * ```
 */
export function filter<T>(
  data: T[],
  expression: Expression<T>,
  options?: FilterOptions
): T[] {
  // implementation
}Documentation Site 
Documentation is built with VitePress:
pnpm docs:dev
pnpm docs:buildWhen adding features:
- Update relevant documentation pages
- Add examples to docs/examples/
- Update API reference
- Add to changelog
Pull Request Process 
Before Submitting 
Checklist:
- [ ] Tests pass locally
- [ ] Code follows style guidelines
- [ ] Documentation is updated
- [ ] Type checks pass
- [ ] No linter errors
- [ ] Commit messages follow conventions
- [ ] Branch is up to date with main
PR Description Template 
## Description
Brief description of changes and motivation.
## Type of Change
- [ ] ✨ New feature
- [ ] 🛠️ Bug fix
- [ ] ❌ Breaking change
- [ ] 🧹 Code refactor
- [ ] 📝 Documentation
- [ ] 🗑️ Chore
## Testing
- [ ] Unit tests added/updated
- [ ] Type tests added/updated
- [ ] All tests pass
- [ ] Coverage maintained at 100%
## Documentation
- [ ] Documentation updated
- [ ] Examples added/updated
- [ ] API reference updated
- [ ] Changelog updated
## Checklist
- [ ] Code builds successfully
- [ ] No TypeScript errors
- [ ] No linter issues
- [ ] Follows coding standardsReview Process 
- Maintainers review your PR
- Address feedback and requested changes
- Once approved, PR will be merged
- Your contribution will be included in the next release
Coding Standards 
TypeScript 
- Use strict TypeScript mode
- Prefer interfaceovertypefor objects
- Avoid any- use proper types
- Use type guards for runtime checks
- Leverage type inference
interface User {
  id: number;
  name: string;
  age: number;
}
function isUser(value: unknown): value is User {
  return (
    typeof value === 'object' &&
    value !== null &&
    'id' in value &&
    'name' in value &&
    'age' in value
  );
}Code Style 
- Use functional programming patterns
- Follow DRY principle
- Keep functions small and focused
- Use meaningful names
- Avoid side effects
const filterByAge = (minAge: number) => (user: User) => user.age >= minAge;
const adults = users.filter(filterByAge(18));Naming Conventions 
- camelCase- variables, functions, methods
- PascalCase- types, interfaces, classes
- kebab-case- file names
- UPPERCASE- constants, environment variables
const userName = 'John';
interface UserProfile {
  id: number;
}
const MAX_RETRIES = 3;File Organization 
feature/
├── feature.ts              # Main implementation
├── feature.types.ts        # Type definitions
├── feature.utils.ts        # Utility functions
├── feature.constants.ts    # Constants
├── feature.test.ts         # Unit tests
└── index.ts                # Public exportsFramework Integrations 
When adding framework integrations:
1. Follow Framework Best Practices 
React: Use hooks, avoid class components Vue: Use Composition API Svelte: Use stores
2. Maintain Type Safety 
export function useFilter<T>(
  data: T[],
  expression: Expression<T>,
  options?: FilterOptions
): UseFilterResult<T> {
  // implementation
}3. Add Comprehensive Examples 
Include examples for common use cases.
4. Update Framework Documentation 
Add/update documentation in docs/frameworks/.
5. Add Integration Tests 
Test framework-specific behavior.
Performance Considerations 
Benchmarking 
Benchmark performance-critical changes:
console.time('filter');
const result = filter(largeDataset, expression);
console.timeEnd('filter');Optimization Guidelines 
- Use memoization for expensive operations
- Implement lazy evaluation where appropriate
- Avoid unnecessary re-renders in React
- Minimize reactivity overhead in Vue
- Optimize store updates in Svelte
Memory Management 
- Clear caches when appropriate
- Avoid memory leaks in subscriptions
- Use weak references where possible
Questions and Support 
- Questions: Open a GitHub Discussion
- Bugs: Open a GitHub Issue
- Security: Email security@mcabreradev.com
Recognition 
Contributors are recognized in:
- README.md contributors section
- Release notes
- GitHub contributors page
Thank you for contributing! 🎉
License 
By contributing, you agree that your contributions will be licensed under the MIT License.