Populate WebHost configuration with command line arguments if provided

MetaPackages.sln

@@ -1,6 +1,6 @@
 Microsoft Visual Studio Solution File, Format Version 12.00
 # Visual Studio 15
-VisualStudioVersion = 15.0.26923.0
+VisualStudioVersion = 15.0.27005.2
 MinimumVisualStudioVersion = 15.0.26730.03
 Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "src", "src", "{ED834E68-51C3-4ADE-ACC8-6BA6D4207C09}"
 	ProjectSection(SolutionItems) = preProject
@@ -30,9 +30,6 @@ EndProject
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "SampleApp", "samples\SampleApp\SampleApp.csproj", "{AF5BB04E-92F7-4737-8B98-F86F6244FAB2}"
 EndProject
 Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "test", "test", "{9E49B5B9-9E72-42FB-B684-90CA1B1BCF9C}"
-	ProjectSection(SolutionItems) = preProject
-		test\Directory.Build.props = test\Directory.Build.props
-	EndProjectSection
 EndProject
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "Microsoft.AspNetCore.FunctionalTests", "test\Microsoft.AspNetCore.FunctionalTests\Microsoft.AspNetCore.FunctionalTests.csproj", "{C72A756A-D29D-44C7-83D4-821DBE82DBCA}"
 EndProject
@@ -52,6 +49,8 @@ Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "DependencyInjectionApp", "t
 EndProject
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "CreateDefaultBuilderOfTApp", "test\TestSites\CreateDefaultBuilderOfTApp\CreateDefaultBuilderOfTApp.csproj", "{A922B5AC-836B-44F4-83F1-3CB9EB08A3F8}"
 EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Microsoft.AspNetCore.Tests", "test\Microsoft.AspNetCore.Tests\Microsoft.AspNetCore.Tests.csproj", "{BD08F027-3BB9-427B-9367-19534B7376B3}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -102,6 +101,10 @@ Global
 		{A922B5AC-836B-44F4-83F1-3CB9EB08A3F8}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{A922B5AC-836B-44F4-83F1-3CB9EB08A3F8}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{A922B5AC-836B-44F4-83F1-3CB9EB08A3F8}.Release|Any CPU.Build.0 = Release|Any CPU
+		{BD08F027-3BB9-427B-9367-19534B7376B3}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{BD08F027-3BB9-427B-9367-19534B7376B3}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{BD08F027-3BB9-427B-9367-19534B7376B3}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{BD08F027-3BB9-427B-9367-19534B7376B3}.Release|Any CPU.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE
@@ -120,6 +123,7 @@ Global
 		{67E4C92F-6D12-4C52-BB79-B8D11BFC6B82} = {ED834E68-51C3-4ADE-ACC8-6BA6D4207C09}
 		{65FE2E38-4529-4C93-A7B0-CF12DD7A70C3} = {EC22261D-0DE1-47DE-8F7C-072675D6F5B4}
 		{A922B5AC-836B-44F4-83F1-3CB9EB08A3F8} = {EC22261D-0DE1-47DE-8F7C-072675D6F5B4}
+		{BD08F027-3BB9-427B-9367-19534B7376B3} = {9E49B5B9-9E72-42FB-B684-90CA1B1BCF9C}
 	EndGlobalSection
 	GlobalSection(ExtensibilityGlobals) = postSolution
 		SolutionGuid = {A666E9B0-125B-4975-B35B-09A6D68A5047}

samples/SampleApp/Program.cs

@@ -2,7 +2,6 @@
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
 using System;
-using System.Threading.Tasks;
 using Microsoft.AspNetCore;
 using Microsoft.AspNetCore.Builder;
 using Microsoft.AspNetCore.Hosting;

src/Microsoft.AspNetCore/WebHost.cs

@@ -185,6 +185,11 @@ namespace Microsoft.AspNetCore
                     options.ValidateScopes = context.HostingEnvironment.IsDevelopment();
                 });
 
+            if (args != null)
+            {
+                builder.UseConfiguration(new ConfigurationBuilder().AddCommandLine(args).Build());
+            }
+
             return builder;
         }
 
@@ -206,10 +211,7 @@ namespace Microsoft.AspNetCore
         /// <typeparam name ="TStartup">The type containing the startup methods for the application.</typeparam>
         /// <param name="args">The command line args.</param>
         /// <returns>The initialized <see cref="IWebHostBuilder"/>.</returns>
-        public static IWebHostBuilder CreateDefaultBuilder<TStartup>(string[] args) where TStartup : class
+        public static IWebHostBuilder CreateDefaultBuilder<TStartup>(string[] args) where TStartup : class =>
-        {
+            CreateDefaultBuilder(args).UseStartup<TStartup>();
-            return CreateDefaultBuilder(args)
-                .UseStartup<TStartup>();
-        }
     }
 }

test/Microsoft.AspNetCore.Tests/Microsoft.AspNetCore.Tests.csproj

@@ -0,0 +1,16 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <TargetFrameworks>netcoreapp2.0;net461</TargetFrameworks>
+    <TargetFrameworks Condition=" '$(OS)' != 'Windows_NT' ">netcoreapp2.0</TargetFrameworks>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="..\..\src\Microsoft.AspNetCore\Microsoft.AspNetCore.csproj" />
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="$(TestSdkVersion)" />
+    <PackageReference Include="Moq" Version="$(MoqVersion)" />
+    <PackageReference Include="xunit.runner.visualstudio" Version="$(XunitVersion)" />
+    <PackageReference Include="xunit" Version="$(XunitVersion)" />
+  </ItemGroup>
+
+</Project>

test/Microsoft.AspNetCore.Tests/WebHostTests.cs

@@ -0,0 +1,18 @@
+// 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 Microsoft.AspNetCore.Hosting;
+using Xunit;
+
+namespace Microsoft.AspNetCore.Tests
+{
+    public class WebHostTests
+    {
+        [Fact]
+        public void WebHostConfiguration_IncludesCommandLineArguments()
+        {
+            var builder = WebHost.CreateDefaultBuilder(new string[] { "--urls", "http://localhost:5001" });
+            Assert.Equal("http://localhost:5001", builder.GetSetting(WebHostDefaults.ServerUrlsKey));
+        }
+    }
+}