fix(billing): add unit tests for billing service to meet coverage threshold

Global statement coverage was 79.67% (threshold: 80%). Added comprehensive
unit tests for createCheckout, createPortalSession, and getSubscription
covering all branches (stripe not configured, no subscription, existing
subscription without/with customer).

Author: PierreBrisorgueil

modules/billing/tests/billing.service.unit.tests.js

@@ -0,0 +1,251 @@
+/**
+ * Module dependencies.
+ */
+import { jest, beforeEach, afterEach } from '@jest/globals';
+
+/**
+ * Unit tests for billing service
+ */
+describe('Billing service unit tests:', () => {
+  let BillingService;
+  let mockStripeInstance;
+  let mockSubscriptionRepository;
+
+  const orgId = '507f1f77bcf86cd799439011';
+  const mockOrganization = { _id: orgId, name: 'Test Org' };
+
+  beforeEach(async () => {
+    jest.resetModules();
+
+    mockStripeInstance = {
+      customers: {
+        create: jest.fn().mockResolvedValue({ id: 'cus_new123' }),
+      },
+      checkout: {
+        sessions: {
+          create: jest.fn().mockResolvedValue({ url: 'https://checkout.stripe.com/session_123' }),
+        },
+      },
+      billingPortal: {
+        sessions: {
+          create: jest.fn().mockResolvedValue({ url: 'https://billing.stripe.com/portal_123' }),
+        },
+      },
+    };
+
+    jest.unstable_mockModule('stripe', () => ({
+      default: jest.fn(() => mockStripeInstance),
+    }));
+
+    mockSubscriptionRepository = {
+      findByOrganization: jest.fn(),
+      create: jest.fn(),
+      update: jest.fn(),
+    };
+
+    jest.unstable_mockModule('../repositories/billing.subscription.repository.js', () => ({
+      default: mockSubscriptionRepository,
+    }));
+  });
+
+  afterEach(() => {
+    jest.restoreAllMocks();
+  });
+
+  describe('createCheckout', () => {
+    test('should throw when stripe is not configured', async () => {
+      jest.unstable_mockModule('../../../config/index.js', () => ({
+        default: { stripe: {} },
+      }));
+
+      const mod = await import('../services/billing.service.js');
+      BillingService = mod.default;
+
+      await expect(BillingService.createCheckout(mockOrganization, 'price_123', 'http://ok', 'http://cancel')).rejects.toThrow(
+        'Stripe is not configured',
+      );
+    });
+
+    test('should throw when stripe config is null', async () => {
+      jest.unstable_mockModule('../../../config/index.js', () => ({
+        default: {},
+      }));
+
+      const mod = await import('../services/billing.service.js');
+      BillingService = mod.default;
+
+      await expect(BillingService.createCheckout(mockOrganization, 'price_123', 'http://ok', 'http://cancel')).rejects.toThrow(
+        'Stripe is not configured',
+      );
+    });
+
+    test('should create customer and subscription when none exists', async () => {
+      jest.unstable_mockModule('../../../config/index.js', () => ({
+        default: { stripe: { secretKey: 'sk_test_123' } },
+      }));
+
+      mockSubscriptionRepository.findByOrganization.mockResolvedValue(null);
+      mockSubscriptionRepository.create.mockResolvedValue({ stripeCustomerId: 'cus_new123' });
+
+      const mod = await import('../services/billing.service.js');
+      BillingService = mod.default;
+
+      const url = await BillingService.createCheckout(mockOrganization, 'price_123', 'http://ok', 'http://cancel');
+
+      expect(url).toBe('https://checkout.stripe.com/session_123');
+      expect(mockStripeInstance.customers.create).toHaveBeenCalledWith({
+        name: 'Test Org',
+        metadata: { organizationId: orgId },
+      });
+      expect(mockSubscriptionRepository.create).toHaveBeenCalledWith({
+        organization: orgId,
+        stripeCustomerId: 'cus_new123',
+      });
+    });
+
+    test('should update existing subscription without stripeCustomerId', async () => {
+      jest.unstable_mockModule('../../../config/index.js', () => ({
+        default: { stripe: { secretKey: 'sk_test_456' } },
+      }));
+
+      const existingSub = {
+        _id: 'sub_existing',
+        stripeCustomerId: null,
+        toObject: jest.fn().mockReturnValue({ _id: 'sub_existing', stripeCustomerId: null }),
+      };
+      mockSubscriptionRepository.findByOrganization.mockResolvedValue(existingSub);
+      mockSubscriptionRepository.update.mockResolvedValue({ stripeCustomerId: 'cus_new123' });
+
+      const mod = await import('../services/billing.service.js');
+      BillingService = mod.default;
+
+      const url = await BillingService.createCheckout(mockOrganization, 'price_123', 'http://ok', 'http://cancel');
+
+      expect(url).toBe('https://checkout.stripe.com/session_123');
+      expect(mockSubscriptionRepository.update).toHaveBeenCalledWith({
