Pass CancellationToken instead of CancellationTokenSource

src/Features/Core/Portable/SolutionCrawler/WorkCoordinator.AsyncWorkItemQueue.cs

@@ -177,19 +177,19 @@ protected void Cancel_NoLock(object key)
                     }
                 }
 
-                public bool TryTake(TKey key, out WorkItem workInfo, out CancellationTokenSource source)
+                public bool TryTake(TKey key, out WorkItem workInfo, out CancellationToken cancellationToken)
                 {
                     lock (_gate)
                     {
                         if (TryTake_NoLock(key, out workInfo))
                         {
-                            source = GetNewCancellationSource_NoLock(key);
+                            cancellationToken = GetNewCancellationToken_NoLock(key);
                             workInfo.AsyncToken.Dispose();
                             return true;
                         }
                         else
                         {
-                            source = null;
+                            cancellationToken = CancellationToken.None;
                             return false;
                         }
                     }
@@ -199,33 +199,33 @@ public bool TryTake(TKey key, out WorkItem workInfo, out CancellationTokenSource
                     ProjectId preferableProjectId,
                     ProjectDependencyGraph dependencyGraph,
                     IDiagnosticAnalyzerService analyzerService,
-                    out WorkItem workItem, out CancellationTokenSource source)
+                    out WorkItem workItem, out CancellationToken cancellationToken)
                 {
                     lock (_gate)
                     {
                         // there must be at least one item in the map when this is called unless host is shutting down.
                         if (TryTakeAnyWork_NoLock(preferableProjectId, dependencyGraph, analyzerService, out workItem))
                         {
-                            source = GetNewCancellationSource_NoLock(workItem.Key);
+                            cancellationToken = GetNewCancellationToken_NoLock(workItem.Key);
                             workItem.AsyncToken.Dispose();
                             return true;
                         }
                         else
                         {
-                            source = null;
+                            cancellationToken = CancellationToken.None;
                             return false;
                         }
                     }
                 }
 
-                protected CancellationTokenSource GetNewCancellationSource_NoLock(object key)
+                protected CancellationToken GetNewCancellationToken_NoLock(object key)
                 {
                     Debug.Assert(!_cancellationMap.ContainsKey(key));
 
                     var source = new CancellationTokenSource();
                     _cancellationMap.Add(key, source);
 
-                    return source;
+                    return source.Token;
                 }
 
                 protected ProjectId GetBestProjectId_NoLock<T>(

src/Features/Core/Portable/SolutionCrawler/WorkCoordinator.HighPriorityProcessor.cs

@@ -124,13 +124,13 @@ protected override async Task ExecuteAsync()
                         }
                     }
 
-                    private bool GetNextWorkItem(out WorkItem workItem, out CancellationTokenSource documentCancellation)
+                    private bool GetNextWorkItem(out WorkItem workItem, out CancellationToken cancellationToken)
                     {
                         // GetNextWorkItem since it can't fail. we still return bool to confirm that this never fail.
                         var documentId = _processor._documentTracker.TryGetActiveDocument();
                         if (documentId != null)
                         {
-                            if (_workItemQueue.TryTake(documentId, out workItem, out documentCancellation))
+                            if (_workItemQueue.TryTake(documentId, out workItem, out cancellationToken))
                             {
                                 return true;
                             }
@@ -141,10 +141,10 @@ private bool GetNextWorkItem(out WorkItem workItem, out CancellationTokenSource
                             dependencyGraph: _processor.DependencyGraph,
                             analyzerService: _processor.DiagnosticAnalyzerService,
                             workItem: out workItem,
-                            source: out documentCancellation);
+                            cancellationToken: out cancellationToken);
                     }
 
-                    private async Task ProcessDocumentAsync(Solution solution, ImmutableArray<IIncrementalAnalyzer> analyzers, WorkItem workItem, CancellationTokenSource source)
+                    private async Task ProcessDocumentAsync(Solution solution, ImmutableArray<IIncrementalAnalyzer> analyzers, WorkItem workItem, CancellationToken cancellationToken)
                     {
                         if (this.CancellationToken.IsCancellationRequested)
                         {
@@ -156,9 +156,8 @@ private async Task ProcessDocumentAsync(Solution solution, ImmutableArray<IIncre
 
