From d0ab959c89a0adf6b86d35039b6a91349a5bedd1 Mon Sep 17 00:00:00 2001
From: Brennan <brecon@microsoft.com>
Date: Tue, 7 Jul 2020 19:50:31 -0700
Subject: [PATCH] TestServer registers NoopHostLifetime to avoid hangs from not
 disposing (#23761)

---
 src/Hosting/TestHost/src/NoopHostLifetime.cs  | 22 +++++++++++++++++++
 .../TestHost/src/WebHostBuilderExtensions.cs  |  2 ++
 src/Hosting/TestHost/test/TestServerTests.cs  | 15 +++++++++++++
 3 files changed, 39 insertions(+)
 create mode 100644 src/Hosting/TestHost/src/NoopHostLifetime.cs

diff --git a/src/Hosting/TestHost/src/NoopHostLifetime.cs b/src/Hosting/TestHost/src/NoopHostLifetime.cs
new file mode 100644
index 0000000000..a449babaae
--- /dev/null
+++ b/src/Hosting/TestHost/src/NoopHostLifetime.cs
@@ -0,0 +1,22 @@
+// Copyright (c) .NET Foundation. All rights reserved.
+// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
+
+using System.Threading;
+using System.Threading.Tasks;
+using Microsoft.Extensions.Hosting;
+
+namespace Microsoft.AspNetCore.TestHost
+{
+    internal class NoopHostLifetime : IHostLifetime
+    {
+        public Task StopAsync(CancellationToken cancellationToken)
+        {
+            return Task.CompletedTask;
+        }
+
+        public Task WaitForStartAsync(CancellationToken cancellationToken)
+        {
+            return Task.CompletedTask;
+        }
+    }
+}
\ No newline at end of file
diff --git a/src/Hosting/TestHost/src/WebHostBuilderExtensions.cs b/src/Hosting/TestHost/src/WebHostBuilderExtensions.cs
index c2051497cd..ab7db21c5c 100644
--- a/src/Hosting/TestHost/src/WebHostBuilderExtensions.cs
+++ b/src/Hosting/TestHost/src/WebHostBuilderExtensions.cs
@@ -8,6 +8,7 @@ using System.Net.Http;
 using Microsoft.AspNetCore.Hosting;
 using Microsoft.AspNetCore.Hosting.Server;
 using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Extensions.Hosting;
 
 namespace Microsoft.AspNetCore.TestHost
 {
@@ -17,6 +18,7 @@ namespace Microsoft.AspNetCore.TestHost
         {
             return builder.ConfigureServices(services =>
             {
+                services.AddSingleton<IHostLifetime, NoopHostLifetime>();
                 services.AddSingleton<IServer, TestServer>();
             });
         }
diff --git a/src/Hosting/TestHost/test/TestServerTests.cs b/src/Hosting/TestHost/test/TestServerTests.cs
index d05618cb26..0ffaf8b8b4 100644
--- a/src/Hosting/TestHost/test/TestServerTests.cs
+++ b/src/Hosting/TestHost/test/TestServerTests.cs
@@ -79,6 +79,21 @@ namespace Microsoft.AspNetCore.TestHost
             Assert.Equal(HttpStatusCode.NotFound, response.StatusCode);
         }
 
+        [Fact]
+        public async Task UseTestServerRegistersNoopHostLifetime()
+        {
+            using var host = await new HostBuilder()
+                .ConfigureWebHost(webBuilder =>
+                {
+                    webBuilder
+                        .UseTestServer()
+                        .Configure(app => { });
+                })
+                .StartAsync();
+
+            Assert.IsType<NoopHostLifetime>(host.Services.GetService<IHostLifetime>());
+        }
+
         [Fact]
         public void CreateWithDelegate()
         {