test(auth): add unit tests for AuthGuard and AuthController with mocked dependencies

backend/src/auth/guards/auth.guard.spec.ts

@@ -0,0 +1,89 @@
+import { ExecutionContext, UnauthorizedException } from "@nestjs/common";
+import { ConfigService } from "@nestjs/config";
+import { Test, TestingModule } from "@nestjs/testing";
+import { getIronSession } from "iron-session";
+import { JwtService } from "../../crypto/services/jwt.service";
+import { AuthGuard } from "./auth.guard";
+
+jest.mock("jose", () => ({}));
+jest.mock("iron-session", () => ({
+	getIronSession: jest.fn(),
+}));
+
+describe("AuthGuard", () => {
+	let guard: AuthGuard;
+	let _jwtService: JwtService;
+	let _configService: ConfigService;
+
+	const mockJwtService = {
+		verifyJwt: jest.fn(),
+	};
+
+	const mockConfigService = {
+		get: jest.fn().mockReturnValue("session-password"),
+	};
+
+	beforeEach(async () => {
+		const module: TestingModule = await Test.createTestingModule({
+			providers: [
+				AuthGuard,
+				{ provide: JwtService, useValue: mockJwtService },
+				{ provide: ConfigService, useValue: mockConfigService },
+			],
+		}).compile();
+
+		guard = module.get<AuthGuard>(AuthGuard);
+		_jwtService = module.get<JwtService>(JwtService);
+		_configService = module.get<ConfigService>(ConfigService);
+	});
+
+	it("should return true for valid token", async () => {
+		const request = { user: null };
+		const context = {
+			switchToHttp: () => ({
+				getRequest: () => request,
+				getResponse: () => ({}),
+			}),
+		} as unknown as ExecutionContext;
+
+		(getIronSession as jest.Mock).mockResolvedValue({
+			accessToken: "valid-token",
+		});
+		mockJwtService.verifyJwt.mockResolvedValue({ sub: "user1" });
+
+		const result = await guard.canActivate(context);
+		expect(result).toBe(true);
+		expect(request.user).toEqual({ sub: "user1" });
+	});
+
+	it("should throw UnauthorizedException if no token", async () => {
+		const context = {
+			switchToHttp: () => ({
+				getRequest: () => ({}),
+				getResponse: () => ({}),
+			}),
+		} as ExecutionContext;
+
+		(getIronSession as jest.Mock).mockResolvedValue({});
+
+		await expect(guard.canActivate(context)).rejects.toThrow(
+			UnauthorizedException,
+		);
+	});
+
+	it("should throw UnauthorizedException if token invalid", async () => {
+		const context = {
+			switchToHttp: () => ({
+				getRequest: () => ({}),
+				getResponse: () => ({}),
+			}),
+		} as ExecutionContext;
+
+		(getIronSession as jest.Mock).mockResolvedValue({ accessToken: "invalid" });
+		mockJwtService.verifyJwt.mockRejectedValue(new Error("invalid"));
+
+		await expect(guard.canActivate(context)).rejects.toThrow(
+			UnauthorizedException,
+		);
+	});
+});