+        _id: 'sub_existing',
+        stripeCustomerId: 'cus_new123',
+      });
+    });
+
+    test('should use existing customer when subscription has stripeCustomerId', async () => {
+      jest.unstable_mockModule('../../../config/index.js', () => ({
+        default: { stripe: { secretKey: 'sk_test_789' } },
+      }));
+
+      mockSubscriptionRepository.findByOrganization.mockResolvedValue({
+        stripeCustomerId: 'cus_existing',
+      });
+
+      const mod = await import('../services/billing.service.js');
+      BillingService = mod.default;
+
+      const url = await BillingService.createCheckout(mockOrganization, 'price_123', 'http://ok', 'http://cancel');
+
+      expect(url).toBe('https://checkout.stripe.com/session_123');
+      expect(mockStripeInstance.customers.create).not.toHaveBeenCalled();
+      expect(mockStripeInstance.checkout.sessions.create).toHaveBeenCalledWith({
+        customer: 'cus_existing',
+        mode: 'subscription',
+        line_items: [{ price: 'price_123', quantity: 1 }],
+        success_url: 'http://ok',
+        cancel_url: 'http://cancel',
+      });
+    });
+  });
+
+  describe('createPortalSession', () => {
+    test('should throw when stripe is not configured', async () => {
+      jest.unstable_mockModule('../../../config/index.js', () => ({
+        default: { stripe: {} },
+      }));
+
+      const mod = await import('../services/billing.service.js');
+      BillingService = mod.default;
+
+      await expect(BillingService.createPortalSession(mockOrganization)).rejects.toThrow('Stripe is not configured');
+    });
+
+    test('should throw when no customer found', async () => {
+      jest.unstable_mockModule('../../../config/index.js', () => ({
+        default: { stripe: { secretKey: 'sk_test_portal1' } },
+      }));
+
+      mockSubscriptionRepository.findByOrganization.mockResolvedValue(null);
+
+      const mod = await import('../services/billing.service.js');
+      BillingService = mod.default;
+
+      await expect(BillingService.createPortalSession(mockOrganization)).rejects.toThrow(
+        'No Stripe customer found for this organization',
+      );
+    });
+
+    test('should throw when subscription has no stripeCustomerId', async () => {
+      jest.unstable_mockModule('../../../config/index.js', () => ({
+        default: { stripe: { secretKey: 'sk_test_portal2' } },
+      }));
+
+      mockSubscriptionRepository.findByOrganization.mockResolvedValue({ stripeCustomerId: null });
+
+      const mod = await import('../services/billing.service.js');
+      BillingService = mod.default;
+
+      await expect(BillingService.createPortalSession(mockOrganization)).rejects.toThrow(
+        'No Stripe customer found for this organization',
+      );
+    });
+
+    test('should return portal session URL when customer exists', async () => {
+      jest.unstable_mockModule('../../../config/index.js', () => ({
+        default: { stripe: { secretKey: 'sk_test_portal3' } },
+      }));
+
+      mockSubscriptionRepository.findByOrganization.mockResolvedValue({ stripeCustomerId: 'cus_portal' });
+
+      const mod = await import('../services/billing.service.js');
+      BillingService = mod.default;
+
+      const url = await BillingService.createPortalSession(mockOrganization);
+
+      expect(url).toBe('https://billing.stripe.com/portal_123');
+      expect(mockStripeInstance.billingPortal.sessions.create).toHaveBeenCalledWith({
+        customer: 'cus_portal',
+      });
+    });
+  });
+
+  describe('getSubscription', () => {
+    test('should return subscription for organization', async () => {
+      jest.unstable_mockModule('../../../config/index.js', () => ({
+        default: { stripe: { secretKey: 'sk_test_sub1' } },
+      }));
+
+      const mockSub = { organization: orgId, plan: 'pro' };
+      mockSubscriptionRepository.findByOrganization.mockResolvedValue(mockSub);
+
+      const mod = await import('../services/billing.service.js');
+      BillingService = mod.default;
+
+      const result = await BillingService.getSubscription(orgId);
+
+      expect(result).toEqual(mockSub);
+      expect(mockSubscriptionRepository.findByOrganization).toHaveBeenCalledWith(orgId);
+    });
+
+    test('should return null when no subscription exists', async () => {
+      jest.unstable_mockModule('../../../config/index.js', () => ({
+        default: { stripe: { secretKey: 'sk_test_sub2' } },
+      }));
+
+      mockSubscriptionRepository.findByOrganization.mockResolvedValue(null);
+
+      const mod = await import('../services/billing.service.js');
+      BillingService = mod.default;
+
+      const result = await BillingService.getSubscription(orgId);
+
+      expect(result).toBeNull();
+    });
+  });
+});