VS Code Powershell Editor Services Throws Exception If Powershell Profile Contains ErrorActionPreference=Stop

[caparkaya]

Prerequisites

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

Steps to reproduce

Hello,

With the latest update of VS Code (v1.74.1) Powershell Extension (v2022.12.1), with Terminal > Integrated > Shell Integration: Enabled (Checked), Powershell Editor Services throws exception at startup if the powershell profile script file (Microsoft.VSCode_profile.ps1) contains

$ErrorActionPreference = "Stop"; Set-StrictMode -Version Latest

It fails in file "src/PowerShellEditorServices/Services/PowerShell/Host/PsesInternalHost.cs", at line 567 (function Global:Prompt()):

$Global:__LastHistoryId = $LastHistoryEntry.Id

because $LastHistoryEntry is null. Looking at the code fragment, I understand that at line 529 the assignment statement might result in $null value (or the resulting object might not contain Id property) which is not handled properly.

Expected behavior

Setting

$ErrorActionPreference = "Stop"; Set-StrictMode -Version Latest

in powershell profile script should not cause any startup errors inside Powershell Editor Services.

Actual behavior

At editor services startup (with Powershell profile loaded in terminal):

The property 'Id' cannot be found on this object. Verify that the property exists.
At line:57 char:2
+     $Global:__LastHistoryId = $LastHistoryEntry.Id
+     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    + CategoryInfo          : NotSpecified: (:) [], ParentContainsErrorRecordException
    + FullyQualifiedErrorId : PropertyNotFoundStrict

Error details

[Warn  - 12:01:11] Microsoft.PowerShell.EditorServices.Services.PowerShell.Host.PsesInternalHost: Runtime exception occurred while executing command:

