Typescript Unit Testing

The typescript-unit-testing skill enables AI agents to generate, execute, and verify unit tests specifically tailored for TypeScript codebases. It ensures that new or modified logic adheres to strict type safety requirements while maintaining comprehensive test coverage across functions and classes.

When to use it

• You need to validate business logic in a TypeScript backend service before merging code changes.
• An AI agent must automatically generate Jest or Vitest test cases for newly written utility functions.
• Your team requires regression testing to ensure recent refactors did not break existing type definitions.
• You want to enforce strict linting rules and mock dependencies within an automated CI/CD pipeline.

Key capabilities

• Generates syntactically correct TypeScript test files using popular frameworks like Jest or Vitest.
• Automatically infers types from source code to create accurate mocks and stubs.
• Validates edge cases based on defined interfaces and type constraints.
• Produces runnable test suites that can be integrated directly into build scripts.

Example prompts

• "Create a unit test suite for my calculateTax function using Jest, ensuring all input types are covered."
• "Generate mock data and test cases for a React component written in TypeScript that handles user authentication."
• "Write a Vitest test file that verifies error handling logic in my API endpoint when invalid JSON is received."

Tips & gotchas

Ensure your project has the necessary testing framework (e.g., @types/jest) installed before requesting test generation. The skill relies on accurate type definitions in your source code; missing or ambiguous types may result in incomplete test coverage.