Let SDK provide the API to avoid a circular dependency

Author: jjonescz

src/NuGet.Core/NuGet.CommandLine.XPlat/NuGet.CommandLine.XPlat.csproj

@@ -17,7 +17,6 @@
   </ItemGroup>
 
   <ItemGroup>
-    <PackageReference Include="Microsoft.DotNet.ProjectTools" />
     <PackageReference Include="Microsoft.Extensions.CommandLineUtils.Sources" PrivateAssets="All" />
     <PackageReference Include="Microsoft.Build" ExcludeAssets="runtime" />
     <PackageReference Include="Spectre.Console" />

src/NuGet.Core/NuGet.CommandLine.XPlat/NuGetCommands.cs

@@ -6,6 +6,8 @@
 using System;
 using System.CommandLine;
 using System.Linq;
+using Microsoft.Build.Construction;
+using Microsoft.Build.Evaluation;
 using NuGet.CommandLine.XPlat.Commands.Package.PackageDownload;
 using NuGet.CommandLine.XPlat.Commands.Package.Update;
 
@@ -16,6 +18,8 @@ namespace NuGet.CommandLine.XPlat;
 /// </summary>
 public static class NuGetCommands
 {
+    public static IVirtualProjectBuilder? VirtualProjectBuilder { get; set; }
+
     /// <summary>
     /// <para>Adds NuGet's dotnet CLI commands to the dotnet CLI RootCommand object</para>
     /// </summary>
@@ -47,3 +51,10 @@ public static void Add(RootCommand rootCommand)
         Add(rootCommand, interactiveOption);
     }
 }
+
+public interface IVirtualProjectBuilder
+{
+    bool IsValidEntryPointPath(string entryPointFilePath);
+
+    ProjectRootElement CreateProjectRootElement(string entryPointFilePath, ProjectCollection projectCollection);
+}

src/NuGet.Core/NuGet.CommandLine.XPlat/PublicAPI.Unshipped.txt

@@ -1 +1,6 @@
 #nullable enable
+NuGet.CommandLine.XPlat.IVirtualProjectBuilder
+NuGet.CommandLine.XPlat.IVirtualProjectBuilder.CreateProjectRootElement(string! entryPointFilePath, Microsoft.Build.Evaluation.ProjectCollection! projectCollection) -> Microsoft.Build.Construction.ProjectRootElement!
+NuGet.CommandLine.XPlat.IVirtualProjectBuilder.IsValidEntryPointPath(string! entryPointFilePath) -> bool
+static NuGet.CommandLine.XPlat.NuGetCommands.VirtualProjectBuilder.get -> NuGet.CommandLine.XPlat.IVirtualProjectBuilder?
+static NuGet.CommandLine.XPlat.NuGetCommands.VirtualProjectBuilder.set -> void

src/NuGet.Core/NuGet.CommandLine.XPlat/Utility/MSBuildAPIUtility.cs

@@ -14,7 +14,6 @@
 using Microsoft.Build.Construction;
 using Microsoft.Build.Evaluation;
 using Microsoft.Build.Execution;
-using Microsoft.DotNet.ProjectTools;
 using NuGet.Common;
 using NuGet.Frameworks;
 using NuGet.LibraryModel;
@@ -1040,13 +1039,10 @@ private static IEnumerable<string> GetProjectFrameworks(Project project)
 
         private static ProjectRootElement TryOpenProjectRootElement(string filename)
         {
-            if (VirtualProjectBuilder.IsValidEntryPointPath(filename))
+            var virtualProjectBuilder = NuGetCommands.VirtualProjectBuilder;
+            if (virtualProjectBuilder != null && virtualProjectBuilder.IsValidEntryPointPath(filename))
             {
-                // TODO: Don't hardcode TFM.
-                return VirtualProjectBuilder.CreateProjectRootElement(
-                    filePath: filename,
-                    targetFrameworkVersion: "10.0",
-                    ProjectCollection.GlobalProjectCollection);
+                return virtualProjectBuilder.CreateProjectRootElement(filename, ProjectCollection.GlobalProjectCollection);
             }
 
             try