Tweak roslyn helpers and nullability

Author: davidwengier

src/Razor/src/Microsoft.AspNetCore.Razor.LanguageServer/CodeActions/RoslynCodeActionHelpers.cs

@@ -5,19 +5,24 @@
 using System.Threading;
 using System.Threading.Tasks;
 using Microsoft.AspNetCore.Razor.LanguageServer.Hosting;
+using Microsoft.CodeAnalysis.CSharp;
+using Microsoft.CodeAnalysis;
 using Microsoft.CodeAnalysis.Razor.CodeActions;
 using Microsoft.CodeAnalysis.Razor.ProjectSystem;
 using Microsoft.CodeAnalysis.Razor.Protocol;
 using Microsoft.CodeAnalysis.Razor.Protocol.CodeActions;
 using Microsoft.VisualStudio.LanguageServer.Protocol;
+using Microsoft.CodeAnalysis.Formatting;
 
 namespace Microsoft.AspNetCore.Razor.LanguageServer.CodeActions;
 
 internal sealed class RoslynCodeActionHelpers(IClientConnection clientConnection) : IRoslynCodeActionHelpers
 {
+    private static readonly Lazy<Workspace> s_workspace = new Lazy<Workspace>(() => new AdhocWorkspace());
+
     private readonly IClientConnection _clientConnection = clientConnection;
 
-    public Task<string?> GetFormattedNewFileContentsAsync(IProjectSnapshot projectSnapshot, Uri csharpFileUri, string newFileContent, CancellationToken cancellationToken)
+    public async Task<string> GetFormattedNewFileContentsAsync(IProjectSnapshot projectSnapshot, Uri csharpFileUri, string newFileContent, CancellationToken cancellationToken)
     {
         var parameters = new FormatNewFileParams()
         {
@@ -31,7 +36,20 @@ internal sealed class RoslynCodeActionHelpers(IClientConnection clientConnection
             },
             Contents = newFileContent
         };
-        return _clientConnection.SendRequestAsync<FormatNewFileParams, string?>(CustomMessageNames.RazorFormatNewFileEndpointName, parameters, cancellationToken);
+
+        var fixedContent = await _clientConnection.SendRequestAsync<FormatNewFileParams, string?>(CustomMessageNames.RazorFormatNewFileEndpointName, parameters, cancellationToken).ConfigureAwait(false);
+
+        if (fixedContent is not null)
+        {
+            return fixedContent;
+        }
+
+        // Sadly we can't use a "real" workspace here, because we don't have access. If we use our workspace, it wouldn't have the right settings
+        // for C# formatting, only Razor formatting, and we have no access to Roslyn's real workspace, since it could be in another process.
+        var node = await CSharpSyntaxTree.ParseText(newFileContent, cancellationToken: cancellationToken).GetRootAsync(cancellationToken).ConfigureAwait(false);
+        node = Formatter.Format(node, s_workspace.Value, cancellationToken: cancellationToken);
+
+        return node.ToFullString();
     }
 
     public Task<TextEdit[]?> GetSimplifiedTextEditsAsync(DocumentContext documentContext, Uri? codeBehindUri, TextEdit edit, CancellationToken cancellationToken)

src/Razor/src/Microsoft.CodeAnalysis.Razor.Workspaces/CodeActions/Razor/ExtractToCodeBehindCodeActionResolver.cs

@@ -10,8 +10,6 @@
 using Microsoft.AspNetCore.Razor.Language.Intermediate;
 using Microsoft.AspNetCore.Razor.PooledObjects;
 using Microsoft.AspNetCore.Razor.Utilities;
-using Microsoft.CodeAnalysis.CSharp;
-using Microsoft.CodeAnalysis.Formatting;
 using Microsoft.CodeAnalysis.Razor.CodeActions.Models;
 using Microsoft.CodeAnalysis.Razor.Formatting;
 using Microsoft.CodeAnalysis.Razor.ProjectSystem;
@@ -26,8 +24,6 @@ internal class ExtractToCodeBehindCodeActionResolver(
     LanguageServerFeatureOptions languageServerFeatureOptions,
     IRoslynCodeActionHelpers roslynCodeActionHelpers) : IRazorCodeActionResolver
 {
-    private static readonly Workspace s_workspace = new AdhocWorkspace();
-
     private readonly LanguageServerFeatureOptions _languageServerFeatureOptions = languageServerFeatureOptions;
     private readonly IRoslynCodeActionHelpers _roslynCodeActionHelpers = roslynCodeActionHelpers;
 
