Merge pull request #2996 from DustinCampbell/fix-2893

Ensure that calls into EnvDTE.CodeModel work even if the underlying FileCodeModel has not been realized

src/VisualStudio/Core/Impl/CodeModel/AbstractProjectCodeModel.cs

@@ -58,14 +58,25 @@ internal CodeModelProjectCache GetCodeModelCache()
             }
         }
 
-        public IEnumerable<ComHandle<EnvDTE80.FileCodeModel2, FileCodeModel>> GetFileCodeModelInstances()
+        public IEnumerable<ComHandle<EnvDTE80.FileCodeModel2, FileCodeModel>> GetCachedFileCodeModelInstances()
         {
             return GetCodeModelCache().GetFileCodeModelInstances();
         }
 
-        public ComHandle<EnvDTE80.FileCodeModel2, FileCodeModel>? GetFileCodeModelInstance(string fileName)
+        public bool TryGetCachedFileCodeModel(string fileName, out ComHandle<EnvDTE80.FileCodeModel2, FileCodeModel> fileCodeModelHandle)
         {
-            return GetCodeModelCache().GetComHandleForFileCodeModel(fileName);
+            var handle = GetCodeModelCache().GetComHandleForFileCodeModel(fileName);
+
+            fileCodeModelHandle = handle != null
+                ? handle.Value
+                : default(ComHandle<EnvDTE80.FileCodeModel2, FileCodeModel>);
+
+            return handle != null;
+        }
+
+        public ComHandle<EnvDTE80.FileCodeModel2, FileCodeModel> GetOrCreateFileCodeModel(string fileName)
+        {
+            return GetCodeModelCache().GetOrCreateFileCodeModel(fileName);
         }
 
         internal abstract bool CanCreateFileCodeModelThroughProject(string fileName);

src/VisualStudio/Core/Impl/CodeModel/CodeModelIncrementalAnalyzer.cs

@@ -10,6 +10,7 @@
 using Microsoft.CodeAnalysis.Options;
 using Microsoft.CodeAnalysis.Shared.TestHooks;
 using Microsoft.CodeAnalysis.SolutionCrawler;
+using Microsoft.VisualStudio.LanguageServices.Implementation.Interop;
 using Microsoft.VisualStudio.LanguageServices.Implementation.ProjectSystem;
 using Roslyn.Utilities;
 
@@ -87,13 +88,13 @@ public void FireEvents(DocumentId documentId, CancellationToken cancellationToke
                     return;
                 }
 
-                var fileCodeModel = codeModelProvider.ProjectCodeModel.GetFileCodeModelInstance(filename);
-                if (fileCodeModel == null)
+                ComHandle<EnvDTE80.FileCodeModel2, FileCodeModel> fileCodeModelHandle;
+                if (!codeModelProvider.ProjectCodeModel.TryGetCachedFileCodeModel(filename, out fileCodeModelHandle))
                 {
                     return;
                 }
 
-                var codeModel = fileCodeModel.Value.Object;
+                var codeModel = fileCodeModelHandle.Object;
                 _notificationService.RegisterNotification(() => codeModel.FireEvents(), _listener.BeginAsyncOperation("CodeModelEvent"), cancellationToken);
             }
 

src/VisualStudio/Core/Impl/CodeModel/FileCodeModel_Events.cs

@@ -63,8 +63,8 @@ public bool FireEvents()
                 return needMoreTime;
             }
 
-            var comHandleToThis = provider.ProjectCodeModel.GetFileCodeModelInstance(this.Workspace.GetFilePath(GetDocumentId()));
-            if (comHandleToThis == null)
+            ComHandle<EnvDTE80.FileCodeModel2, FileCodeModel> fileCodeModelHandle;
+            if (!provider.ProjectCodeModel.TryGetCachedFileCodeModel(this.Workspace.GetFilePath(GetDocumentId()), out fileCodeModelHandle))
             {
                 return needMoreTime;
             }

src/VisualStudio/Core/Impl/CodeModel/NodeKeyValidation.cs

@@ -18,7 +18,7 @@ public NodeKeyValidation()
         public void AddProject(AbstractProject project)
         {
             var provider = (IProjectCodeModelProvider)project;
-            IEnumerable<ComHandle<EnvDTE80.FileCodeModel2, FileCodeModel>> fcms = provider.ProjectCodeModel.GetFileCodeModelInstances();
+            var fcms = provider.ProjectCodeModel.GetCachedFileCodeModelInstances();
 
             foreach (var fcm in fcms)
             {

src/VisualStudio/Core/Impl/CodeModel/RootCodeModel.cs

@@ -85,12 +85,11 @@ private Compilation GetCompilation()
 
                 var hostProject = ((VisualStudioWorkspaceImpl)Workspace).ProjectTracker.GetProject(_projectId);
                 var projectCodeModel = ((IProjectCodeModelProvider)hostProject).ProjectCodeModel;
-                return projectCodeModel.GetFileCodeModelInstance(fileName).Value;
-            }
-            else
-            {
-                throw Exceptions.ThrowEInvalidArg();
+
+                return projectCodeModel.GetOrCreateFileCodeModel(fileName);
             }
+
+            throw Exceptions.ThrowEInvalidArg();
         }
 
         public EnvDTE.Project Parent