zero-nine-tdd-cycle

Imported from xingzhuangtang/Zero_Nine (adapters/opencode/.opencode/skills/zero-nine-tdd-cycle/SKILL.md). Install upstream with npx skills add xingzhuangtang/Zero_Nine --skill zero-nine-tdd-cycle. Copyright stays with the author.

TDD Cycle Skill

When to Use

• Task mode is tdd_cycle or implementation
• Implementation requires test coverage
• Working on features with clear acceptance criteria

Procedure

1. Read task contract - Load acceptance criteria and deliverables
2. Write failing test first:
   • Based on acceptance criteria
   • Run test to confirm it fails
3. Implement minimum code - Write just enough to pass the test
4. Run verification:
   • Execute tests
   • Check all acceptance criteria met
5. Refactor - Clean up while keeping tests green
6. Record evidence - Save test output, code diff, metrics

Evidence Artifacts

• test-output.txt - Test execution results
• code.diff - Changes made
• coverage.txt - Code coverage report (if applicable)

Pitfalls

• Don't write tests after implementation
• Don't implement more than needed for current test
• Don't skip refactoring step
• Don't proceed with failing tests

Verification

• All tests pass (cargo test --all-targets or equivalent)
• Code coverage >= 80% for new code
• Evidence artifacts saved to task directory