Can this skill generate tests for existing legacy code?

Yes, it includes specific commands to analyze existing files and generate comprehensive tests covering happy paths, edge cases, and error conditions.

Which testing frameworks are supported by this skill?

The skill provides specific patterns and templates for Jest, Vitest, and pytest, though the core TDD and coverage concepts can be adapted to almost any testing library.

Does it support end-to-end (E2E) testing?

Yes, it includes patterns for generating E2E tests using Playwright, including multi-step user flows and UI verification.

How does it help with code coverage?

It provides commands to run coverage reports and prompts that allow Claude to analyze those reports, identify untested branches, and generate the necessary tests to fill gaps.

Testing Patterns for Claude Code

Name: Testing Patterns for Claude Code
Author: hgeldenhuys

byhgeldenhuys

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Security & Testing

Implements systematic TDD workflows, automated test generation, and comprehensive coverage strategies across major testing frameworks.

The Testing Patterns skill provides a robust framework for managing the software testing lifecycle within Claude Code. It enables developers to implement disciplined Test-Driven Development (TDD) cycles, generate high-quality unit and integration tests for existing code, and perform deep coverage analysis to identify untested execution paths. By standardizing mocking patterns and providing edge-case checklists for frameworks like Jest, Vitest, and pytest, this skill ensures that AI-generated code remains reliable, maintainable, and production-ready.

Key Features

01Automated test generation from existing code and specifications

02Structured Red-Green-Refactor TDD workflow integration

03Pre-built mocking patterns for external services and APIs

041 GitHub stars

05Comprehensive coverage gap analysis for JS/TS and Python

06Edge case checklists for boundary and error condition testing

Use Cases

01Generating E2E Playwright tests for complex user workflows

02Developing new features using a strict test-first methodology

03Rapidly increasing test coverage for legacy or untested codebases

What are Skills?·How to Install

Install with 🐟 Skill.Fish

npx skillfish add hgeldenhuys/claude-code-sdk testing-patterns

For use in Claude.ai and ChatGPT

Download Skill