单元测试KeyboardEvent返回“ isTrusted：false”和“无法读取null的属性'nextElementSibling'”

Question

我有一个通过keydown.enter触发的函数，它将专注于下一个可用元素，但是我无法通过测试接受我的假KeyboardEvent ...

@ViewChild('btnOne') btnOne: ElementRef<HTMLInputElement>;
@ViewChild('btnTwo') btnTwo: ElementRef<HTMLInputElement>;

myFunct(evt: KeyboardEvent) {
  const next = <HTMLElement>evt.srcElement.nextElementSibling;
  next.focus();
}

测试：

it('Should shift focus from btnOne to btnTwo', () => {
  const b1 = component.btnOne.nativeElement;
  const b2 = component.btnTwo.nativeElement;

  const button2 = {nodeName:'BUTTON'}
  const button1 = {nodeName:'BUTTON', nextElementSibling: button2};

  const evtObj = {'code': 'Enter', srcElement: button1);
  const kbEvent = new KeyboardEvent('keydown.enter', evtObj);

  focusSpy = spyOn(b2, 'focus'); // Spy on focus for 2nd button to be focused
  b1.focus(); // Manually apply focus to 1st button so it will progress from here

  component.myFunct(kbEvent); // I get the failures here (see below)

  expect(b2.focus).toHaveBeenCalled();

});

带有以下消息的测试错误：

  

TypeError：无法读取null的属性“ nextElementSibling”

我还打印了evt，因为它是从测试到函数本身的信息：

  

KeyboardEvent {isTrusted：false}

我已经搜索了isTrusted个问题并找到了this question，但是我无法用他们的答案解决问题...