Roslyn: Visual Studio crashes when adding a parameter to a function

[vsfeedback]

_This issue has been moved from a ticket on Developer Community._

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[regression] [worked-in:16.4]
I have a method with two overloads:

Private Function MonthToActualYearMonth(ByVal theMonth As MyEnumType) As Integer
Public Shared Function MonthToActualYearMonth(ByVal theYear As Integer, ByVal theMonth As MyEnumType) As Integer

And a line of code calling the wrong method:
Dim aBla = MonthToActualYearMonth(myMonth)

I get a squigly red line underneath the method call with the following error (which is correct):
Cannot refer to an instance member of a class from within a shared method or shared member initializer without an explicit instance of the class.

I want to add the missing parameter to use the shared method instead of the private function. I add my cursor after the first parentheses and start typing to add the missing parameter. When I finally type the "," Visual Studio crashes.

In the Event Viewer in Windows I find the following back:

Application: devenv.exe
Framework Version: v4.0.30319
Description: The application requested process termination through System.Environment.FailFast(string message).
Message: System.ArgumentOutOfRangeException: Index was out of range. Must be non-negative and less than the size of the collection.
Parameter name: index
   at System.ThrowHelper.ThrowArgumentOutOfRangeException(ExceptionArgument argument, ExceptionResource resource)
   at System.Collections.Generic.List`1.get_Item(Int32 index)
   at Microsoft.CodeAnalysis.SignatureHelp.AbstractSignatureHelpProvider.Filter(IList`1 items, IEnumerable`1 parameterNames, Nullable`1 selectedItem)
   at Microsoft.CodeAnalysis.SignatureHelp.AbstractSignatureHelpProvider.CreateSignatureHelpItems(IList`1 items, TextSpan applicableSpan, SignatureHelpState state, Nullable`1 selectedItem)
   at Microsoft.CodeAnalysis.VisualBasic.SignatureHelp.InvocationExpressionSignatureHelpProvider.VB$StateMachine_16_GetItemsWorkerAsync.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.ValidateEnd(Task task)
   at Microsoft.CodeAnalysis.SignatureHelp.AbstractSignatureHelpProvider.<GetItemsAsync>d__16.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Microsoft.CodeAnalysis.Editor.Implementation.IntelliSense.SignatureHelp.Controller.Session.<ComputeItemsAsync>d__9.MoveNext()
Stack:
   at System.Environment.FailFast(System.String, System.Exception)
   at Microsoft.CodeAnalysis.FailFast.OnFatalException(System.Exception)
   at Microsoft.CodeAnalysis.ErrorReporting.FatalError.Report(System.Exception, System.Action`1<System.Exception>)
   at Microsoft.CodeAnalysis.ErrorReporting.FatalError.ReportUnlessCanceled(System.Exception)
   at Microsoft.CodeAnalysis.Editor.Implementation.IntelliSense.SignatureHelp.Controller+Session+<ComputeItemsAsync>d__9.MoveNext()
   at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(System.Threading.Tasks.Task)
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(System.Threading.Tasks.Task)
   at Microsoft.CodeAnalysis.Editor.Implementation.IntelliSense.SignatureHelp.Controller+Session+<ComputeItemsAsync>d__9.MoveNext()
   at System.Runtime.CompilerServices.AsyncTaskMethodBuilder`1[[System.ValueTuple`2[[System.__Canon, mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089],[System.__Canon, mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089]], mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089]].Start[[Microsoft.CodeAnalysis.Editor.Implementation.IntelliSense.SignatureHelp.Controller+Session+<ComputeItemsAsync>d__9, Microsoft.CodeAnalysis.EditorFeatures, Version=3.4.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35]](<ComputeItemsAsync>d__9 ByRef)