@@ -134,18 +130,6 @@ private async Task<string> GenerateCodeBehindClassAsync(IProjectSnapshot project
 
         var newFileContent = builder.ToString();
 
-        var fixedContent = await _roslynCodeActionHelpers.GetFormattedNewFileContentsAsync(project, codeBehindUri, newFileContent, cancellationToken).ConfigureAwait(false);
-
-        if (fixedContent is null)
-        {
-            // Sadly we can't use a "real" workspace here, because we don't have access. If we use our workspace, it wouldn't have the right settings
-            // for C# formatting, only Razor formatting, and we have no access to Roslyn's real workspace, since it could be in another process.
-            var node = await CSharpSyntaxTree.ParseText(newFileContent, cancellationToken: cancellationToken).GetRootAsync(cancellationToken).ConfigureAwait(false);
-            node = Formatter.Format(node, s_workspace, cancellationToken: cancellationToken);
-
-            return node.ToFullString();
-        }
-
-        return fixedContent;
+        return await _roslynCodeActionHelpers.GetFormattedNewFileContentsAsync(project, codeBehindUri, newFileContent, cancellationToken).ConfigureAwait(false);
     }
 }

src/Razor/src/Microsoft.CodeAnalysis.Razor.Workspaces/CodeActions/Razor/IRoslynCodeActionHelpers.cs

@@ -11,7 +11,7 @@ namespace Microsoft.CodeAnalysis.Razor.CodeActions;
 
 internal interface IRoslynCodeActionHelpers
 {
-    Task<string?> GetFormattedNewFileContentsAsync(IProjectSnapshot projectSnapshot, Uri csharpFileUri, string newFileContent, CancellationToken cancellationToken);
+    Task<string> GetFormattedNewFileContentsAsync(IProjectSnapshot projectSnapshot, Uri csharpFileUri, string newFileContent, CancellationToken cancellationToken);
 
     /// <summary>
     /// Apply the edit to the specified document, get Roslyn to simplify it, and return the simplified edit

src/Razor/src/Microsoft.CodeAnalysis.Remote.Razor/CodeActions/RoslynCodeActionHelpers.cs

@@ -22,14 +22,14 @@ namespace Microsoft.CodeAnalysis.Remote.Razor;
 [Export(typeof(IRoslynCodeActionHelpers)), Shared]
 internal sealed class RoslynCodeActionHelpers : IRoslynCodeActionHelpers
 {
-    public Task<string?> GetFormattedNewFileContentsAsync(IProjectSnapshot projectSnapshot, Uri csharpFileUri, string newFileContent, CancellationToken cancellationToken)
+    public Task<string> GetFormattedNewFileContentsAsync(IProjectSnapshot projectSnapshot, Uri csharpFileUri, string newFileContent, CancellationToken cancellationToken)
     {
         Debug.Assert(projectSnapshot is RemoteProjectSnapshot);
         var project = ((RemoteProjectSnapshot)projectSnapshot).Project;
 
         var document = project.AddDocument(RazorUri.GetDocumentFilePathFromUri(csharpFileUri), newFileContent);
 
-        return ExternalHandlers.CodeActions.GetFormattedNewFileContentAsync(document, cancellationToken)!;
+        return ExternalHandlers.CodeActions.GetFormattedNewFileContentAsync(document, cancellationToken);
     }
 
     public async Task<TextEdit[]?> GetSimplifiedTextEditsAsync(DocumentContext documentContext, Uri? codeBehindUri, TextEdit edit, CancellationToken cancellationToken)