                         try
                         {
-                            using (Logger.LogBlock(FunctionId.WorkCoordinator_ProcessDocumentAsync, w => w.ToString(), workItem, source.Token))
+                            using (Logger.LogBlock(FunctionId.WorkCoordinator_ProcessDocumentAsync, w => w.ToString(), workItem, cancellationToken))
                             {
-                                var cancellationToken = source.Token;
                                 var document = solution.GetDocument(documentId);
                                 if (document != null)
                                 {

src/Features/Core/Portable/SolutionCrawler/WorkCoordinator.LowPriorityProcessor.cs

@@ -114,7 +114,7 @@ private void CancelRunningTaskIfHigherQueueHasWorkItem()
                         _workItemQueue.RequestCancellationOnRunningTasks();
                     }
 
-                    private async Task ProcessProjectAsync(ImmutableArray<IIncrementalAnalyzer> analyzers, WorkItem workItem, CancellationTokenSource source)
+                    private async Task ProcessProjectAsync(ImmutableArray<IIncrementalAnalyzer> analyzers, WorkItem workItem, CancellationToken cancellationToken)
                     {
                         if (this.CancellationToken.IsCancellationRequested)
                         {
@@ -128,10 +128,8 @@ private async Task ProcessProjectAsync(ImmutableArray<IIncrementalAnalyzer> anal
 
                         try
                         {
-                            using (Logger.LogBlock(FunctionId.WorkCoordinator_ProcessProjectAsync, w => w.ToString(), workItem, source.Token))
+                            using (Logger.LogBlock(FunctionId.WorkCoordinator_ProcessProjectAsync, w => w.ToString(), workItem, cancellationToken))
                             {
-                                var cancellationToken = source.Token;
-
                                 var project = processingSolution.GetProject(projectId);
                                 if (project != null)
                                 {
@@ -195,14 +193,12 @@ public override void Shutdown()
 
                     internal void WaitUntilCompletion_ForTestingPurposesOnly(ImmutableArray<IIncrementalAnalyzer> analyzers, List<WorkItem> items)
                     {
-                        CancellationTokenSource source = new CancellationTokenSource();
-
                         var uniqueIds = new HashSet<ProjectId>();
                         foreach (var item in items)
                         {
                             if (uniqueIds.Add(item.ProjectId))
                             {
-                                ProcessProjectAsync(analyzers, item, source).Wait();
+                                ProcessProjectAsync(analyzers, item, CancellationToken.None).Wait();
                             }
                         }
                     }

src/Features/Core/Portable/SolutionCrawler/WorkCoordinator.NormalPriorityProcessor.cs

@@ -301,7 +301,7 @@ private void RemoveHigherPriorityDocument(DocumentId documentId)
                         }
                     }
 
-                    private async Task ProcessDocumentAsync(ImmutableArray<IIncrementalAnalyzer> analyzers, WorkItem workItem, CancellationTokenSource source)
+                    private async Task ProcessDocumentAsync(ImmutableArray<IIncrementalAnalyzer> analyzers, WorkItem workItem, CancellationToken cancellationToken)
                     {
                         if (this.CancellationToken.IsCancellationRequested)
                         {
@@ -332,9 +332,8 @@ private async Task ProcessDocumentAsync(ImmutableArray<IIncrementalAnalyzer> ana
                         var solution = this.Processor.CurrentSolution;
                         try
                         {
-                            using (Logger.LogBlock(FunctionId.WorkCoordinator_ProcessDocumentAsync, w => w.ToString(), workItem, source.Token))
+                            using (Logger.LogBlock(FunctionId.WorkCoordinator_ProcessDocumentAsync, w => w.ToString(), workItem, cancellationToken))
                             {
-                                var cancellationToken = source.Token;
                                 var document = solution.GetDocument(documentId);
 
                                 if (document != null)
@@ -542,11 +541,9 @@ public override void Shutdown()
 
                     internal void WaitUntilCompletion_ForTestingPurposesOnly(ImmutableArray<IIncrementalAnalyzer> analyzers, List<WorkItem> items)
                     {
-                        CancellationTokenSource source = new CancellationTokenSource();
-
                         foreach (var item in items)
                         {
-                            ProcessDocumentAsync(analyzers, item, source).Wait();
+                            ProcessDocumentAsync(analyzers, item, CancellationToken.None).Wait();
                         }
                     }