doc(samples) add unit tests for 13-mongo-typeorm

see nestjs#1539

Author: kiwikern

sample/13-mongo-typeorm/package-lock.json

@@ -34,6 +34,7 @@
     "@nestjs/schematics": "6.7.0",
     "@nestjs/testing": "6.8.5",
     "@types/express": "4.17.2",
+    "@types/jest": "^24.0.18",
     "@types/node": "12.12.5",
     "@types/supertest": "2.0.8",
     "jest": "24.9.0",
@@ -45,5 +46,17 @@
     "tsconfig-paths": "3.9.0",
     "tslint": "5.20.0",
     "typescript": "3.6.4"
+  },
+  "jest": {
+    "moduleFileExtensions": [
+      "js",
+      "json",
+      "ts"
+    ],
+    "rootDir": "src",
+    "testRegex": ".spec.ts$",
+    "transform": {
+      "^.+\\.(t|j)s$": "ts-jest"
+    }
   }
 }

sample/13-mongo-typeorm/package.json

@@ -0,0 +1,31 @@
+import { Test } from '@nestjs/testing';
+import { PhotoController } from './photo.controller';
+import { PhotoService } from './photo.service';
+
+describe('Photo Controller', () => {
+  let controller: PhotoController;
+  let service;
+
+  beforeAll(async () => {
+    const module = await Test.createTestingModule({
+      controllers: [PhotoController],
+      providers: [
+        {
+          provide: PhotoService,
+          useFactory: jest.fn(() => ({
+            findAll: jest.fn(),
+          })),
+        },
+      ],
+    }).compile();
+    controller = module.get<PhotoController>(PhotoController);
+    service = module.get(PhotoService);
+  });
+
+  it('should return all photos from the service', async () => {
+    service.findAll.mockReturnValueOnce([]);
+    expect(await controller.findAll()).toEqual([]);
+    expect(service.findAll).toHaveBeenCalledTimes(1);
+  });
+
+});

sample/13-mongo-typeorm/src/photo/photo.controller.spec.ts

@@ -0,0 +1,32 @@
+import { Test } from '@nestjs/testing';
+import { PhotoService } from './photo.service';
+import { getRepositoryToken } from '@nestjs/typeorm';
+import { Photo } from './photo.entity';
+
+describe('Photo Service', () => {
+  let service: PhotoService;
+  let repository;
+
+  beforeAll(async () => {
+    const module = await Test.createTestingModule({
+      controllers: [PhotoService],
+      providers: [
+        {
+          provide: getRepositoryToken(Photo),
+          useFactory: jest.fn(() => ({
+            find: jest.fn(),
+          })),
+        },
+      ],
+    }).compile();
+    service = module.get<PhotoService>(PhotoService);
+    repository = module.get(getRepositoryToken(Photo));
+  });
+
+  it('should return all photos from the repository', async () => {
+    repository.find.mockReturnValueOnce([]);
+    expect(await service.findAll()).toEqual([]);
+    expect(repository.find).toHaveBeenCalledTimes(1);
+  });
+
+});