Exception thrown when stopping a stuck git log session with Alt+Pause

[scaramushe]

Prerequisites

• Write a descriptive title.
• Make sure you are able to repro it on the latest released version
• Search the existing issues, especially the pinned issues.

Exception report

### Environment
PSReadLine: 2.1.0
PowerShell: 5.1.22000.282
OS: Microsoft Windows 10.0.22000
BufferWidth: 138
BufferHeight: 70

Last 200 Keys

 2 e 1 Enter
 g i t Spacebar l o g Spacebar 3 3 9 8 2 e 1 Enter
 UpArrow UpArrow UpArrow DownArrow Ctrl+Backspace - - a b o Tab Enter
 UpArrow UpArrow DownArrow Ctrl+Backspace Backspace Backspace c 5 9 5 5 f 7 0 7 6 8 c 2 2 3 9 1 7 9 b 3 5 5 b 7 b 5 4 6 3 9 1 a 4 a d 6 4 7 7 Enter
 UpArrow UpArrow UpArrow UpArrow Enter
 UpArrow Ctrl+Backspace 6 5 b 9 b 8 2 Enter
 UpArrow Ctrl+Backspace 6 d 7 3 8 e c Enter
 UpArrow Ctrl+LeftArrow Ctrl+Backspace Ctrl+Backspace l o g Spacebar Enter
 q Backspace g i t Spacebar m e r g e t Tab Enter
 UpArrow UpArrow UpArrow UpArrow UpArrow UpArrow UpArrow Enter
 UpArrow UpArrow DownArrow Ctrl+Backspace Backspace Backspace 5 1 f e 6 8 0 6 a b e 7 2 d d 8 9 6 c c 3 d a d 8 3 e c e 3 2 1 7 2 7 3 d b 5 b Enter
 UpArrow UpArrow Enter
 g i t Spacebar l o g Enter
 UpArrow UpArrow UpArrow UpArrow UpArrow Enter
 Alt+Pause

Exception

System.InvalidOperationException: Queue empty.
   at System.ThrowHelper.ThrowInvalidOperationException(ExceptionResource resource)
   at System.Collections.Generic.Queue`1.Dequeue()
   at Microsoft.PowerShell.PSConsoleReadLine.ReadKey()
   at Microsoft.PowerShell.PSConsoleReadLine.InputLoop()
   at Microsoft.PowerShell.PSConsoleReadLine.ReadLine(Runspace runspace, EngineIntrinsics engineIntrinsics, CancellationToken cancellationToken)

Screenshot

Environment data

PS Version: 5.1.22000.282
PS HostName: ConsoleHost (Windows Terminal)
PSReadLine Version: 2.1.0
PSReadLine EditMode: Windows
OS: 10.0.22000.1 (WinBuild.160101.0800)
BufferWidth: 138
BufferHeight: 70

Steps to reproduce

When recovering from issue reproted in microsoft/terminal#12828, pressed Alt+Pause to break out of stuck state.
Then pressed it again and got this error

Expected behavior

No exception

Actual behavior

Exception

[scaramushe]

Another comment - the git autocomplete is posh-git

[daxian-dbw]

This is a very strange issue. I cannot reason from the ReadOneOrMoreKeys method about when it would return with an empty _queuedKeys. Seems impossible to me ...

You mentioned in the windows terminal issue that you pressed Alt+Pause to break out of the unresponsive git log. Did you then, as indicated by your screenshot, start to debug a PowerShell script and press Alt+Pause again which led to the exception? I ask this because your last 200 keys shows Alt+Pause as the last input.

[scaramushe]

Yes, this is the sequence - pressing Alt-Pause to break out and again (for no reason :) ) and getting the error

[StevenBucher98]

Related PowerShell/vscode-powershell#4470

[andyleejordan]

This is a very strange issue. I cannot reason from the ReadOneOrMoreKeys method about when it would return with an empty _queuedKeys. Seems impossible to me ...

You mentioned in the windows terminal issue that you pressed Alt+Pause to break out of the unresponsive git log. Did you then, as indicated by your screenshot, start to debug a PowerShell script and press Alt+Pause again which led to the exception? I ask this because your last 200 keys shows Alt+Pause as the last input.

We were looking at this issue again and the hunch we've got is that the Break key (aka Alt+Pause) is "often translated instantly" in contrast to a key like Ctrl+C where the keyboard buffer still receives input. This would explain why we have nothing to dequeue, because while we expected an input to be queued, nothing was. We'll need to look at what .NET is doing for the Break key.

[ghost]

🎉 This issue was addressed in 3629, which has now been successfully released in v2.3.1-beta1. 🎉