Mocking Strategies

Effective mocking patterns for Gauzy tests.

Repository Mocking

const mockRepository = {
  findOne: jest.fn(),
  find: jest.fn(),
  save: jest.fn(),
  delete: jest.fn(),
  count: jest.fn(),
  createQueryBuilder: jest.fn(() => ({
    where: jest.fn().mockReturnThis(),
    andWhere: jest.fn().mockReturnThis(),
    getMany: jest.fn().mockResolvedValue([]),
    getCount: jest.fn().mockResolvedValue(0),
  })),
};

Service Mocking

const mockEmployeeService = {
  findAll: jest.fn().mockResolvedValue({ items: [], total: 0 }),
  findOneByIdString: jest.fn(),
  create: jest.fn(),
  update: jest.fn(),
  delete: jest.fn(),
};

// In module
providers: [{ provide: EmployeeService, useValue: mockEmployeeService }];

HTTP Mocking

// Angular HTTP testing
import {
  HttpClientTestingModule,
  HttpTestingController,
} from "@angular/common/http/testing";

let httpMock: HttpTestingController;

it("should fetch employees", () => {
  service.getEmployees().subscribe((data) => {
    expect(data.length).toBe(2);
  });

  const req = httpMock.expectOne("/api/employee");
  req.flush([{ id: "1" }, { id: "2" }]);
});

Request Context Mocking

const mockRequest = {
  user: { id: "user-uuid", tenantId: "tenant-uuid" },
  headers: { authorization: "Bearer token" },
};

const mockRequestContext = {
  currentTenantId: jest.fn().mockReturnValue("tenant-uuid"),
  currentUserId: jest.fn().mockReturnValue("user-uuid"),
};

When to Mock vs. Use Real

Use Mock	Use Real
External HTTP APIs	Database (in integration)
Email services	Validation pipes
File storage providers	DTO transformations
Payment gateways	Business logic calculations

Related Pages

• Unit Testing Guide — unit tests
• Test Fixtures — test data
• Testing Guards — guard tests