无法测试包含导入nestJS的类

// 假设需要测试的模块为 app.module.ts
import { Module } from '@nestjs/common';
import { CatsModule } from './cats/cats.module';
import { DogsModule } from './dogs/dogs.module';
import { PetsController } from './pets/pets.controller';

@Module({
  imports: [
    CatsModule,
    DogsModule,
  ],
  controllers: [PetsController],
})
export class AppModule {}

// app.module.spec.ts
import { Test } from '@nestjs/testing';
import { AppModule } from './app.module';
import { CatsModule } from './cats/cats.module';
import { DogsModule } from './dogs/dogs.module';
import { PetsController } from './pets/pets.controller';

describe('AppModule', () => {
  let appModule: AppModule;

  beforeEach(async () => {
    const module = await Test.createTestingModule({
      imports: [AppModule],
    }).compile();

    appModule = module.get<AppModule>(AppModule);
  });

  it('should be defined', () => {
    expect(appModule).toBeDefined();
  });

  it('should have cats module', () => {
    expect(appModule.imports).toContainEqual(CatsModule);
  });

  it('should have dogs module', () => {
    expect(appModule.imports).toContainEqual(DogsModule);
  });

  it('should have pets controller', () => {
    const controllers = appModule.controllers;
    const petsController = controllers.find((controller) => controller.constructor === PetsController);
    expect(petsController).toBeDefined();
  });
});