integration-tests

What problem does it solve? Unit tests with mocked dependencies cannot prove that modules are wired together correctly, that HTTP endpoints return proper status codes, or that frontend data flows work end to end. This Skill provides patterns for writing true integration tests that exercise real module graphs and network-level behavior. ## Core Features & Use Cases - API Integration Testing: Patterns for testing NestJS modules with supertest and TestingModule, covering CRUD roundtrips, validation errors, auth guards, and cross-module interactions. - Frontend Integration Testing: Patterns for testing React hooks and data layers with MSW and Testing Library, intercepting real HTTP calls at the network level. - Test Checklists: Concrete scenario tables covering status codes (400, 401, 404, 500), roundtrips, error propagation, and empty states. - Use Case: After creating a new Task API module, use this Skill to generate integration tests that verify POST creates a record, GET reads it back, DELETE removes it, and invalid input returns 400. ## Quick Start Write integration tests for my new NestJS task module covering create, read, delete roundtrips and validation error cases.