agentic-dev/docs/guides/testing-strategy.md

Testing Strategy

Test Layers

Layer	Tool	What to Test
Entities	Vitest (unit)	Zod schema validation, error classes
Use Cases	Vitest (unit)	Business logic with mock implementations via DI
Controllers	Vitest (unit)	Input validation, use case delegation, error mapping
Infrastructure	Vitest (integration)	Real DB via test containers, Payload API calls
UI Components	Vitest + Storybook	Rendering, props, accessibility
Full App	Playwright (E2E)	User flows across both Next.js and TanStack Start

Running Tests

pnpm test                              # All tests via Turborepo
cd packages/core && pnpm vitest run    # Core unit tests only
cd packages/core && pnpm vitest watch  # Core tests in watch mode

Test Pattern (DI Container)

All tests that use the DI container must initialize and destroy it:

import "reflect-metadata";
import { beforeEach, afterEach } from "vitest";
import { initializeContainer, destroyContainer } from "@/di/container.js";

beforeEach(() => { initializeContainer(); });
afterEach(() => { destroyContainer(); });

This ensures each test gets fresh mock instances (singleton scope resets).

Test File Location

• Core tests: packages/core/tests/unit/{use-cases,controllers}/{domain}/
• UI tests: co-located next to component (*.test.tsx)
• E2E tests: tests/e2e/