typescript-unit-testing

Setting up Jest unit testing in TypeScript requires installing dependencies like `@nestjs/testing`, `jest`, and `ts-jest`, then configuring the test infrastructure. This Skill provides the comprehensive tooling and setup guidance needed to initialize the environment.

Writing unit tests for NestJS components involves adhering to the AAA pattern and applying assertion best practices. This Skill provides comprehensive guidance for creating new tests specifically for services and controllers to ensure robust, maintainable TypeScript code.

Slow test execution and hanging often stem from open handles in your test suite. This Skill helps you systematically optimize test performance and reliability by identifying and fixing open handles while tuning the setup process.

Debugging failing unit tests in TypeScript requires systematically diagnosing and fixing each failing test one by one. This Skill streamlines the entire debugging process for NestJS projects using Jest, ensuring robust and maintainable code.

Yes, you can analyze code coverage for TypeScript unit tests using `ts-jest` and `@types/jest`. This Skill provides comprehensive guidance on coverage analysis alongside dependency management and assertion best practices to optimize your testing workflow.

This Skill works for both new setups and existing configurations by providing comprehensive guidance on dependency management and optimization. It addresses common issues like open handles and slow execution to improve test reliability across any TypeScript NestJS project.