test(api): add unit tests for MCP, Inquiries, and Leads modules

Increase test file coverage to ≥50% for three under-tested modules:

- MCP: +1 test (mcp.module.spec.ts) → 2/2 files covered (100%)
- Inquiries: +4 tests (events, repository contract, prisma repo, DTOs)
  → 10/18 files covered (55.6%)
- Leads: +4 tests (events, repository contract, prisma repo, DTOs)
  → 12/22 files covered (54.5%)

All 225 test files pass with 1353 tests total.

Co-Authored-By: Paperclip <noreply@paperclip.ing>

apps/api/src/modules/inquiries/domain/__tests__/inquiry-events.spec.ts

@@ -0,0 +1,52 @@
+import { InquiryCreatedEvent } from '../events/inquiry-created.event';
+import { InquiryReadEvent } from '../events/inquiry-read.event';
+
+describe('InquiryCreatedEvent', () => {
+  it('stores the aggregate id, listing id, and user id', () => {
+    const event = new InquiryCreatedEvent('inq-1', 'listing-1', 'user-1');
+
+    expect(event.aggregateId).toBe('inq-1');
+    expect(event.listingId).toBe('listing-1');
+    expect(event.userId).toBe('user-1');
+  });
+
+  it('has the correct event name', () => {
+    const event = new InquiryCreatedEvent('inq-1', 'listing-1', 'user-1');
+
+    expect(event.eventName).toBe('inquiry.created');
+  });
+
+  it('records the occurred timestamp', () => {
+    const before = new Date();
+    const event = new InquiryCreatedEvent('inq-1', 'listing-1', 'user-1');
+    const after = new Date();
+
+    expect(event.occurredAt.getTime()).toBeGreaterThanOrEqual(before.getTime());
+    expect(event.occurredAt.getTime()).toBeLessThanOrEqual(after.getTime());
+  });
+});
+
+describe('InquiryReadEvent', () => {
+  it('stores the aggregate id, listing id, and user id', () => {
+    const event = new InquiryReadEvent('inq-1', 'listing-1', 'user-1');
+
+    expect(event.aggregateId).toBe('inq-1');
+    expect(event.listingId).toBe('listing-1');
+    expect(event.userId).toBe('user-1');
+  });
+
+  it('has the correct event name', () => {
+    const event = new InquiryReadEvent('inq-1', 'listing-1', 'user-1');
+
+    expect(event.eventName).toBe('inquiry.read');
+  });
+
+  it('records the occurred timestamp', () => {
+    const before = new Date();
+    const event = new InquiryReadEvent('inq-1', 'listing-1', 'user-1');
+    const after = new Date();
+
+    expect(event.occurredAt.getTime()).toBeGreaterThanOrEqual(before.getTime());
+    expect(event.occurredAt.getTime()).toBeLessThanOrEqual(after.getTime());
+  });
+});

apps/api/src/modules/inquiries/domain/__tests__/inquiry-repository-contract.spec.ts

@@ -0,0 +1,18 @@
+import { INQUIRY_REPOSITORY } from '../repositories/inquiry.repository';
+
+describe('Inquiry Repository Contract', () => {
+  describe('INQUIRY_REPOSITORY symbol', () => {
+    it('is a unique symbol', () => {
+      expect(typeof INQUIRY_REPOSITORY).toBe('symbol');
+    });
+
+    it('has a descriptive string representation', () => {
+      expect(INQUIRY_REPOSITORY.toString()).toBe('Symbol(INQUIRY_REPOSITORY)');
+    });
+
+    it('is not equal to another symbol with the same description', () => {
+      const anotherSymbol = Symbol('INQUIRY_REPOSITORY');
+      expect(INQUIRY_REPOSITORY).not.toBe(anotherSymbol);
+    });
+  });
+});

apps/api/src/modules/inquiries/infrastructure/__tests__/prisma-inquiry.repository.spec.ts

