/test — Testing Workflows

Write, run, and analyze tests for SaaS applications using Vitest and Playwright.

Modes

Specify which mode when invoking:

• /test write — Write tests for specified files/features
• /test run — Run existing tests
• /test coverage — Run tests with coverage analysis

Mode: Write Tests

1. Identify what to test — Read the source file(s) and understand the behavior
2. Check existing tests — Look for existing test patterns in the project
3. Write tests following these patterns:

Server Actions:

import { describe, it, expect, vi } from 'vitest';

// Mock Supabase
vi.mock('@/lib/supabase/server', () => ({
  createClient: vi.fn(() => mockSupabaseClient),
}));

describe('createProject', () => {
  it('creates a project for authenticated user', async () => {
    // Arrange: set up mocks
    // Act: call the server action
    // Assert: verify behavior
  });

  it('redirects to login if not authenticated', async () => { ... });
  it('returns error for invalid input', async () => { ... });
});

API Routes (webhook handlers):

describe('POST /api/webhooks/stripe', () => {
  it('verifies webhook signature', async () => { ... });
  it('handles checkout.session.completed', async () => { ... });
  it('returns 400 for invalid signature', async () => { ... });
});

React Components:

import { render, screen } from '@testing-library/react';
import userEvent from '@testing-library/user-event';

describe('PricingCard', () => {
  it('renders plan name and price', () => { ... });
  it('calls checkout on button click', async () => { ... });
  it('shows current plan badge for active subscription', () => { ... });
});

Stripe integration tests:

• Use Stripe test mode keys
• Mock stripe.webhooks.constructEvent for webhook tests
• Test subscription gating logic with different subscription states

Mode: Run Tests

# Run all unit/integration tests
npx vitest run

# Run specific test file
npx vitest run path/to/test.ts

# Run tests matching pattern
npx vitest run -t "pattern"

# Run E2E tests
npx playwright test

# Run specific E2E test
npx playwright test path/to/test.ts

Report results to the user with pass/fail summary and any error details.

Mode: Coverage

npx vitest run --coverage

Analyze coverage output and report:

• Overall coverage percentage
• Files with lowest coverage
• Untested critical paths (auth, billing, data access)
• Recommendations for where to add tests

Test File Naming

• Unit/integration: *.test.ts or *.test.tsx next to source file
• E2E: e2e/*.spec.ts

Rules

• Only run tests with npx vitest or npx playwright — no other bash commands
• Follow existing test patterns in the project
• Test behavior, not implementation details
• Keep tests independent — no shared mutable state
• Use descriptive test names: it('redirects to login when not authenticated')
• Launch the testing-specialist agent for complex test writing tasks