Как создать PointerEvent?

нужно протестировать метод

private stopSliding(event: PointerEvent): void {
  const { pointerId } = event;
  const target = event.target as HTMLElement;
  target.onpointermove = null;
  target.releasePointerCapture(pointerId);
}

пишу тест

describe('private stopSliding', () => {
  test('', () => {
    const downEvent = new PointerEvent('pointerdown', {
      pointerId: 1,
      bubbles: true,
      cancelable: true,
      clientX: 150,
      clientY: 150,
    });

    const view = new View('range-slider', settings);
    view.from.element.dispatchEvent(downEvent);
    const result = view['stopSliding'](downEvent);
  });
});

получаю ошибку TypeError: Failed to execute 'dispatchEvent' on 'EventTarget': parameter 1 is not of type 'Event'

Upd: добавил полифил

export class PointerEvent extends MouseEvent {
  public height?: number;
  public isPrimary?: boolean;
  public pointerId?: number;
  public pointerType?: string;
  public pressure?: number;
  public tangentialPressure?: number;
  public tiltX?: number;
  public tiltY?: number;
  public twist?: number;
  public width?: number;

  constructor(type: string, params: PointerEventInit = {}) {
    super(type, params);
    this.pointerId = params.pointerId;
    this.width = params.width;
    this.height = params.height;
    this.pressure = params.pressure;
    this.tangentialPressure = params.tangentialPressure;
    this.tiltX = params.tiltX;
    this.tiltY = params.tiltY;
    this.pointerType = params.pointerType;
    this.isPrimary = params.isPrimary;
  }
  public ReleasePointerCapture(value);
}
global.PointerEvent = PointerEvent as any;

получил ошибку TypeError: target.releasePointerCapture is not a function