public void OkShortUrl()
        {
            IPipelineActivity activity = new EntryPointRegisterPipelineActivity(null);
            DownloadContext   context  = BuildContext("https://youtu.be/PH0SqgTSocs");

            Assert.Throws <NullReferenceException>(() => {
                activity.ExecuteAsync(context).GetAwaiter().GetResult();
            });
        }
        public void NullAddress()
        {
            IPipelineActivity activity = new EntryPointRegisterPipelineActivity(null);
            DownloadContext   context  = BuildContext(null);

            Assert.Throws <ArgumentNullException>(() => {
                activity.ExecuteAsync(context).GetAwaiter().GetResult();
            });
        }
        public void Playlist()
        {
            IPipelineActivity activity = new EntryPointRegisterPipelineActivity(null);
            DownloadContext   context  = BuildContext("https://www.youtube.com/watch?v=gFTE__qOMqI&t=306s&index=1&list=PLbDr6zG2yjZPD-FvY6cBQQAB8j7tjXD11");

            Assert.Throws <InvalidOperationException>(() => {
                activity.ExecuteAsync(context).GetAwaiter().GetResult();
            });
        }
        public void GenericGoogleAddress()
        {
            IPipelineActivity activity = new EntryPointRegisterPipelineActivity(null);
            DownloadContext   context  = BuildContext("https://www.google.com");

            Assert.Throws <InvalidOperationException>(() => {
                activity.ExecuteAsync(context).GetAwaiter().GetResult();
            });
        }
    public void OkLongUrl()
    {
        IPipelineActivity activity = new EntryPointRegisterPipelineActivity(null);
        Download          download = this.BuildContext("https://www.youtube.com/watch?v=PH0SqgTSocs");

        Assert.Throws <NullReferenceException>(() =>
        {
            activity.ExecuteAsync(download).GetAwaiter().GetResult();
        });
    }