test-writer
测试用例编写技能。当用户需要编写单元测试、集成测试、E2E 测试，或需要提高测试覆盖率、设计测试策略时使用此技能。
When & Why to Use This Skill
The Test Writer skill is a comprehensive assistant for software quality assurance, designed to automate the creation of high-quality, maintainable test cases. It helps developers implement the full testing pyramid—from unit and integration tests to end-to-end (E2E) scenarios—ensuring robust code reliability, high test coverage, and adherence to industry best practices like the AAA pattern and effective mocking strategies.
Use Cases
- Automated Unit Testing: Generate structured unit tests for complex business logic using the Arrange-Act-Assert (AAA) pattern to ensure individual components function correctly.
- Edge Case & Boundary Analysis: Design comprehensive test suites that specifically target boundary values and equivalence classes to catch bugs in corner cases.
- Mocking & Dependency Management: Create isolated test environments by identifying and mocking external dependencies such as APIs, databases, and third-party services.
- Test Coverage Improvement: Analyze existing codebases to identify untested paths and generate missing test cases for both happy paths and error handling.
- Test Strategy Design: Develop high-level testing strategies and naming conventions to maintain a clean, scalable, and readable test suite across large projects.
| name | test-writer |
|---|---|
| description | 测试用例编写技能。当用户需要编写单元测试、集成测试、E2E 测试，或需要提高测试覆盖率、设计测试策略时使用此技能。 |
Test Writer
编写高质量、可维护的测试用例，确保代码可靠性。
测试金字塔
/E2E\ 少量端到端测试
/------\
/集成测试\ 适量集成测试
/----------\
/ 单元测试 \ 大量单元测试
/--------------\
测试命名规范
test_[被测方法]_[场景]_[预期结果]
# 示例
test_login_withValidCredentials_returnsToken
test_divide_byZero_throwsException
test_createUser_duplicateEmail_returns409
单元测试结构 (AAA 模式)
def test_calculate_discount():
# Arrange - 准备测试数据
price = 100
discount_rate = 0.2
# Act - 执行被测方法
result = calculate_discount(price, discount_rate)
# Assert - 验证结果
assert result == 80
测试用例设计
边界值分析
- 最小值、最大值
- 边界值±1
- 空值、零值
等价类划分
- 有效等价类
- 无效等价类
必测场景
- ✅ 正常流程 (Happy Path)
- ❌ 异常流程 (Error Path)
- 🔲 边界条件 (Edge Cases)
- 🔒 权限验证 (Security)
Mock 使用原则
# 何时 Mock
- 外部服务（API、数据库）
- 不确定性因素（时间、随机数）
- 耗时操作
# 何时不 Mock
- 被测试的核心逻辑
- 简单的工具函数
测试质量检查
- 测试独立性：每个测试可单独运行
- 测试可重复：多次运行结果一致
- 测试快速：单元测试 < 100ms
- 断言明确：每个测试有清晰断言
- 覆盖充分：核心逻辑 > 80% 覆盖率