JavaScript Testing Patterns Comprehensive guide for implementing robust testing strategies in JavaScript/TypeScript applications using modern testing frameworks and best practices. When to Use This Skill - Setting up test infrastructure for new projects - Writing unit tests for functions and classes - Creating integration tests for APIs and services - Implementing end-to-end tests for user flows - Mocking external dependencies and APIs - Testing React, Vue, or other frontend components - Implementing test-driven development (TDD) - Setting up continuous testing in CI/CD pipelines Testing Fram…