# Test Implement

> Implements React/TypeScript unit, integration, and browser E2E tests with the repository's configured runner, mocks, setup, and browser harness. Use when creating or completing frontend tests and generated test skeletons.

- Skill: `shinpr/test-implement` (Agent Skill, multi-file: 3 files)
- Install (CLI): `npx skillmds@latest add shinpr/test-implement`
- Raw SKILL.md: https://api.skillmd.com/api/skills/shinpr/test-implement/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Web & Frontend
- Author: shinpr (https://skillmd.com/u/shinpr)
- Updated: 2026-09-09
- Page: https://skillmd.com/skills/shinpr/test-implement

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# Test Implementation Patterns

## Reference Selection

| Test Type | Reference | When to Use |
|-----------|-----------|-------------|
| **Unit / Integration** | [references/frontend.md](references/frontend.md) | Implementing React component tests with the repository's configured runner and network mocking layer |
| **E2E** | [references/e2e.md](references/e2e.md) | Implementing browser-level E2E tests in the existing harness, or Playwright when the approved work introduces a harness |

## Common Principles

### AAA Structure
All tests follow **Arrange-Act-Assert**:
- **Arrange**: Set up preconditions and inputs
- **Act**: Execute the behavior under test
- **Assert**: Verify the expected outcome

### Test Independence
- Each test runs independently without depending on other tests
- No shared mutable state between tests
- Deterministic execution — mock random and time dependencies

### Naming
- Test names describe expected behavior from user perspective
- One test verifies one behavior