System.InvalidOperationException: Queue empty when using PSReadLine in VSCode

[ukbendavies]

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

Last 101 Keys:

pipmo ave<Tab>dap<Tab><Backspace><Enter>
get-mo<Tab><Enter>
pppppget-modules<Enter>
get-modu<Tab><Enter>
remove-mo<Tab> dap<Tab><Enter>
ppp<DownArrow><UpArrow><UpArrow><UpArrow><Enter>
pppppppppppppppppppppppp

Exception:

System.InvalidOperationException: Queue empty.
   at System.Collections.Generic.Queue`1.ThrowForEmptyQueue()
   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, Nullable`1 lastRunStatus)

Screenshot

Environment:

PSReadLine: 2.4.0-beta0+923a890f2e7ea10465f3a80a2bc030121a1c2f68
PowerShell: 2025.0.0
OS: Microsoft Windows 11 Enterprise 24H2 (10.0.26100)
BufferWidth: 141
BufferHeight: 16
Locale                                    : 0809
Manufacturer                              : Microsoft Corporation
MUILanguages                              : {en-GB, en-US}


Note: The keys that follow were not repeated / stuck keys but it seems to have key repetitions?

Last 101 Keys:

pipmo ave<Tab>dap<Tab><Backspace><Enter>
get-mo<Tab><Enter>
pppppget-modules<Enter>
get-modu<Tab><Enter>
remove-mo<Tab> dap<Tab><Enter>
ppp<DownArrow><UpArrow><UpArrow><UpArrow><Enter>
pppppppppppppppppppppppp

Exception:

System.InvalidOperationException: Queue empty.
   at System.Collections.Generic.Queue`1.ThrowForEmptyQueue()
   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, Nullable`1 lastRunStatus)

Additional Context: This occurred during normal usage in VSCode. It seems to be related to command history navigation or tab completion. No custom PSReadLine configuration was applied.

Environment data

Inside VSCode terminal:
PS Version: 7.5.0
PS HostName: Visual Studio Code Host
PSReadLine Version: 2.4.0-beta0
PSReadLine EditMode: Windows
OS: 10.0.26100.1 (WinBuild.160101.0800)
BufferWidth: 195
BufferHeight: 11

Windows Terminal with Powershell 7:

PS Version: 7.5.1
PS HostName: ConsoleHost (Windows Terminal)
PSReadLine Version: 2.3.6
PSReadLine EditMode: Windows
OS: 10.0.26100.1 (WinBuild.160101.0800)
BufferWidth: 115
BufferHeight: 65

Steps to reproduce

• Open VSCode with PowerShell terminal.
• Run a series of commands involving pip, get-module, and remove-module.
• Use arrow keys to navigate command history.
• Observe crash.

Note: this seems to occur when using vscode with normal editor input, the workflow I was using on the day of the exception ran multiple pwsh instances because of pester test execution in the test extension. not sure if this was a contributing factor though.

Expected behavior

No exception, VSCode does not exhibit odd behaviors like starting a debugging session when any key on the keyboard is pressed

Actual behavior

VSCode starts running arbitrary debugging sessions (F5) and at some point the Exception occurs.

[daxian-dbw]

This is another "Queue empty" exception in VSCode, which seems to happen when running debugging sessions.

@SeeminglyScience fixed a race condition (PR #3294) that caused re-entering PSReadLine (see #3292 (comment)), which resulted in the "Queue empty" exception. I'm not sure if this is another form of the re-entry issue.