angularjs – ‘IAngularStatic’类型中不存在属性’mock’

import {} from 'jasmine';
import * as angular from 'angular';
import {StrategyTables} from "./strategyTables.component";
import {StrategyTablesService} from "./strategyTables.service";
import {Router} from "@angular/router";
import {Location } from '@angular/common';
import {inject,async,TestBed} from '@angular/core/testing';
describe('strategyTables.component',() => {

  class MockstrategyService extends StrategyTablesService{
    getContactById(id:number){
      return{
        "name": "lee"
      };
    }

  }
  beforeEach(() => {
    angular.mock.module(($provide) => {
      TestBed.configureTestingModule({
        providers: [
          $provide.value(StrategyTablesService,{ useClass:MockstrategyService })
      ]
    });
    });
  });