CLI Testing Library

CLI Testing Library provides a set of simple and complete utilities for testing command-line interface (CLI) applications, encouraging good testing practices by focusing on user interaction and observable output rather than internal implementation details. Inspired by the popular React Testing Library, it helps developers simulate user input and assert on console output (stdout, stderr). The library is currently at version 3.0.1, released in January 2025, and maintains an active development cadence with regular updates and major version bumps that introduce breaking changes and improvements. Its key differentiators include a focus on accessibility and user experience in tests, first-class TypeScript support, and integration with popular test runners like Jest and Vitest through dedicated extensions. It abstracts away the complexities of spawning and managing child processes, making CLI testing straightforward.