test: add comprehensive unit tests for core services

Added unit tests for the `api-keys`, `auth`, `categories`, `contents`, `favorites`, `media`, and `purge` services to improve test coverage and ensure core functionality integrity.

backend/src/reports/reports.service.spec.ts

@@ -0,0 +1,88 @@
+import { Test, TestingModule } from "@nestjs/testing";
+import { DatabaseService } from "../database/database.service";
+import { CreateReportDto } from "./dto/create-report.dto";
+import { ReportsService } from "./reports.service";
+
+describe("ReportsService", () => {
+	let service: ReportsService;
+
+	const mockDb = {
+		insert: jest.fn(),
+		values: jest.fn(),
+		returning: jest.fn(),
+		select: jest.fn(),
+		from: jest.fn(),
+		orderBy: jest.fn(),
+		limit: jest.fn(),
+		offset: jest.fn(),
+		update: jest.fn(),
+		set: jest.fn(),
+		where: jest.fn(),
+	};
+
+	beforeEach(async () => {
+		jest.clearAllMocks();
+
+		const chain = {
+			insert: jest.fn().mockReturnThis(),
+			values: jest.fn().mockReturnThis(),
+			returning: jest.fn().mockReturnThis(),
+			select: jest.fn().mockReturnThis(),
+			from: jest.fn().mockReturnThis(),
+			orderBy: jest.fn().mockReturnThis(),
+			limit: jest.fn().mockReturnThis(),
+			offset: jest.fn().mockReturnThis(),
+			update: jest.fn().mockReturnThis(),
+			set: jest.fn().mockReturnThis(),
+			where: jest.fn().mockReturnThis(),
+		};
+
+		const mockImplementation = () => Object.assign(Promise.resolve([]), chain);
+		for (const mock of Object.values(chain)) {
+			mock.mockImplementation(mockImplementation);
+		}
+		Object.assign(mockDb, chain);
+
+		const module: TestingModule = await Test.createTestingModule({
+			providers: [
+				ReportsService,
+				{ provide: DatabaseService, useValue: { db: mockDb } },
+			],
+		}).compile();
+
+		service = module.get<ReportsService>(ReportsService);
+	});
+
+	it("should be defined", () => {
+		expect(service).toBeDefined();
+	});
+
+	describe("create", () => {
+		it("should create a report", async () => {
+			const reporterId = "u1";
+			const data: CreateReportDto = { contentId: "c1", reason: "spam" };
+			mockDb.returning.mockResolvedValue([{ id: "r1", ...data, reporterId }]);
+
+			const result = await service.create(reporterId, data);
+
+			expect(result.id).toBe("r1");
+			expect(mockDb.insert).toHaveBeenCalled();
+		});
+	});
+
+	describe("findAll", () => {
+		it("should return reports", async () => {
+			mockDb.offset.mockResolvedValue([{ id: "r1" }]);
+			const result = await service.findAll(10, 0);
+			expect(result).toHaveLength(1);
+		});
+	});
+
+	describe("updateStatus", () => {
+		it("should update report status", async () => {
+			mockDb.returning.mockResolvedValue([{ id: "r1", status: "resolved" }]);
+			const result = await service.updateStatus("r1", "resolved");
+			expect(result[0].status).toBe("resolved");
+		});
+	});
+});