System.Management.Automation.RuntimeException: The variable '$IsWindows' cannot be retrieved because it has not been set.
   at System.Management.Automation.Runspaces.PipelineBase.Invoke(IEnumerable input)
   at System.Management.Automation.PowerShell.Worker.ConstructPipelineAndDoWork(Runspace rs, Boolean performSyncInvoke)
   at System.Management.Automation.PowerShell.Worker.CreateRunspaceIfNeededAndDoWork(Runspace rsToUse, Boolean isSync)
   at System.Management.Automation.PowerShell.CoreInvokeHelper[TInput,TOutput](PSDataCollection`1 input, PSDataCollection`1 output, PSInvocationSettings settings)
   at System.Management.Automation.PowerShell.CoreInvoke[TInput,TOutput](PSDataCollection`1 input, PSDataCollection`1 output, PSInvocationSettings settings)
   at System.Management.Automation.PowerShell.Invoke[T](IEnumerable input, PSInvocationSettings settings)
   at Microsoft.PowerShell.EditorServices.Services.PowerShell.Utility.PowerShellExtensions.InvokeAndClear[TResult](PowerShell pwsh, PSInvocationSettings invocationSettings)
   at Microsoft.PowerShell.EditorServices.Services.PowerShell.Execution.SynchronousPowerShellTask`1.ExecuteNormally(CancellationToken cancellationToken) | 
[Error - 12:01:11] OmniSharp.Extensions.JsonRpc.DefaultRequestInvoker: Failed to handle request initialize 0 - System.Management.Automation.RuntimeException: The variable '$IsWindows' cannot be retrieved because it has not been set.
   at System.Management.Automation.Runspaces.PipelineBase.Invoke(IEnumerable input)
   at System.Management.Automation.PowerShell.Worker.ConstructPipelineAndDoWork(Runspace rs, Boolean performSyncInvoke)
   at System.Management.Automation.PowerShell.Worker.CreateRunspaceIfNeededAndDoWork(Runspace rsToUse, Boolean isSync)
   at System.Management.Automation.PowerShell.CoreInvokeHelper[TInput,TOutput](PSDataCollection`1 input, PSDataCollection`1 output, PSInvocationSettings settings)
   at System.Management.Automation.PowerShell.CoreInvoke[TInput,TOutput](PSDataCollection`1 input, PSDataCollection`1 output, PSInvocationSettings settings)
   at System.Management.Automation.PowerShell.Invoke[T](IEnumerable input, PSInvocationSettings settings)
   at Microsoft.PowerShell.EditorServices.Services.PowerShell.Utility.PowerShellExtensions.InvokeAndClear[TResult](PowerShell pwsh, PSInvocationSettings invocationSettings)
   at Microsoft.PowerShell.EditorServices.Services.PowerShell.Execution.SynchronousPowerShellTask`1.ExecuteNormally(CancellationToken cancellationToken)
   at Microsoft.PowerShell.EditorServices.Services.PowerShell.Execution.SynchronousPowerShellTask`1.Run(CancellationToken cancellationToken)
   at Microsoft.PowerShell.EditorServices.Services.PowerShell.Execution.SynchronousTask`1.ExecuteSynchronously(CancellationToken executorCancellationToken)
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at Microsoft.PowerShell.EditorServices.Services.PowerShell.Host.PsesInternalHost.<TryStartAsync>d__81.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at OmniSharp.Extensions.LanguageServer.Server.LanguageServer.<MediatR-IRequestHandler<OmniSharp-Extensions-LanguageServer-Protocol-Models-InternalInitializeParams\,OmniSharp-Extensions-LanguageServer-Protocol-Models-InitializeResult>-Handle>d__78.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at OmniSharp.Extensions.LanguageServer.Server.Pipelines.SemanticTokensDeltaPipeline`2.<Handle>d__0.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at OmniSharp.Extensions.LanguageServer.Server.Pipelines.ResolveCommandPipeline`2.<Handle>d__3.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at MediatR.Pipeline.RequestPreProcessorBehavior`2.<Handle>d__2.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at MediatR.Pipeline.RequestPostProcessorBehavior`2.<Handle>d__2.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at MediatR.Pipeline.RequestExceptionProcessorBehavior`2.<Handle>d__2.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at MediatR.Pipeline.RequestExceptionProcessorBehavior`2.<Handle>d__2.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at MediatR.Pipeline.RequestExceptionActionProcessorBehavior`2.<Handle>d__2.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at MediatR.Pipeline.RequestExceptionActionProcessorBehavior`2.<Handle>d__2.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at OmniSharp.Extensions.JsonRpc.RequestRouterBase`1.<<RouteRequest>g__InnerRoute|7_0>d.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at OmniSharp.Extensions.JsonRpc.RequestRouterBase`1.<RouteRequest>d__7.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at OmniSharp.Extensions.JsonRpc.DefaultRequestInvoker.<>c__DisplayClass10_0.<<RouteRequest>b__5>d.MoveNext() | Method='initialize' RequestId='0'
[Warn  - 12:01:11] Microsoft.PowerShell.EditorServices.Services.PowerShell.Host.PsesInternalHost: Runtime exception occurred while executing command:

System.Management.Automation.PropertyNotFoundException: The property 'Id' cannot be found on this object. Verify that the property exists.
   at System.Management.Automation.Runspaces.PipelineBase.Invoke(IEnumerable input)
   at System.Management.Automation.PowerShell.Worker.ConstructPipelineAndDoWork(Runspace rs, Boolean performSyncInvoke)
   at System.Management.Automation.PowerShell.Worker.CreateRunspaceIfNeededAndDoWork(Runspace rsToUse, Boolean isSync)
   at System.Management.Automation.PowerShell.CoreInvokeHelper[TInput,TOutput](PSDataCollection`1 input, PSDataCollection`1 output, PSInvocationSettings settings)
   at System.Management.Automation.PowerShell.CoreInvoke[TInput,TOutput](PSDataCollection`1 input, PSDataCollection`1 output, PSInvocationSettings settings)
   at System.Management.Automation.PowerShell.Invoke[T](IEnumerable input, PSInvocationSettings settings)
   at Microsoft.PowerShell.EditorServices.Services.PowerShell.Utility.PowerShellExtensions.InvokeAndClear[TResult](PowerShell pwsh, PSInvocationSettings invocationSettings)
   at Microsoft.PowerShell.EditorServices.Services.PowerShell.Execution.SynchronousPowerShellTask`1.ExecuteNormally(CancellationToken cancellationToken) | 
[Warn  - 12:01:11] OmniSharp.Extensions.LanguageServer.Server.LspServerOutputFilter: Tried to send request or notification before initialization was completed and will be sent later OmniSharp.Extensions.JsonRpc.Server.Messages.InternalError | @Request='OmniSharp.Extensions.JsonRpc.Server.Messages.InternalError'

