AI_template/.claude/skills/write-tests/SKILL.md

name, description, disable-model-invocation, argument-hint, context, agent

name	description	disable-model-invocation	argument-hint	context	agent
write-tests	Write tests for a specific file — unit and integration tests with Vitest, Testing Library, accessible queries, and AAA pattern.	true	[file-path]	fork	test-engineer

Write Tests

Write comprehensive tests for $ARGUMENTS.

Steps

1. Read the target file and understand:

   • What it does (component, service, utility, API handler)
   • Its dependencies and side effects
   • Edge cases and error paths

2. Read project context:

   • Check RECOMMENDATIONS.md for testing stack decisions
   • Look at existing test files for patterns and conventions
   • Check test config (vitest.config, playwright.config)

3. Write tests following these rules:

   Structure:

   • AAA pattern (Arrange → Act → Assert)
   • Behavior-focused names: it('displays error when API fails')
   • Group by concern: describe('when user is logged in', ...)
   • Co-locate with source file: Component.test.tsx next to Component.tsx

   Queries (for React components):

   • getByRole → getByLabelText → getByText → getByTestId (last resort)
   • Use userEvent over fireEvent

   Mocking:

   • MSW for HTTP APIs
   • vi.mock() only for third-party services
   • Real implementations for internal logic
   • Deterministic test data via factories

   Coverage:

   • Happy path
   • Error states
   • Empty/loading states
   • Edge cases (null, undefined, empty arrays, boundary values)
   • Accessibility: keyboard interaction, ARIA states

4. No arbitrary waits — use waitFor, findBy, or proper async handling.

5. Output: working test file, ready to run with vitest.