MCP Debugger

# tests/unit/implementations/network-manager-impl.test.ts @source-hash: 404a514014ac913c @generated: 2026-02-10T00:41:33Z ## Purpose Unit test suite for NetworkManagerImpl class using Vitest testing framework. Tests network server creation and port discovery functionality with comprehensive mocking of Node.js net module. ## Key Test Structure - **Test Suite**: `NetworkManagerImpl` (L39-188) - Tests for `createServer` method (L54-69) - Tests for `findFreePort` method (L71-187) ## Mock Infrastructure - **mockServer**: Comprehensive mock object (L9-29) implementing full Node.js Server interface with all EventEmitter methods - **net module mock**: Mocks `net.createServer` to return mockServer (L32-37) - **beforeEach setup**: Resets all mocks and clears server state (L42-52) ## Test Coverage ### createServer Tests (L54-69) - **Basic functionality**: Verifies server creation and net.createServer invocation (L55-60) - **Error handling**: Tests exception propagation during server creation (L62-68) ### findFreePort Tests (L71-187) - **Successful port discovery**: Tests complete flow with mock server lifecycle (L72-99) - Mocks server.listen with port 0 and callback execution - Mocks server.address returning port number - Verifies server cleanup with unref() and close() - **Listen error handling**: Tests server error event propagation (L101-114) - **Invalid address handling**: Tests string address format rejection (L116-136) - **Null address handling**: Tests null address rejection (L138-158) - **Resource cleanup verification**: Tests proper server cleanup on success (L160-186) ## Mock Patterns - Uses `process.nextTick()` for asynchronous callback simulation - Implements conditional callback execution based on parameter presence - Comprehensive EventEmitter method mocking for complete interface coverage - Type assertions using `as any` for TypeScript compatibility with mocks ## Dependencies - Vitest testing framework with describe/it/expect/beforeEach/vi - Node.js net module (mocked) - NetworkManagerImpl from production code ## Test Architecture - Isolation through vi.clearAllMocks() in beforeEach - Complete interface mocking to prevent real network operations - Async/await pattern for promise-based method testing - Error simulation through mock implementation switching