public async Task TestWriteHost()
        {
            using (var client = new PSClient())
            {
                await client.OpenAsync(PSConnectionInfo.CreateLocalConnection());
                string v = string.Empty;
                client.HostUI.WriteCallback = (s, fg, bg, c) =>
                {
                    if (s == PSOutputStream.Default)
                    {
                        v += c;
                    }
                };
                await client.InvokeScriptAsync("Write-Host \"Hello World\";");

                Assert.AreEqual("Hello World", v.Trim());
                Assert.IsTrue(v.EndsWith("\n"));

                // Also test multi-close
                await client.CloseAsync();
                await client.CloseAsync();
                await client.CloseAsync();
            }
        }