test-generator_skill

Overview

This skill generates comprehensive unit, integration, and end-to-end tests tailored to your code and chosen framework. It produces tests with edge cases, realistic fixtures, mocks, and clear Arrange-Act-Assert structure to support TDD and improve coverage. It targets multiple ecosystems including JavaScript/TypeScript, Python, Java, Go, and more.

How this skill works

Provide the function, class, API endpoint, or requirements and specify the target framework. The skill analyzes the code or spec, detects boundary and error cases, creates mocks for external dependencies, and emits runnable test suites with assertions and comments explaining intent. It also generates test data factories, fixtures, and CI-friendly structure for coverage optimization.

When to use it

• Writing tests for new or existing functions, classes, or modules
• Creating API integration tests and error-case scenarios
• Authoring E2E flows for critical user journeys
• Practicing Test-Driven Development (generate tests from requirements)
• Preparing mocks for external services and dependency isolation

Best practices

• Prefer many fast unit tests and keep E2E tests focused on critical flows
• Use generated mocks and fixtures to isolate external dependencies
• Follow Arrange-Act-Assert structure for clarity and maintainability
• Aim for meaningful assertions, not just increasing coverage numbers
• Keep tests deterministic by avoiding time- and network-dependent logic

Example use cases

• Generate Jest unit tests for a currency formatter with edge cases and error handling
• Create pytest integration tests for a POST /api/orders endpoint including auth and DB error handling
• Produce Playwright E2E scripts for signup and login flows with validation checks
• Auto-generate Mockito-based Java tests that verify repository and email interactions
• Build test data factories and fixtures for repeatable test scenarios