testing

Vitest and Testing Library provide a describe/it/expect pattern for writing unit tests. Create test files in src/__tests__/ using templates that cover functional requirements, apply assertions across frontend and backend modules, and configure coverage targets of 80% statements, 70% branches, and 80% functions.

Mock Firebase external services by setting up fake implementations in your test files before importing modules that depend on Firebase. This prevents actual API calls during testing and allows you to control mock behavior and verify interactions with Firebase methods.

Yes, Vitest supports unit, API, and component tests across frontend and backend code. You can apply the same describe/it/expect pattern and mocking strategies to test logic in different parts of your application using Testing Library assertions.

Aim for at least 80% statement coverage, 70% branch coverage, and 80% function coverage. These targets ensure your tests validate both the happy path and edge cases across your codebase, with slightly relaxed branch coverage accounting for complex conditional logic.

Apply the same mocking pattern used for Firebase to other external services: define mock implementations, replace real service calls with mocks in your test setup, and verify that your code interacts with mocks as expected using Testing Library assertions and Vitest spy functions.