Fix versioned sdk imports in file-based programs (#49008)

Author: RikkiGibson

src/Cli/dotnet/Commands/Run/VirtualProjectBuildingCommand.cs

@@ -510,9 +510,7 @@ public static void WriteProjectFile(
         {
             if (isVirtualProject)
             {
-                writer.WriteLine($"""
-                      <Import Project="Sdk.props" Sdk="{EscapeValue(sdk.ToSlashDelimitedString())}" />
-                    """);
+                WriteImport(writer, "Sdk.props", sdk);
             }
             else if (sdk.Version is null)
             {
@@ -629,9 +627,7 @@ public static void WriteProjectFile(
 
             foreach (var sdk in sdkDirectives)
             {
-                writer.WriteLine($"""
-                      <Import Project="Sdk.targets" Sdk="{EscapeValue(sdk.ToSlashDelimitedString())}" />
-                    """);
+                WriteImport(writer, "Sdk.targets", sdk);
             }
 
             if (!sdkDirectives.Any())
@@ -679,6 +675,22 @@ Override targets which don't work with project files that are not present on dis
             """);
 
         static string EscapeValue(string value) => SecurityElement.Escape(value);
+
+        static void WriteImport(TextWriter writer, string project, CSharpDirective.Sdk sdk)
+        {
+            if (sdk.Version is null)
+            {
+                writer.WriteLine($"""
+                      <Import Project="{EscapeValue(project)}" Sdk="{EscapeValue(sdk.Name)}" />
+                    """);
+            }
+            else
+            {
+                writer.WriteLine($"""
+                      <Import Project="{EscapeValue(project)}" Sdk="{EscapeValue(sdk.Name)}" Version="{EscapeValue(sdk.Version)}" />
+                    """);
+            }
+        }
     }
 
     /// <param name="reportAllErrors">

test/dotnet.Tests/CommandTests/Run/RunFileTests.cs

@@ -973,6 +973,25 @@ public void PackageReference_CentralVersion()
                 """);
     }
 
+    [Fact] // https://github.com/dotnet/sdk/issues/48990
+    public void SdkReference()
+    {
+        var testInstance = _testAssetsManager.CreateTestDirectory();
+        File.WriteAllText(Path.Join(testInstance.Path, "Program.cs"), """
+            #:sdk Microsoft.NET.Sdk
+            #:sdk Aspire.AppHost.Sdk 9.2.1
+            #:package [email protected]
+
+            var builder = DistributedApplication.CreateBuilder(args);
+            builder.Build().Run();
+            """);
+
+        new DotnetCommand(Log, "build", "Program.cs")
+            .WithWorkingDirectory(testInstance.Path)
+            .Execute()
+            .Should().Pass();
+    }
+
     [Fact]
     public void UpToDate()
     {
@@ -1176,7 +1195,7 @@ public void Api()
 
                       <!-- We need to explicitly import Sdk props/targets so we can override the targets below. -->
                       <Import Project="Sdk.props" Sdk="Microsoft.NET.Sdk" />
-                      <Import Project="Sdk.props" Sdk="Aspire.Hosting.Sdk/9.1.0" />
+                      <Import Project="Sdk.props" Sdk="Aspire.Hosting.Sdk" Version="9.1.0" />
 
                       <PropertyGroup>
                         <OutputType>Exe</OutputType>
@@ -1207,7 +1226,7 @@ public void Api()
                       </ItemGroup>
 
                       <Import Project="Sdk.targets" Sdk="Microsoft.NET.Sdk" />
-                      <Import Project="Sdk.targets" Sdk="Aspire.Hosting.Sdk/9.1.0" />
+                      <Import Project="Sdk.targets" Sdk="Aspire.Hosting.Sdk" Version="9.1.0" />
 
                       <!--
                         Override targets which don't work with project files that are not present on disk.