Move Go to definition to new fully loaded document API.

src/EditorFeatures/Core/GoToDefinition/GoToDefinitionCommandHandler.cs

@@ -10,6 +10,7 @@
 using Microsoft.VisualStudio.Text;
 using Microsoft.VisualStudio.Text.Editor.Commanding.Commands;
 using Microsoft.VisualStudio.Utilities;
+using Roslyn.Utilities;
 using VSCommanding = Microsoft.VisualStudio.Commanding;
 
 namespace Microsoft.CodeAnalysis.Editor.GoToDefinition
@@ -30,7 +31,8 @@ internal class GoToDefinitionCommandHandler :
 
         public VSCommanding.CommandState GetCommandState(GoToDefinitionCommandArgs args)
         {
-            var (document, service) = GetDocumentAndService(args.SubjectBuffer.CurrentSnapshot);
+            var document = args.SubjectBuffer.CurrentSnapshot.GetOpenDocumentInCurrentContextWithChanges();
+            var service = document?.GetLanguageService<IGoToDefinitionService>();
             return service != null
                 ? VSCommanding.CommandState.Available
                 : VSCommanding.CommandState.Unavailable;
@@ -38,18 +40,23 @@ public VSCommanding.CommandState GetCommandState(GoToDefinitionCommandArgs args)
 
         public bool ExecuteCommand(GoToDefinitionCommandArgs args, CommandExecutionContext context)
         {
-            var subjectBuffer = args.SubjectBuffer;
-            var (document, service) = GetDocumentAndService(subjectBuffer.CurrentSnapshot);
-            if (service != null)
+            using (context.OperationContext.AddScope(allowCancellation: true, EditorFeaturesResources.Navigating_to_definition))
             {
-                var caretPos = args.TextView.GetCaretPoint(subjectBuffer);
-                if (caretPos.HasValue && TryExecuteCommand(document, caretPos.Value, service, context))
+                var subjectBuffer = args.SubjectBuffer;
+                var document = subjectBuffer.CurrentSnapshot.GetFullyLoadedOpenDocumentInCurrentContextWithChangesAsync(
+                    context.OperationContext).WaitAndGetResult(context.OperationContext.UserCancellationToken);
+                var service = document?.GetLanguageService<IGoToDefinitionService>();
+                if (service != null)
                 {
-                    return true;
+                    var caretPos = args.TextView.GetCaretPoint(subjectBuffer);
+                    if (caretPos.HasValue && TryExecuteCommand(document, caretPos.Value, service, context))
+                    {
+                        return true;
+                    }
                 }
-            }
 
-            return false;
+                return false;
+            }
         }
 
         // Internal for testing purposes only.
@@ -61,30 +68,20 @@ internal bool TryExecuteCommand(Document document, int caretPosition, CommandExe
 
         internal bool TryExecuteCommand(Document document, int caretPosition, IGoToDefinitionService goToDefinitionService, CommandExecutionContext context)
         {
-            string errorMessage = null;
-
-            using (context.OperationContext.AddScope(allowCancellation: true, EditorFeaturesResources.Navigating_to_definition))
-            {
-                if (goToDefinitionService != null &&
-                    goToDefinitionService.TryGoToDefinition(document, caretPosition, context.OperationContext.UserCancellationToken))
-                {
-                    return true;
-                }
-
-                errorMessage = EditorFeaturesResources.Cannot_navigate_to_the_symbol_under_the_caret;
-            }
-
-            if (errorMessage != null)
+            if (goToDefinitionService != null &&
+                goToDefinitionService.TryGoToDefinition(document, caretPosition, context.OperationContext.UserCancellationToken))
             {
-                // We are about to show a modal UI dialog so we should take over the command execution
-                // wait context. That means the command system won't attempt to show its own wait dialog 
-                // and also will take it into consideration when measuring command handling duration.
-                context.OperationContext.TakeOwnership();
-                var workspace = document.Project.Solution.Workspace;
-                var notificationService = workspace.Services.GetService<INotificationService>();
-                notificationService.SendNotification(errorMessage, title: EditorFeaturesResources.Go_to_Definition, severity: NotificationSeverity.Information);
+                return true;
             }
 
+            var errorMessage = EditorFeaturesResources.Cannot_navigate_to_the_symbol_under_the_caret;
+            // We are about to show a modal UI dialog so we should take over the command execution
+            // wait context. That means the command system won't attempt to show its own wait dialog 
+            // and also will take it into consideration when measuring command handling duration.
+            context.OperationContext.TakeOwnership();
+            var workspace = document.Project.Solution.Workspace;
+            var notificationService = workspace.Services.GetService<INotificationService>();
+            notificationService.SendNotification(errorMessage, title: EditorFeaturesResources.Go_to_Definition, severity: NotificationSeverity.Information);
             return true;
         }
     }