How does it handle external API dependencies?

The skill includes specific patterns for mocking global fetch, using module mocks, and implementing dependency injection to isolate your logic from external services.

Is this skill optimized for TypeScript?

Yes, all examples and configurations are provided with TypeScript best practices, including type-safe mocks and configuration files.

Can I use this for frontend component testing?

Absolutely. While it focuses on core logic, the mocking and integration patterns are directly applicable to Testing Library for React, Vue, and other frontend frameworks.

JavaScript Testing Patterns

Name: JavaScript Testing Patterns
Author: HermeticOrmus

byHermeticOrmus

Security & Testing

Implements comprehensive testing strategies using Jest, Vitest, and Testing Library for unit, integration, and end-to-end testing.

About

JavaScript Testing Patterns provides a robust framework for implementing high-quality test suites in modern JavaScript and TypeScript environments. It offers standardized configurations and implementation patterns for Jest and Vitest, covering everything from simple pure function validation to complex asynchronous service mocking. By providing architectural guidance on dependency injection and module spying, this skill helps developers build maintainable, testable codebases that support test-driven development (TDD) and reliable CI/CD pipelines.

Key Features

Integration and E2E testing workflows for async services
Standardized patterns for testing pure functions and classes
Production-ready configurations for Jest and Vitest
Dependency injection strategies for decoupled, testable code
0 GitHub stars
Advanced mocking techniques for external modules and APIs

Use Cases

Setting up a new testing infrastructure for a TypeScript project
Mocking complex external dependencies like email services or databases
Refactoring legacy code to include comprehensive unit and integration tests

About

Key Features

Integration and E2E testing workflows for async services
Standardized patterns for testing pure functions and classes
Production-ready configurations for Jest and Vitest
Dependency injection strategies for decoupled, testable code
0 GitHub stars
Advanced mocking techniques for external modules and APIs

Use Cases

Setting up a new testing infrastructure for a TypeScript project
Mocking complex external dependencies like email services or databases
Refactoring legacy code to include comprehensive unit and integration tests