CodeAnalysis.ChangeNamespace ArgumentException

[tamlin-mike]

Version Used: VS 16.11.5

On a class not within a namespace, in a project with a dash ('-') in its name, invoking Alt+Returns and by keyboard scrolling past the "Move to namespace" suggestion
displaying the (indeed C#-illegal) project name (or if it's directory name - both were the same) resulted in the following.

System.ArgumentException : targetNamespace
   at async Microsoft.CodeAnalysis.ChangeNamespace.AbstractChangeNamespaceService`3.ChangeNamespaceAsync[TNamespaceDeclarationSyntax,TCompilationUnitSyntax,TMemberDeclarationSyntax](<Unknown Parameters>)
   at async Microsoft.CodeAnalysis.CodeActions.CodeAction.ComputeOperationsAsync(<Unknown Parameters>)
   at async Microsoft.CodeAnalysis.CodeActions.CodeAction.GetPreviewOperationsAsync(<Unknown Parameters>)
   at async Microsoft.CodeAnalysis.Editor.Implementation.Suggestions.SuggestedAction.GetPreviewResultAsync(<Unknown Parameters>)
   at async Microsoft.CodeAnalysis.Editor.Implementation.Suggestions.SuggestedActionWithNestedFlavors.<>c__DisplayClass11_0.<GetPreviewAsync>b__0(<Unknown Parameters>)
   at async Microsoft.CodeAnalysis.Extensions.IExtensionManagerExtensions.PerformFunctionAsync[T](<Unknown Parameters>)
   at Microsoft.VisualStudio.Telemetry.WindowsErrorReporting.WatsonReport.GetClrWatsonExceptionInfo(Exception exceptionObject)