export module FirstModule {
    export class firstClass {
        id:number;
        name:string;
    }
}

import { FirstModule } from "./first";

describe('example test', function () {
  let _first
  beforeEach(() => {
    _first = new FirstModule.firstClass();
  })

  it('module defined', function () {
    expect(_first).toBeDefined();
  });

files: [
  '*.spec.ts',
  '*.ts' //this thing is missing
]