Environment data

Name                           Value
----                           -----
PSVersion                      5.1.19041.1682
PSEdition                      Desktop
PSCompatibleVersions           {1.0, 2.0, 3.0, 4.0...}
BuildVersion                   10.0.19041.1682
CLRVersion                     4.0.30319.42000
WSManStackVersion              3.0
PSRemotingProtocolVersion      2.3
SerializationVersion           1.1.0.1

Version

Powershell Extension Version: v2022.12.1, VSCode Version: 1.74.1

Visuals

No response

[ninmonkey]

At the end of the first pass, It looks like it sets the global to null

 $Global:__LastHistoryId = $LastHistoryEntry.Id # which is null

pass 1:

• sets $Global:__LastHistoryId = -1
• fails test: if ( $Global:__LastHistoryId -ne -1 ) { }
  • because -1 -ne -1
• sets $Global:__LastHistoryId = $null

pass 2:

• pass test: if ( $Global:__LastHistoryId -ne -1 ) { }
  • because $null -ne -1
• this time LastHistoryEntry has a value
• fails $LastHistoryEntry.Id -eq $Global:__LastHistoryId
  • because <any int> -eq $null
• sets $Global:__LastHistoryId = $LastHistoryEntry.Id
  • therefore $Global:__LastHistoryId == <any int>

pass 3

• global stabilizes, things are okay from now on?

---

My annotations are the 🦓-comments. The rest is the truncated original.

# Prevent installing more than once per session
if (Test-Path variable:global:__VSCodeOriginalPrompt) {
    return;
}
# Disable shell integration when the language mode is restricted
if ($ExecutionContext.SessionState.LanguageMode -ne "FullLanguage") {
    return;
}
$Global:__VSCodeOriginalPrompt = $function:Prompt
$Global:__LastHistoryId = -1
function Global:Prompt() {
    $FakeCode = [int]!$global:?
    $LastHistoryEntry = Get-History -Count 1 
    # 🦓 $LastHistoryEntry: is true null

    # Skip finishing the command if the first command has not yet started
    if ($Global:__LastHistoryId -ne -1) {
        # 🦓 -1 -ne -1 == false
        
        if ($LastHistoryEntry.Id -eq $Global:__LastHistoryId) {
            # if entered 🦓 $null.Id -eq -1 == false            

        }
        else {
            # if entered then 🦓 that means: $Global:__LastHistoryId != -1
            $Result = '..'
            
            if ($LastHistoryEntry.CommandLine) {
                #🦓 if $null , therefore: false
                $CommandLine = $LastHistoryEntry.CommandLine
            }
            else {
                $CommandLine = ""
            }
        }
    }
    $Result += $Global:__VSCodeOriginalPrompt.Invoke()
    $Global:__LastHistoryId = $LastHistoryEntry.Id
    # 🦓 $global:__lastHistoryId = $null 
    return $Result
}

[caparkaya]

Thank you @ninmonkey , I'm not much familiar with this process but I understand that you were able to repro this issue. Should I propose a code-based solution & open a pull-request myself or will someone from the dev-team do this within a time-frame upon availability?
I may not be able to see how my proposed solution will affect in the big picture, that's the reason of my hesitation.

[andyleejordan]

This should be resolved. The problem was actually the use of Set-StrictMode -Version Latest being incompatible with how the VS Code team wrote their shell integration script. We worked around it by adding:

	# NOTE: We disable strict mode for the scope of this function because it unhelpfully throws an
	# error when $LastHistoryEntry is null, and is not otherwise useful.
	Set-StrictMode -Off

to the prompt wrapper in that script.

[ghost]

This issue has been marked as answered and has not had any activity in a day. It has been automatically closed for housekeeping purposes.