错误“可以加载实例”单元测试茉莉花

如何解决错误“可以加载实例”单元测试茉莉花

我的组件电子邮件：

 import { Component,AfterViewInit } from '@angular/core';
 
 @Component({   selector: 'app-email_conf',templateUrl:
 './email_conf.component.html' }) export class Email_confComponent
 implements AfterViewInit {
 
   constructor() { }
 
   ngAfterViewInit(): void {
     document.getElementById('body').classList.remove('pag_login');
     document.getElementById('body').classList.add('pag_inicial');   } }

和我的规格

import { ComponentFixture,Testbed } from '@angular/core/testing';
import { NO_ERRORS_SCHEMA } from '@angular/core'; import {
RouterTestingModule } from '@angular/router/testing'; import {
Email_confComponent } from './email_conf.component';
 
describe('Email_confComponent',() => {   let component:
Email_confComponent;   let fixture:
ComponentFixture<Email_confComponent>;
 
  beforeEach(() => {
    Testbed.configureTestingModule({
      imports: [RouterTestingModule],schemas: [NO_ERRORS_SCHEMA],declarations: [Email_confComponent],});
    fixture = Testbed.createComponent(Email_confComponent);
    component = fixture.componentInstance;   
  });

  it('can load instance',() => {
    expect(component).toBeTruthy();   
   }); 
  });

当运行测试返回“可以加载实例”时，我无法弄清楚我做错了什么，有人可以帮助我吗？