How to use the subscriptions-transport-ws.SubscriptionClient.prototype function in subscriptions-transport-ws

it('should call next with multiple results for subscription', done => {
    const results = [
      { data: { data: 'result1' } },
      { data: { data: 'result2' } },
    ];
    const client: any = {};
    client.__proto__ = SubscriptionClient.prototype;
    client.request = jest.fn(() => {
      const copy = [...results];
      return new Observable(observer => {
        observer.next(copy[0]);
        observer.next(copy[1]);
      });
    });

    const link = new WebSocketLink(client);

    execute(link, { query: subscription }).subscribe(data => {
      expect(client.request).toHaveBeenCalledTimes(1);
      expect(data).toEqual(results.shift());
      if (results.length === 0) {
        done();
      }

it('constructs', () => {
    const client: any = {};
    client.__proto__ = SubscriptionClient.prototype;
    expect(() => new WebSocketLink(client)).not.toThrow();
  });