   at Microsoft.CodeAnalysis.Editor.Implementation.IntelliSense.SignatureHelp.Controller+Session.ComputeItemsAsync(System.Collections.Immutable.ImmutableArray`1<Microsoft.CodeAnalysis.SignatureHelp.ISignatureHelpProvider>, Microsoft.VisualStudio.Text.SnapshotPoint, Microsoft.CodeAnalysis.SignatureHelp.SignatureHelpTriggerInfo, Microsoft.CodeAnalysis.Document, System.Threading.CancellationToken)
   at Microsoft.CodeAnalysis.Editor.Implementation.IntelliSense.SignatureHelp.Controller+Session+<ComputeModelInBackgroundAsync>d__4.MoveNext()
   at System.Runtime.CompilerServices.AsyncTaskMethodBuilder`1[[System.__Canon, mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089]].Start[[Microsoft.CodeAnalysis.Editor.Implementation.IntelliSense.SignatureHelp.Controller+Session+<ComputeModelInBackgroundAsync>d__4, Microsoft.CodeAnalysis.EditorFeatures, Version=3.4.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35]](<ComputeModelInBackgroundAsync>d__4 ByRef)
   at Microsoft.CodeAnalysis.Editor.Implementation.IntelliSense.SignatureHelp.Controller+Session.ComputeModelInBackgroundAsync(Microsoft.CodeAnalysis.Editor.Implementation.IntelliSense.SignatureHelp.Model, System.Collections.Immutable.ImmutableArray`1<Microsoft.CodeAnalysis.SignatureHelp.ISignatureHelpProvider>, Microsoft.VisualStudio.Text.SnapshotPoint, Microsoft.CodeAnalysis.Editor.Implementation.IntelliSense.DisconnectedBufferGraph, Microsoft.CodeAnalysis.SignatureHelp.SignatureHelpTriggerInfo, System.Threading.CancellationToken)
   at Microsoft.CodeAnalysis.Editor.Implementation.IntelliSense.SignatureHelp.Controller+Session+<>c__DisplayClass3_0.<ComputeModel>b__0(Microsoft.CodeAnalysis.Editor.Implementation.IntelliSense.SignatureHelp.Model, System.Threading.CancellationToken)
   at Microsoft.CodeAnalysis.Editor.Implementation.IntelliSense.ModelComputation`1+<>c__DisplayClass17_0[[System.__Canon, mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089]].<ChainTaskAndNotifyControllerWhenFinished>b__0(System.Threading.Tasks.Task`1<System.__Canon>)
   at Roslyn.Utilities.TaskExtensions+<>c__DisplayClass15_0`2[[System.__Canon, mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089],[System.__Canon, mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089]].<SafeContinueWithFromAsync>b__0(System.Threading.Tasks.Task)
   at System.Threading.Tasks.ContinuationResultTaskFromTask`1[[System.__Canon, mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089]].InnerInvoke()
   at System.Threading.Tasks.Task.Execute()
   at System.Threading.Tasks.Task.ExecutionContextCallback(System.Object)
   at System.Threading.ExecutionContext.RunInternal(System.Threading.ExecutionContext, System.Threading.ContextCallback, System.Object, Boolean)
   at System.Threading.ExecutionContext.Run(System.Threading.ExecutionContext, System.Threading.ContextCallback, System.Object, Boolean)
   at System.Threading.Tasks.Task.ExecuteWithThreadLocal(System.Threading.Tasks.Task ByRef)
   at System.Threading.Tasks.Task.ExecuteEntry(Boolean)
   at System.Threading.Tasks.Task.System.Threading.IThreadPoolWorkItem.ExecuteWorkItem()
   at System.Threading.ThreadPoolWorkQueue.Dispatch()
   at System.Threading._ThreadPoolWaitCallback.PerformWaitCallback()

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Original Comments

Visual Studio Feedback System on 12/13/2019, 02:00 AM:

We have directed your feedback to the appropriate engineering team for further evaluation. The team will review the feedback and notify you about the next steps.

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Original Solutions

(no solutions)

[dpoeschl]

Simple standalone repro:

Class C
    Shared Sub Test()
        M(1, 2) ' Show Signature Help on this invocation (Ctrl+Shift+Space) or try typing the invocation from scratch
    End Sub

    Sub M(y As Integer)
    End Sub

    Shared Sub M(x As Integer, y As Integer)
    End Sub
End Class

[dpoeschl]

This would be a great opportunity to make sure this feature doesn't corrupt state and then remove the failfasts.