@@ -0,0 +1,233 @@
+import { InquiryEntity } from '../../domain/entities/inquiry.entity';
+import { PrismaInquiryRepository } from '../repositories/prisma-inquiry.repository';
+
+describe('PrismaInquiryRepository', () => {
+  let repository: PrismaInquiryRepository;
+  let mockPrisma: {
+    inquiry: {
+      findUnique: ReturnType<typeof vi.fn>;
+      create: ReturnType<typeof vi.fn>;
+      update: ReturnType<typeof vi.fn>;
+      findMany: ReturnType<typeof vi.fn>;
+      count: ReturnType<typeof vi.fn>;
+    };
+  };
+
+  beforeEach(() => {
+    mockPrisma = {
+      inquiry: {
+        findUnique: vi.fn(),
+        create: vi.fn(),
+        update: vi.fn(),
+        findMany: vi.fn(),
+        count: vi.fn(),
+      },
+    };
+    repository = new PrismaInquiryRepository(mockPrisma as any);
+  });
+
+  describe('findById', () => {
+    it('returns an InquiryEntity when found', async () => {
+      const now = new Date();
+      mockPrisma.inquiry.findUnique.mockResolvedValue({
+        id: 'inq-1',
+        listingId: 'listing-1',
+        userId: 'user-1',
+        message: 'Tôi muốn xem nhà',
+        phone: '0901234567',
+        isRead: false,
+        createdAt: now,
+      });
+
+      const result = await repository.findById('inq-1');
+
+      expect(result).toBeInstanceOf(InquiryEntity);
+      expect(result!.id).toBe('inq-1');
+      expect(result!.listingId).toBe('listing-1');
+      expect(result!.userId).toBe('user-1');
+      expect(result!.message).toBe('Tôi muốn xem nhà');
+      expect(result!.phone).toBe('0901234567');
+      expect(result!.isRead).toBe(false);
+    });
+
+    it('returns null when not found', async () => {
+      mockPrisma.inquiry.findUnique.mockResolvedValue(null);
+
+      const result = await repository.findById('nonexistent');
+
+      expect(result).toBeNull();
+    });
+  });
+
+  describe('save', () => {
+    it('creates a Prisma record from the entity', async () => {
+      mockPrisma.inquiry.create.mockResolvedValue(undefined);
+      const entity = InquiryEntity.createNew(
+        'inq-1',
+        'listing-1',
+        'user-1',
+        'Tôi muốn xem nhà',
+        '0901234567',
+      );
+
+      await repository.save(entity);
+
+      expect(mockPrisma.inquiry.create).toHaveBeenCalledWith({
+        data: {
+          id: 'inq-1',
+          listingId: 'listing-1',
+          userId: 'user-1',
+          message: 'Tôi muốn xem nhà',
+          phone: '0901234567',
+          isRead: false,
+        },
+      });
+    });
+
+    it('saves entity with null phone', async () => {
+      mockPrisma.inquiry.create.mockResolvedValue(undefined);
+      const entity = InquiryEntity.createNew(
+        'inq-2',
+        'listing-1',
+        'user-1',
+        'Cho tôi hỏi giá',
+        null,
+      );
+
+      await repository.save(entity);
+
+      const callData = mockPrisma.inquiry.create.mock.calls[0]![0].data;
+      expect(callData.phone).toBeNull();
+    });
+  });
+
+  describe('markAsRead', () => {
+    it('updates the isRead field to true', async () => {
+      mockPrisma.inquiry.update.mockResolvedValue(undefined);
+
+      await repository.markAsRead('inq-1');
+
+      expect(mockPrisma.inquiry.update).toHaveBeenCalledWith({
+        where: { id: 'inq-1' },
+        data: { isRead: true },
+      });
+    });
+  });
+
+  describe('findByListing', () => {
+    it('returns paginated results', async () => {
+      const now = new Date();
+      mockPrisma.inquiry.findMany.mockResolvedValue([
+        {
+          id: 'inq-1',
+          listingId: 'listing-1',
+          userId: 'user-1',
+          message: 'Xin chào',
+          phone: null,
+          isRead: false,
+          createdAt: now,
+          listing: { id: 'listing-1', property: { title: 'Căn hộ Quận 1' } },
+          user: { id: 'user-1', fullName: 'Nguyễn Văn A', phone: '0901234567' },
+        },
+      ]);
+      mockPrisma.inquiry.count.mockResolvedValue(1);
+
+      const result = await repository.findByListing('listing-1', 1, 20);
+
+      expect(result.data).toHaveLength(1);
+      expect(result.total).toBe(1);
+      expect(result.page).toBe(1);
+      expect(result.limit).toBe(20);
+      expect(result.totalPages).toBe(1);
+      expect(result.data[0]!.listingTitle).toBe('Căn hộ Quận 1');
+      expect(result.data[0]!.userName).toBe('Nguyễn Văn A');
+    });
+
+    it('caps limit at 100', async () => {
+      mockPrisma.inquiry.findMany.mockResolvedValue([]);
+      mockPrisma.inquiry.count.mockResolvedValue(0);
+
+      const result = await repository.findByListing('listing-1', 1, 200);
+
+      expect(result.limit).toBe(100);
+      expect(mockPrisma.inquiry.findMany).toHaveBeenCalledWith(
+        expect.objectContaining({ take: 100 }),
+      );
+    });
+
+    it('calculates correct skip for pagination', async () => {
+      mockPrisma.inquiry.findMany.mockResolvedValue([]);
+      mockPrisma.inquiry.count.mockResolvedValue(0);
+
+      await repository.findByListing('listing-1', 3, 10);
+
+      expect(mockPrisma.inquiry.findMany).toHaveBeenCalledWith(
+        expect.objectContaining({ skip: 20 }),
+      );
+    });
+  });
+
+  describe('findByAgent', () => {
+    it('returns paginated results for agent', async () => {
+      const now = new Date();
+      mockPrisma.inquiry.findMany.mockResolvedValue([
+        {
+          id: 'inq-1',
+          listingId: 'listing-1',
+          userId: 'user-1',
+          message: 'Xin chào',
+          phone: null,
+          isRead: true,
+          createdAt: now,
+          listing: { id: 'listing-1', property: { title: 'Nhà phố Quận 7' } },
+          user: { id: 'user-1', fullName: 'Trần Thị B', phone: '0902345678' },
+        },
+      ]);
+      mockPrisma.inquiry.count.mockResolvedValue(1);
+
+      const result = await repository.findByAgent('agent-1', 1, 20);
+
+      expect(result.data).toHaveLength(1);
+      expect(result.data[0]!.listingTitle).toBe('Nhà phố Quận 7');
+      expect(result.data[0]!.userName).toBe('Trần Thị B');
+      expect(result.data[0]!.isRead).toBe(true);
+    });
+
+    it('queries using listing.agentId filter', async () => {
+      mockPrisma.inquiry.findMany.mockResolvedValue([]);
+      mockPrisma.inquiry.count.mockResolvedValue(0);
+
+      await repository.findByAgent('agent-1', 1, 20);
+
+      expect(mockPrisma.inquiry.findMany).toHaveBeenCalledWith(
+        expect.objectContaining({
+          where: { listing: { agentId: 'agent-1' } },
+        }),
+      );
+    });
+  });
+
+  describe('countUnreadByAgent', () => {
+    it('returns the count of unread inquiries for the agent', async () => {
+      mockPrisma.inquiry.count.mockResolvedValue(5);
+
+      const result = await repository.countUnreadByAgent('agent-1');
+
+      expect(result).toBe(5);
+      expect(mockPrisma.inquiry.count).toHaveBeenCalledWith({
+        where: {
+          isRead: false,
+          listing: { agentId: 'agent-1' },
+        },
+      });
+    });
+
+    it('returns 0 when no unread inquiries exist', async () => {
+      mockPrisma.inquiry.count.mockResolvedValue(0);
+
+      const result = await repository.countUnreadByAgent('agent-1');
+
+      expect(result).toBe(0);
+    });
+  });
+});

