test-writer

ADD Test Writer Skill v{{VERSION}}

Generate comprehensive failing tests from a feature specification. This is the RED phase of TDD — write tests before implementation.

Overview

Test Writer converts acceptance criteria and user test cases from a spec into failing, runnable tests. The output is test files that:

• Compile and execute but fail (RED state)
• Have clear, descriptive names mapped to ACs
• Cover all acceptance criteria and user test cases
• Follow the project's test conventions
• Are production-quality (good error messages, clear assertions)

Pre-Flight Checks

1. Verify spec file exists and is readable

   • Read the spec at the provided path
   • Extract frontmatter: feature name, version, status

2. Parse acceptance criteria

   • Read the Acceptance Criteria section
   • Extract each AC with its ID (AC-001, AC-002, etc.)
   • Extract the criteria description and conditions

3. Parse user test cases

   • Read the User Test Cases section (if present)
   • Extract each UT with ID (UT-001, UT-002, etc.)
   • Note the setup, actions, and expected outcomes

4. Load test framework configuration

   • Read .add/config.json
   • Identify test.framework (jest, pytest, vitest, mocha, pytest, etc.)
   • Load test.convention (naming pattern, directory structure, imports)
   • Check test.type to determine default test type

5. Identify test file location

   • Determine target directory from config (typically tests/ or __tests__/)
   • Determine file naming from convention
   • Check if test file already exists; if so, append new tests

6. Check for session handoff — per the Session-Handoff Preflight in ${CLAUDE_PLUGIN_ROOT}/references/skill-epilogue.md

Execution Steps

Step 1: Analyze Acceptance Criteria

For each acceptance criterion:

1. Extract the requirement statement
2. Break down into testable assertions
3. Identify input conditions, actions, and expected outputs
4. Note any data setup required
5. Consider both happy path and edge cases