unit-test

Unit testing with TDD follows a Red-Green-Refactor cycle: write a failing test first, implement minimal code to pass it, then refactor. Vitest executes these tests, isolating pure functions and logic from side effects to validate behavior systematically.

Arrange-Act-Assert is a standard unit-testing structure: arrange test data and mocks, act by calling the function, and assert the result. This pattern clarifies test intent and ensures each test validates one concept in isolation.

Mock boundaries by isolating external dependencies—APIs, databases, file systems—so tests focus on pure logic. Vitest mocking lets you control side effects and verify that your service functions and webhook handlers call dependencies correctly without executing them.

Yes. Unit testing excels at validating pure functions, service functions, and webhook handlers by running them in isolation with standard project scripts. This ensures repeatable execution and clear separation between calculations and side effects.

Avoid testing multiple concepts in one test, coupling tests to implementation details, and mixing side effects with pure logic. Unit testing requires clear test organization, one-concept-per-test discipline, and boundary mocking to maintain focused, maintainable tests.

Yes. Vitest provides fast execution for unit tests, supporting TDD workflows with the Red-Green-Refactor cycle. It integrates with standard project scripts, enabling repeatable test runs while maintaining test focus through proper mocking and isolation.