AgentSkillsCN

scenario-testing

在编写测试、验证功能或需要确认代码正常工作时应使用此技能。触发词包括“编写测试”、“增加测试覆盖率”、“验证功能”、“集成测试”、“端到端”、“e2e测试”、“mock”、“单元测试”。强制使用场景驱动的测试，依赖真实数据存放在.scratch/目录中。

SKILL.md
--- frontmatter
name: scenario-testing
description: This skill should be used when writing tests, validating features, or needing to verify code works. Triggers on "write tests", "add test coverage", "validate feature", "integration test", "end-to-end", "e2e test", "mock", "unit test". Enforces scenario-driven testing with real dependencies in .scratch/ directory.

Scenario-Driven Testing for AI Code Generation

Core Principle

The Iron Law: "NO FEATURE IS VALIDATED UNTIL A SCENARIO PASSES WITH REAL DEPENDENCIES"

Mocks create false confidence. Only scenarios exercising real systems validate that code works.

The Truth Hierarchy

  1. •Scenario tests (real system, real data) = truth
  2. •Unit tests (isolated) = human comfort only
  3. •Mocks = lies hiding bugs

As stated in the principle: "A test that uses mocks is not testing your system. It's testing your assumptions about how dependencies behave."

When to Use This Skill

  • •Validating new functionality
  • •Before declaring work complete
  • •When tempted to use mocks
  • •After fixing bugs requiring verification
  • •Any time you need to prove code works

Required Practices

1. Write Scenarios in .scratch/

  • •Use any language appropriate to the task
  • •Exercise the real system end-to-end
  • •Zero mocks allowed
  • •Must be in .gitignore (never commit)

2. Promote Patterns to scenarios.jsonl

  • •Extract recurring scenarios as documented specifications
  • •One JSON line per scenario
  • •Include: name, description, given/when/then, validates
  • •This file IS committed

3. Use Real Dependencies

External APIs must hit actual services (sandbox/test mode acceptable). Mocking any dependency invalidates the scenario.

4. Independence Requirement

Each scenario must run standalone without depending on prior executions. This enables:

  • •Parallel execution
  • •Prevents hidden ordering dependencies
  • •Reliable CI/CD integration

What Makes a Scenario Invalid

A scenario is invalid if it:

  • •Contains any mocks whatsoever
  • •Uses fake data instead of real storage
  • •Depends on another scenario running first
  • •Never actually executed to verify it passes

Common Violations to Avoid

Reject these rationalizations:

  • •"Just a quick unit test..." - Unit tests don't validate features
  • •"Too simple for end-to-end..." - Integration breaks simple things
  • •"I'll mock for speed..." - Speed doesn't matter if tests lie
  • •"I don't have API credentials..." - Ask your human partner for real ones

Definition of Done

A feature is complete only when:

  1. •✅ A scenario in .scratch/ passes with zero mocks
  2. •✅ Real dependencies are exercised
  3. •✅ .scratch/ remains in .gitignore
  4. •✅ Robust patterns extracted to scenarios.jsonl

Example Workflow

  1. •Write scenario - Create .scratch/test-user-registration.py
  2. •Use real dependencies - Hit real database, real auth service (test mode)
  3. •Run and verify - Execute scenario, confirm it passes
  4. •Extract pattern - Document in scenarios.jsonl
  5. •Keep .scratch ignored - Never commit scratch scenarios

Why This Matters

  • •Unit tests verify isolated logic
  • •Integration tests verify components work together
  • •Scenario tests verify the system actually works

Only scenario tests prove your feature delivers value to users.