Neo4j Memory Server

/** * MCP Database Handler Tests - Production Integration * Single responsibility: Test database switching operations * * Test Coverage Target: 90%+ (Critical MCP functionality) */ import { describe, it, expect, vi, beforeEach } from 'vitest'; import { McpDatabaseHandler } from '../../../src/application/mcp-handlers/mcp-database-handler'; import { DIContainer } from '../../../src/container/di-container'; // Mock DIContainer to avoid database dependencies vi.mock('../../../src/container/di-container'); describe('McpDatabaseHandler - Database Operations', () => { let handler: McpDatabaseHandler; let mockContainer: vi.Mocked<DIContainer>; let mockDatabaseManager: any; beforeEach(() => { mockDatabaseManager = { switchDatabase: vi.fn() }; mockContainer = { initializeDatabase: vi.fn().mockResolvedValue(undefined), getDatabaseManager: vi.fn().mockReturnValue(mockDatabaseManager) } as any; (DIContainer.getInstance as any).mockReturnValue(mockContainer); handler = new McpDatabaseHandler(); }); describe('handleDatabaseSwitch', () => { it('should successfully switch to existing database', async () => { // Arrange const databaseName = 'test-database'; const expectedResult = { previousDatabase: 'neo4j', currentDatabase: 'test-database', created: false }; mockDatabaseManager.switchDatabase.mockResolvedValue(expectedResult); // Act const result = await handler.handleDatabaseSwitch(databaseName); // Assert expect(mockContainer.getDatabaseManager).toHaveBeenCalled(); expect(mockDatabaseManager.switchDatabase).toHaveBeenCalledWith(databaseName); expect(result).toEqual(expectedResult); }); it('should create new database when it does not exist', async () => { // Arrange const databaseName = 'new-project-db'; const expectedResult = { previousDatabase: 'neo4j', currentDatabase: 'new-project-db', created: true }; mockDatabaseManager.switchDatabase.mockResolvedValue(expectedResult); // Act const result = await handler.handleDatabaseSwitch(databaseName); // Assert expect(mockDatabaseManager.switchDatabase).toHaveBeenCalledWith(databaseName); expect(result.created).toBe(true); expect(result.currentDatabase).toBe(databaseName); }); it('should handle database switching errors gracefully', async () => { // Arrange const databaseName = 'invalid-db-name'; const errorMessage = 'Invalid database name: contains special characters'; mockDatabaseManager.switchDatabase.mockRejectedValue(new Error(errorMessage)); // Act & Assert await expect(handler.handleDatabaseSwitch(databaseName)) .rejects .toThrow('Invalid database name: invalid-db-name'); }); it('should handle network timeout errors', async () => { // Arrange const databaseName = 'timeout-db'; mockDatabaseManager.switchDatabase.mockRejectedValue(new Error('Connection timeout')); // Act & Assert await expect(handler.handleDatabaseSwitch(databaseName)) .rejects .toThrow("Database switch to 'timeout-db' failed: Connection timeout"); }); it('should handle permission errors', async () => { // Arrange const databaseName = 'restricted-db'; mockDatabaseManager.switchDatabase.mockRejectedValue(new Error('Access denied')); // Act & Assert await expect(handler.handleDatabaseSwitch(databaseName)) .rejects .toThrow("Database switch to 'restricted-db' failed: Access denied"); }); it('should handle empty database name', async () => { // Arrange const databaseName = ''; mockDatabaseManager.switchDatabase.mockRejectedValue(new Error('Database name cannot be empty')); // Act & Assert await expect(handler.handleDatabaseSwitch(databaseName)) .rejects .toThrow('Database name must be a non-empty string'); }); }); });