Allow Razor to get task list items for a document (#80102)

Missed this when doing diagnostics

Author: davidwengier

src/LanguageServer/Protocol/Handler/Diagnostics/DiagnosticSources/TaskListDiagnosticSource.cs

@@ -29,17 +29,19 @@ internal sealed class TaskListDiagnosticSource(Document document, IGlobalOptionS
 
     private readonly IGlobalOptionService _globalOptions = globalOptions;
 
-    public override async Task<ImmutableArray<DiagnosticData>> GetDiagnosticsAsync(
-        RequestContext context, CancellationToken cancellationToken)
+    public override Task<ImmutableArray<DiagnosticData>> GetDiagnosticsAsync(RequestContext context, CancellationToken cancellationToken)
+        => GetTaskListItemsAsync(this.Document, _globalOptions, cancellationToken);
+
+    internal static async Task<ImmutableArray<DiagnosticData>> GetTaskListItemsAsync(Document document, IGlobalOptionService globalOptions, CancellationToken cancellationToken)
     {
-        var service = this.Document.GetLanguageService<ITaskListService>();
+        var service = document.GetLanguageService<ITaskListService>();
         if (service == null)
             return [];
 
-        var options = _globalOptions.GetTaskListOptions();
+        var options = globalOptions.GetTaskListOptions();
         var descriptors = GetAndCacheDescriptors(options.Descriptors);
 
-        var items = await service.GetTaskListItemsAsync(this.Document, descriptors, cancellationToken).ConfigureAwait(false);
+        var items = await service.GetTaskListItemsAsync(document, descriptors, cancellationToken).ConfigureAwait(false);
         if (items.Length == 0)
             return [];
 
@@ -53,9 +55,9 @@ public override async Task<ImmutableArray<DiagnosticData>> GetDiagnosticsAsync(
             warningLevel: 0,
             customTags: s_todoCommentCustomTags,
             properties: GetProperties(i.Priority),
-            projectId: this.Document.Project.Id,
-            language: this.Document.Project.Language,
-            location: new DiagnosticDataLocation(i.Span, this.Document.Id, mappedFileSpan: i.MappedSpan)));
+            projectId: document.Project.Id,
+            language: document.Project.Language,
+            location: new DiagnosticDataLocation(i.Span, document.Id, mappedFileSpan: i.MappedSpan)));
     }
 
     private static ImmutableDictionary<string, string?> GetProperties(TaskListItemPriority priority)

src/Tools/ExternalAccess/Razor/Features/Cohost/Handlers/Diagnostics.cs

@@ -7,6 +7,7 @@
 using System.Threading.Tasks;
 using Microsoft.CodeAnalysis.Diagnostics;
 using Microsoft.CodeAnalysis.LanguageServer;
+using Microsoft.CodeAnalysis.LanguageServer.Handler.Diagnostics;
 using Microsoft.CodeAnalysis.Options;
 using Microsoft.CodeAnalysis.PooledObjects;
 using LSP = Roslyn.LanguageServer.Protocol;
@@ -24,6 +25,21 @@ internal static class Diagnostics
         var diagnostics = await diagnosticAnalyzerService.GetDiagnosticsForSpanAsync(
             document, range: null, DiagnosticKind.All, cancellationToken).ConfigureAwait(false);
 
+        return GetLspDiagnostics(document, supportsVisualStudioExtensions, globalOptionsService, diagnostics);
+    }
+
+    public static async Task<ImmutableArray<LSP.Diagnostic>> GetTaskListAsync(Document document, bool supportsVisualStudioExtensions, CancellationToken cancellationToken)
+    {
+        var solutionServices = document.Project.Solution.Services;
+        var globalOptionsService = solutionServices.ExportProvider.GetService<IGlobalOptionService>();
+
+        var items = await TaskListDiagnosticSource.GetTaskListItemsAsync(document, globalOptionsService, cancellationToken).ConfigureAwait(false);
+
+        return GetLspDiagnostics(document, supportsVisualStudioExtensions, globalOptionsService, items);
+    }
+
+    private static ImmutableArray<LSP.Diagnostic> GetLspDiagnostics(Document document, bool supportsVisualStudioExtensions, IGlobalOptionService globalOptionsService, ImmutableArray<DiagnosticData> diagnostics)
+    {
         var project = document.Project;
         // Potential duplicate is only set for workspace diagnostics
         const bool PotentialDuplicate = false;