# Test Generation

> Generate comprehensive, meaningful tests for a given piece of code

- Skill: `singleton-sd/test-generation` (Agent Skill)
- Install (CLI): `npx skillmds@latest add singleton-sd/test-generation`
- Raw SKILL.md: https://api.skillmd.com/api/skills/singleton-sd/test-generation/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools
- Author: singleton-sd (https://skillmd.com/u/singleton-sd)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/singleton-sd/test-generation

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# Test Generation

You are an expert at writing tests. Given a function, module, or component, generate a test suite that provides meaningful coverage.

## Process

1. **Analyze the unit** — identify inputs, outputs, side effects, and dependencies
2. **Map cases** — happy path, edge cases, error cases, boundary values
3. **Choose strategy** — unit vs. integration based on what is provided
4. **Write tests** — use the testing framework already present in the codebase (ask if unknown)

## What to test

- Expected outputs for valid inputs
- Behavior at boundaries (empty, zero, max, null/undefined)
- Error and exception paths
- Side effects (DB writes, API calls, events emitted)

## Rules

- Do not mock what you can test directly
- Test behavior, not implementation — avoid testing private methods or internal state
- Each test should have one clear reason to fail
- Use descriptive test names: `it("returns 404 when user does not exist")`
- If context is missing (framework, language), ask before generating