Test/#2 server chat module 테스트 코드 추가

server/src/chat/chat.gateway.spec.ts

@@ -1,18 +1,99 @@
 import { Test, TestingModule } from '@nestjs/testing';
 import { ChatGateway } from './chat.gateway';
+import { ChatService } from './chat.service';
+import { BadRequestException, PlayerNotFoundException, RoomNotFoundException } from 'src/exceptions/game.exception';
+import { Socket } from 'socket.io';
 
 describe('ChatGateway', () => {
   let gateway: ChatGateway;
+  let mockSocket: Partial<Socket>;
+
+  const mockChatService = {
+    existsRoom: jest.fn(),
+    existsPlayer: jest.fn(),
+    sendMessage: jest.fn(),
+  };
 
   beforeEach(async () => {
     const module: TestingModule = await Test.createTestingModule({
-      providers: [ChatGateway],
+      providers: [ChatGateway, { provide: ChatService, useValue: mockChatService }],
     }).compile();
 
-    gateway = module.get<ChatGateway>(ChatGateway);
+    gateway = module.get(ChatGateway);
+
+    /**
+     * as unknown as 를 이용해 타입을 먼저 unknown으로 바꾼 다음,
+     * 원하는 타입에 type assertion을 한다.
+     */
+    mockSocket = {
+      handshake: { auth: { roomId: 'room1', playerId: 'player1' } },
+      data: {},
+      join: jest.fn(),
+      to: jest.fn().mockReturnThis(),
+      emit: jest.fn(),
+    } as unknown as Socket;
+  });
+
+  afterEach(() => {
+    jest.clearAllMocks();
+  });
+
+  describe('handleConnection 테스트', () => {
+    it('roomId가 null일 때 BadRequestException을 발생', () => {
+      mockSocket.handshake.auth = { roomId: null };
+
+      expect(() => gateway.handleConnection(mockSocket as Socket)).toThrow(BadRequestException);
+    });
+
+    it('playerId가 null일 때 BadRequestException을 발생', () => {
+      mockSocket.handshake.auth = { playerId: null };
+
+      expect(() => gateway.handleConnection(mockSocket as Socket)).toThrow(BadRequestException);
+    });
+
+    it('room이 존재하지 않을 때 RoomNotFoundException을 발생', () => {
+      mockChatService.existsRoom.mockReturnValue(false);
+
+      expect(() => gateway.handleConnection(mockSocket as Socket)).toThrow(RoomNotFoundException);
+      expect(mockChatService.existsRoom).toHaveBeenCalled();
+    });
+
+    it('플레이어가 룸에 존재하지 않을 때 PlayerNotFoundException을 발생', () => {
+      mockChatService.existsRoom.mockReturnValue(true);
+      mockChatService.existsPlayer.mockReturnValue(false);
+
+      expect(() => gateway.handleConnection(mockSocket as Socket)).toThrow(PlayerNotFoundException);
+      expect(mockChatService.existsPlayer).toHaveBeenCalled();
+    });
+
+    it('플레이어와 방이 정상적으로 할당되어 있을 때', () => {
+      mockChatService.existsRoom.mockReturnValue(true);
+      mockChatService.existsPlayer.mockReturnValue(true);
+
+      gateway.handleConnection(mockSocket as Socket);
+
+      expect(mockSocket.join).toHaveBeenCalled();
+      expect(mockSocket.data).toEqual({ roomId: 'room1', playerId: 'player1' });
+    });
   });
 
-  it('should be defined', () => {
-    expect(gateway).toBeDefined();
+  describe('handleSendMessage 테스트', () => {
+    it('데이터가 없을 때 BadRequestException을 발생', async () => {
+      mockSocket.data = {};
+
+      await expect(gateway.handleSendMessage(mockSocket as Socket, { message: 'hello world' })).rejects.toThrow(
+        BadRequestException,
+      );
+    });
+
+    it('정상적으로 메시지를 발신할 수 있을 때', async () => {
+      mockSocket.data = { roomId: 'room1', playerId: 'player1' };
+      mockChatService.sendMessage.mockResolvedValue({ message: 'hello world', sender: 'player1' });
+
+      await gateway.handleSendMessage(mockSocket as Socket, { message: 'hello world' });
+
+      expect(mockChatService.sendMessage).toHaveBeenCalled();
+      expect(mockSocket.to('room1').emit).toHaveBeenCalled();
+    });
   });
 });