test-writer

Test Writer

Write and maintain tests for the Raamattu Nyt monorepo.

Context Files (Read First)

For structure and conventions, read from Docs/context/:

• Docs/context/repo-structure.md - Where test files go
• Docs/context/conventions.md - Naming patterns

Quick Start

# Run all tests
npm test

# Run with coverage
npm run test:coverage

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

Test File Conventions

• Place tests adjacent to source: useHook.ts → useHook.test.ts
• Use .test.ts for pure logic, .test.tsx for React components/hooks
• Name: describe("ComponentName") or describe("hookName")

Standard Test Structure

import { describe, expect, it, vi, beforeEach } from "vitest";

// Mocks BEFORE imports (hoisted)
vi.mock("@/integrations/supabase/client", () => ({
  supabase: { rpc: vi.fn() }
}));

// Import module under test AFTER mocks
import { myFunction } from "./myModule";

describe("myFunction", () => {
  beforeEach(() => {
    vi.clearAllMocks();
  });

  it("does expected behavior", () => {
    expect(myFunction()).toBe(expected);
  });
});

Hook Testing Pattern

import { renderHook, waitFor } from "@testing-library/react";

// Wrapper for context providers
const wrapper = ({ children }) => (
  <AuthProvider>{children}</AuthProvider>
);

it("returns initial state", () => {
  const { result } = renderHook(() => useMyHook(), { wrapper });
  expect(result.current.loading).toBe(true);
});

it("updates on async action", async () => {
  const { result } = renderHook(() => useMyHook(), { wrapper });
  await waitFor(() => {
    expect(result.current.data).toBeDefined();
  });
});

Common Mocks

See references/mocks.md for reusable mock patterns:

• Supabase client (RPC, auth, schema queries)
• useAuth hook
• React Query
• localStorage

Workflow

1. Identify what to test

   • Use code-wizard skill to find the file/function
   • Check git log for recent changes: git log --oneline -20

2. Check existing tests

   • Find tests: Glob pattern: **/*.test.{ts,tsx}
   • Read related test files for patterns

3. Write tests covering

   • Happy path (normal operation)
   • Error cases (API failures, invalid input)
   • Edge cases (empty arrays, null, undefined)
   • Loading states for async operations

4. Run and verify

   npx vitest run path/to/file.test.ts
   

Test Quality Checklist

• Tests are independent (no shared state between tests)
• Mocks are cleared in beforeEach
• Async operations use waitFor not arbitrary delays
• Error scenarios are tested
• Edge cases covered (null, empty, boundary values)

Related Skills