apps/api/src/modules/inquiries/presentation/__tests__/inquiry-dto.spec.ts

@@ -0,0 +1,103 @@
+import 'reflect-metadata';
+import { CreateInquiryDto } from '../dto/create-inquiry.dto';
+import { ListInquiriesDto } from '../dto/list-inquiries.dto';
+
+describe('CreateInquiryDto', () => {
+  describe('validation metadata', () => {
+    it('has validation metadata on listingId property', () => {
+      const metadata = Reflect.getMetadata(
+        'swagger/apiModelProperties',
+        CreateInquiryDto.prototype,
+        'listingId',
+      );
+      expect(metadata).toBeDefined();
+      expect(metadata.description).toBe('ID of the listing');
+    });
+
+    it('has validation metadata on message property', () => {
+      const metadata = Reflect.getMetadata(
+        'swagger/apiModelProperties',
+        CreateInquiryDto.prototype,
+        'message',
+      );
+      expect(metadata).toBeDefined();
+      expect(metadata.description).toBe('Tin nhắn yêu cầu tư vấn');
+    });
+
+    it('has optional phone property metadata', () => {
+      const metadata = Reflect.getMetadata(
+        'swagger/apiModelProperties',
+        CreateInquiryDto.prototype,
+        'phone',
+      );
+      expect(metadata).toBeDefined();
+      expect(metadata.description).toBe('Số điện thoại liên hệ');
+    });
+  });
+
+  describe('property assignment', () => {
+    it('can assign all required properties', () => {
+      const dto = new CreateInquiryDto();
+      dto.listingId = 'listing-1';
+      dto.message = 'Tôi muốn xem nhà';
+
+      expect(dto.listingId).toBe('listing-1');
+      expect(dto.message).toBe('Tôi muốn xem nhà');
+    });
+
+    it('can assign optional phone', () => {
+      const dto = new CreateInquiryDto();
+      dto.phone = '0901234567';
+
+      expect(dto.phone).toBe('0901234567');
+    });
+
+    it('phone defaults to undefined when not assigned', () => {
+      const dto = new CreateInquiryDto();
+
+      expect(dto.phone).toBeUndefined();
+    });
+  });
+});
+
+describe('ListInquiriesDto', () => {
+  describe('validation metadata', () => {
+    it('has page property metadata', () => {
+      const metadata = Reflect.getMetadata(
+        'swagger/apiModelProperties',
+        ListInquiriesDto.prototype,
+        'page',
+      );
+      expect(metadata).toBeDefined();
+      expect(metadata.default).toBe(1);
+    });
+
+    it('has limit property metadata', () => {
+      const metadata = Reflect.getMetadata(
+        'swagger/apiModelProperties',
+        ListInquiriesDto.prototype,
+        'limit',
+      );
+      expect(metadata).toBeDefined();
+      expect(metadata.default).toBe(20);
+    });
+  });
+
+  describe('property assignment', () => {
+    it('can assign page and limit', () => {
+      const dto = new ListInquiriesDto();
+      dto.page = 2;
+      dto.limit = 50;
+
+      expect(dto.page).toBe(2);
+      expect(dto.limit).toBe(50);
+    });
+
+    it('page and limit default to undefined when not assigned', () => {
+      const dto = new ListInquiriesDto();
+
+      expect(dto.page).toBeUndefined();
+      expect(dto.limit).toBeUndefined();
+    });
+  });
+});