mo-code: Skill for Claude Code

Test Generator Skill

Auto-suggest tests when you write new code.

When I Activate

• ✅ New function created
• ✅ New component added
• ✅ User mentions testing or tests
• ✅ Test file missing for implementation
• ✅ User asks "can you test this?"

What I Generate

Quick Test Scaffolding

• Basic happy path tests
• Null/undefined edge cases
• Simple error scenarios
• Framework-appropriate syntax (Jest/Vitest/Pytest)

What I Don't Do

• Comprehensive test suites → Use @test-engineer sub-agent
• Integration tests → Use @test-engineer sub-agent
• E2E test design → Use @test-engineer sub-agent
• Test strategy planning → Use @test-engineer sub-agent

Relationship with @test-engineer Sub-Agent

Me (Skill): Quick test scaffolding @test-engineer (Sub-Agent): Comprehensive testing strategy

Workflow

1. You write a function
2. I auto-generate basic test structure
3. You want full suite → Invoke @test-engineer sub-agent
4. Sub-agent creates comprehensive tests

Examples

JavaScript Function

// You write:
function calculateDiscount(price, percentage) {
  if (price <= 0) throw new Error('Invalid price');
  return price * (percentage / 100);
}

// I auto-generate:
describe('calculateDiscount', () => {
  it('calculates discount correctly', () => {
    expect(calculateDiscount(100, 10)).toBe(10);
  });

  it('throws error for invalid price', () => {
    expect(() => calculateDiscount(0, 10)).toThrow('Invalid price');
  });

  it('handles zero percentage', () => {
    expect(calculateDiscount(100, 0)).toBe(0);
  });

  // TODO: Add more edge cases
  // Consider: negative percentages, decimal values, very large numbers
});

React Component

// You write:
function UserCard({ user, onEdit }) {
  return (
    <div className="user-card">
      <h2>{user.name}</h2>
      <button onClick={() => onEdit(user.id)}>Edit</button>
    </div>
  );
}

// I auto-generate:
import { render, screen, fireEvent } from '@testing-library/react';

describe('UserCard', () => {
  const mockUser = { id: 1, name: 'John Doe' };
  const mockOnEdit = jest.fn();

  it('renders user name', () => {
    render(<UserCard user={mockUser} onEdit={mockOnEdit} />);
    expect(screen.getByText('John Doe')).toBeInTheDocument();
  });

  it('calls onEdit with user id when button clicked', () => {
    render(<UserCard user={mockUser} onEdit={mockOnEdit} />);
    fireEvent.click(screen.getByText('Edit'));
    expect(mockOnEdit).toHaveBeenCalledWith(1);
  });

  // TODO: Add tests for edge cases
  // - Missing user data
  // - Undefined onEdit
  // - Long names (UI testing)
});