System.NullReferenceException : Object reference not set to an instance of an object.
   at Microsoft.CodeAnalysis.CSharp.Utilities.CSharpUseImplicitTypeHelper.AssignmentSupportsStylePreference(SyntaxToken identifier,TypeSyntax typeName,ExpressionSyntax initializer,SemanticModel semanticModel,OptionSet optionSet,CancellationToken cancellationToken)
   at Microsoft.CodeAnalysis.CSharp.Utilities.CSharpUseImplicitTypeHelper.TryAnalyzeVariableDeclaration(TypeSyntax typeName,SemanticModel semanticModel,OptionSet optionSet,CancellationToken cancellationToken)
   at async Microsoft.CodeAnalysis.CSharp.CodeRefactorings.UseType.AbstractUseTypeCodeRefactoringProvider.ComputeRefactoringsAsync(<Unknown Parameters>)
   at async Microsoft.CodeAnalysis.CodeRefactorings.CodeRefactoringService.GetRefactoringFromProviderAsync(<Unknown Parameters>)
   at Microsoft.VisualStudio.Telemetry.WindowsErrorReporting.WatsonReport.GetClrWatsonExceptionInfo(Exception exceptionObject)