我有服务：

export default class WorldService {

constructor(worldmodel) {
    this.worldmodel = worldmodel;
  }

  async getWorlds() {
    let resData = {};
    await this.worldmodel.find({},(err,worlds) => {
      resData = worlds;
    });
    return resData;
  }
}

我有一个猫鼬模型：

import mongoose from 'mongoose';

const worldSchema = mongoose.Schema({
  name: {
    type: String,required: true,},});

export default mongoose.model('World',worldSchema);

我想模拟Mongoose模型并测试名为getWorlds()的服务功能。我在项目中使用 Jest 作为测试框架。

我试图用Jest编写单元测试：

import Worldmodel from '../../../src/models/world';
import WorldService from '../../../src/services/world';

describe('When data is valid',() => {
  beforeAll(() => {
    jest.spyOn(Worldmodel,'find').mockReturnValue(Promise.resolve([
      { _id: '5dbff32e367a343830cd2f49',name: 'Earth',__v: 0 },{ _id: '5dbff89209dee20b18091ec3',name: 'Mars',]));
  });

  it('Should return entries',async () => {
    const worldService = new WorldService(Worldmodel);

    const expected = [
      { _id: '5dbff32e367a343830cd2f49',];
    await expect(worldService.getWorlds()).resolves.toEqual(expected);
  });
});

我得到一个失败的答案：

 FAIL  test/unit/services/world.test.js
  When data is valid
    × Should return entries (9ms)

  ● When data is valid › Should return entries

    expect(received).resolves.toEqual(expected) // deep equality

    Expected: [{"__v": 0,"_id": "5dbff32e367a343830cd2f49","name": "Earth"},{"__v": 0,"_id": "5dbff89209dee20b18091ec3","name": "Mars"}]
    Received: {}

如何在Jest中模拟猫鼬 find()函数？

P.s。我不想对 MongoDB 使用任何更高级别的测试框架，例如 mockgoose 。