Need apphost in build but do not pack it

Author: William Li

src/Tasks/Microsoft.NET.Build.Tasks/ResolveToolPackagePaths.cs

@@ -1,6 +1,7 @@
 // Copyright (c) .NET Foundation and contributors. All rights reserved.
 // Licensed under the MIT license. See LICENSE file in the project root for full license information.
 
+using System;
 using System.Collections.Generic;
 using System.IO;
 using System.Linq;
@@ -16,6 +17,8 @@ namespace Microsoft.NET.Build.Tasks
     /// </summary>
     public sealed class ResolveToolPackagePaths : TaskBase
     {
+        public string AppHostIntermediatePath { get; set; }
+
         [Required]
         public ITaskItem[] ResolvedFileToPublish { get; set; }
 
@@ -36,6 +39,12 @@ protected override void ExecuteCore()
             var result = new List<TaskItem>();
             foreach (ITaskItem r in ResolvedFileToPublish)
             {
+                // skip packing apphost since a dotnet tool will get a generated shim executable once installed
+                if (r.ItemSpec.Equals(AppHostIntermediatePath, StringComparison.Ordinal))
+                {
+                    continue;
+                }
+
                 string relativePath = r.GetMetadata("RelativePath");
                 var fullpath = Path.GetFullPath(
                     Path.Combine(PublishDir,

src/Tasks/Microsoft.NET.Build.Tasks/targets/Microsoft.NET.PackTool.targets

@@ -37,6 +37,7 @@ Copyright (c) .NET Foundation. All rights reserved.
     </ItemGroup>
 
     <ResolveToolPackagePaths
+      AppHostIntermediatePath="$(AppHostIntermediatePath)"
       ResolvedFileToPublish="@(ResolvedFileToPublish)"
       PublishDir="$(PublishDir)"
       TargetFramework="$(TargetFramework)">

src/Tasks/Microsoft.NET.Build.Tasks/targets/Microsoft.NET.RuntimeIdentifierInference.targets

@@ -104,7 +104,6 @@ Copyright (c) .NET Foundation. All rights reserved.
     <SelfContained Condition="'$(SelfContained)' == '' and '$(RuntimeIdentifier)' != ''">true</SelfContained>
     <SelfContained Condition="'$(SelfContained)' == ''">false</SelfContained>
     <UseAppHost Condition="'$(UseAppHost)' == '' and
-                           ('$(SelfContained)' == 'true' or '$(PackAsTool)' != 'true') and
                            ('$(SelfContained)' == 'true' or
                             ('$(RuntimeIdentifier)' != '' and '$(_TargetFrameworkVersionWithoutV)' >= '2.1') or
                             '$(_TargetFrameworkVersionWithoutV)' >= '3.0')">true</UseAppHost>

src/Tests/Microsoft.NET.ToolPack.Tests/GivenThatWeWantToPackAToolProject.cs

@@ -15,6 +15,7 @@
 using System.Runtime.CompilerServices;
 using System;
 using System.Runtime.InteropServices;
+using Microsoft.DotNet.PlatformAbstractions;
 
 namespace Microsoft.NET.ToolPack.Tests
 {
@@ -125,10 +126,10 @@ public void It_contains_runtimeconfig_for_each_tfm(bool multiTarget)
             }
         }
 
-        [Theory]
+        [WindowsOnlyTheory]
         [InlineData(true)]
         [InlineData(false)]
-        public void It_does_not_contain_apphost_exe(bool multiTarget)
+        public void Given_Windows_It_does_not_contain_apphost_exe_but_RunCommand_is_apphost_exe(bool multiTarget)
         {
             _targetFrameworkOrFrameworks = "netcoreapp3.0";
 
@@ -140,7 +141,7 @@ public void It_does_not_contain_apphost_exe(bool multiTarget)
 
                 foreach (NuGet.Frameworks.NuGetFramework framework in supportedFrameworks)
                 {
-                    var extension = RuntimeInformation.IsOSPlatform(OSPlatform.Windows) ? ".exe" : "";
+                    var extension =".exe";
                     var allItems = nupkgReader.GetToolItems().SelectMany(i => i.Items).ToList();
                     allItems.Should().NotContain($"tools/{framework.GetShortFolderName()}/any/consoledemo{extension}");
                 }
@@ -154,8 +155,45 @@ public void It_does_not_contain_apphost_exe(bool multiTarget)
                GetValuesCommand.ValueType.Property);
 
             getValuesCommand.Execute();
-            Path.GetExtension(getValuesCommand.GetValues().Single())
-                .Should().NotBe(".exe", "Repro https://github.com/dotnet/cli/issues/11299");
+            string runCommandPath = getValuesCommand.GetValues().Single();
+            Path.GetExtension(runCommandPath)
+                .Should().Be(".exe");
+            File.Exists(runCommandPath).Should()
+                .BeTrue("run command should be apphost exe for WinExe to debug. But it will not be packed");
+        }
+
+        [PlatformSpecificTheory(Platform.Linux, Platform.Darwin, Platform.FreeBSD)]
+        [InlineData(true)]
+        [InlineData(false)]
+        public void Given_nonwindows_It_does_not_contain_apphost_and_RunCommand_is_not_apphost(bool multiTarget)
+        {
+            _targetFrameworkOrFrameworks = "netcoreapp3.0";
+
+            var nugetPackage = SetupNuGetPackage(multiTarget);
+            using (var nupkgReader = new PackageArchiveReader(nugetPackage))
+            {
+                IEnumerable<NuGet.Frameworks.NuGetFramework> supportedFrameworks = nupkgReader.GetSupportedFrameworks();
+                supportedFrameworks.Should().NotBeEmpty();
+
+                foreach (NuGet.Frameworks.NuGetFramework framework in supportedFrameworks)
+                {
+                    var allItems = nupkgReader.GetToolItems().SelectMany(i => i.Items).ToList();
+                    allItems.Should().NotContain($"tools/{framework.GetShortFolderName()}/any/consoledemo");
+                }
+            }
+
+            var getValuesCommand = new GetValuesCommand(
+               Log,
+               _testRoot,
+               _targetFrameworkOrFrameworks,
+               "RunCommand",
+               GetValuesCommand.ValueType.Property);
+
+            getValuesCommand.Execute();
+            string runCommandPath = getValuesCommand.GetValues().Single();
+            Path.GetExtension(runCommandPath)
+                .Should().NotBe(".exe");
+            File.Exists(runCommandPath).Should().BeTrue("non Windows does not generate apphost by default");
         }
 
         [Theory]