Feature 'Semantic classification' is currently unavailable due to an internal error (StreamJsonRpc.RemoteInvocationException: Object reference not set to an instance of an object.) #63567
Description
Version Used: Visual Studio 17.3.0 (for a about a week so far)
Steps to Reproduce: Routine C# coding. This popped while I was in the middle of splitting a for loop into two for loops (which may not be relevant at all) and seemed perhaps worth noting. While analyzers going offline due to exceptions isn't uncommon this is the first time I've had this particular analyzer fall over.
Expected Behavior: Semantic classification doesn't render itself unavailable.
Actual Behavior: VS raises yellow bar with message in the title and the stack trace below. Looked around a bit in %AppData%\Microsoft\VisualStudio and didn't see anything which looked like helpful additional information but please let me know if there's a log file I should consult.
StreamJsonRpc.RemoteInvocationException: Object reference not set to an instance of an object.
at StreamJsonRpc.JsonRpc.<InvokeCoreAsync>d__143`1.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at System.Threading.Tasks.ValueTask`1.get_Result()
at Microsoft.CodeAnalysis.Remote.BrokeredServiceConnection`1.<TryInvokeAsync>d__18`1.MoveNext()
RPC server exception:
System.NullReferenceException: Object reference not set to an instance of an object.
at Microsoft.CodeAnalysis.CSharp.SyntaxTreeSemanticModel.<CreateModelForAttribute>g__getAttributeTarget|79_0(SyntaxNode targetSyntax)
at Microsoft.CodeAnalysis.CSharp.SyntaxTreeSemanticModel.CreateModelForAttribute(Binder enclosingBinder, AttributeSyntax attribute, MemberSemanticModel containingModel)
at Microsoft.CodeAnalysis.CSharp.SyntaxTreeSemanticModel.CreateMemberModel(CSharpSyntaxNode node)
at System.Collections.Immutable.ImmutableInterlocked.GetOrAdd[TKey,TValue](ImmutableDictionary`2& location, TKey key, Func`2 valueFactory)
at Microsoft.CodeAnalysis.CSharp.SyntaxTreeSemanticModel.GetOrAddModel(CSharpSyntaxNode node)
at Microsoft.CodeAnalysis.CSharp.SyntaxTreeSemanticModel.GetMemberModel(SyntaxNode node)
at Microsoft.CodeAnalysis.CSharp.SyntaxTreeSemanticModel.GetSymbolInfoWorker(CSharpSyntaxNode node, SymbolInfoOptions options, CancellationToken cancellationToken)
at Microsoft.CodeAnalysis.CSharp.CSharpSemanticModel.GetSymbolInfo(ExpressionSyntax expression, CancellationToken cancellationToken)
at Microsoft.CodeAnalysis.CSharp.CSharpExtensions.GetSymbolInfo(SemanticModel semanticModel, ExpressionSyntax expression, CancellationToken cancellationToken)
at Microsoft.CodeAnalysis.CSharp.Classification.Classifiers.NameSyntaxClassifier.ClassifyTypeSyntax(NameSyntax name, SemanticModel semanticModel, ArrayBuilder`1 result, CancellationToken cancellationToken)
at Microsoft.CodeAnalysis.CSharp.Classification.Classifiers.NameSyntaxClassifier.AddClassifications(SyntaxNode syntax, SemanticModel semanticModel, ClassificationOptions options, ArrayBuilder`1 result, CancellationToken cancellationToken)
at Microsoft.CodeAnalysis.Classification.AbstractSyntaxClassificationService.Worker.ClassifyNode(SyntaxNode syntax)
at Microsoft.CodeAnalysis.Classification.AbstractSyntaxClassificationService.Worker.ProcessNodes()
at Microsoft.CodeAnalysis.Classification.AbstractSyntaxClassificationService.Worker.Classify(SemanticModel semanticModel, TextSpan textSpan, ArrayBuilder`1 list, Func`2 getNodeClassifiers, Func`2 getTokenClassifiers, ClassificationOptions options, CancellationToken cancellationToken)
at Microsoft.CodeAnalysis.Classification.AbstractSyntaxClassificationService.<AddSemanticClassificationsAsync>d__6.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at Microsoft.CodeAnalysis.Classification.AbstractClassificationService.<AddClassificationsInCurrentProcessAsync>d__7.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at Microsoft.CodeAnalysis.Remote.RemoteSemanticClassificationService.<>c__DisplayClass20_0.<<GetClassificationsAsync>b__0>d.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at System.Threading.Tasks.ValueTask`1.get_Result()
at Microsoft.CodeAnalysis.Remote.RemoteWorkspace.<>c__DisplayClass10_0`1.<<RunWithSolutionAsync>g__TryFastGetSolutionAndRunAsync|0>d.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at System.Threading.Tasks.ValueTask`1.get_Result()
at Microsoft.CodeAnalysis.Remote.RemoteWorkspace.<RunWithSolutionAsync>d__10`1.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at System.Threading.Tasks.ValueTask`1.get_Result()
at Microsoft.CodeAnalysis.Remote.BrokeredServiceBase.<RunWithSolutionAsync>d__11`1.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at System.Threading.Tasks.ValueTask`1.get_Result()
at Microsoft.CodeAnalysis.Remote.BrokeredServiceBase.<RunServiceImplAsync>d__14`1.MoveNext()