$LASTEXITCODE does not get set for native commands in pipelines

Prerequisites

• Write a descriptive title.
• Make sure you are able to repro it on the latest released version
• Search the existing issues.
• Refer to the FAQ.
• Refer to Differences between Windows PowerShell 5.1 and PowerShell.

Steps to reproduce

I am trying to get the exit code of a native command, but the variable $LASTEXITCODE is not set. This happens only, if I pipe the output of the native command to a cmdlet.

The stripped down script, to reproduce this, is:

Set-StrictMode -Version:'3.0'
$local:ErrorActionPreference = 'Stop'

# Using cmd.exe here is only an example. Could be any native command.
$firstLine = cmd.exe /c 'echo hello & echo world & exit 42' | Select-Object -First 1
$firstLine
"The exit code of cmd.exe is ${LASTEXITCODE}"
'end'

I give this script the name temp.ps1. To run this script, I execute the following line in cmd.exe:

pwsh -NoProfile -File .\temp.ps1

Expected behavior

The expected output is:

hello
the exit code of cmd.exe is 42
end

Actual behavior

The actual output is:

hello
InvalidOperation: C:\Users\User\temp.ps1:7
Line |
   7 |  "The exit code of cmd.exe is ${LASTEXITCODE}"
     |                               ~~~~~~~~~~~~~~~
     | The variable '$LASTEXITCODE' cannot be retrieved because it has not been set.

Error details

Type        : System.Management.Automation.RuntimeException
ErrorRecord :
    Exception             :
        Type    : System.Management.Automation.ParentContainsErrorRecordException
        Message : The variable '$LASTEXITCODE' cannot be retrieved because it has not been set.
        HResult : -2146233087
    TargetObject          : LASTEXITCODE
    CategoryInfo          : InvalidOperation: (LASTEXITCODE:String) [], ParentContainsErrorRecordException
    FullyQualifiedErrorId : VariableIsUndefined
    InvocationInfo        :
        ScriptLineNumber : 7
        OffsetInLine     : 30
        HistoryId        : -1
        ScriptName       : C:\Users\User\temp.ps1
        Line             : "The exit code of cmd.exe is ${LASTEXITCODE}"

        PositionMessage  : At C:\Users\User\temp.ps1:7 char:30
                           + "The exit code of cmd.exe is ${LASTEXITCODE}"
                           +                              ~~~~~~~~~~~~~~~
        PSScriptRoot     : C:\Users\User
        PSCommandPath    : C:\Users\User\temp.ps1
        CommandOrigin    : Internal
    ScriptStackTrace      : at <ScriptBlock>, C:\Users\User\temp.ps1: line 7
                            at <ScriptBlock>, <No file>: line 1
TargetSite  :
    Name          : Invoke
    DeclaringType : System.Management.Automation.Runspaces.PipelineBase, System.Management.Automation, Version=7.3.4.500, Culture=neutral, PublicKeyToken=31bf3856ad364e35
    MemberType    : Method
    Module        : System.Management.Automation.dll
Message     : The variable '$LASTEXITCODE' cannot be retrieved because it has not been set.
Data        : System.Collections.ListDictionaryInternal
Source      : System.Management.Automation
HResult     : -2146233087
StackTrace  :
   at System.Management.Automation.Runspaces.PipelineBase.Invoke(IEnumerable input)
   at Microsoft.PowerShell.Executor.ExecuteCommandHelper(Pipeline tempPipeline, Exception& exceptionThrown, ExecutionOptions options)

Environment data

Name                           Value
----                           -----
PSVersion                      7.3.4
PSEdition                      Core
GitCommitId                    7.3.4
OS                             Microsoft Windows 10.0.19045
Platform                       Win32NT
PSCompatibleVersions           {1.0, 2.0, 3.0, 4.0…}
PSRemotingProtocolVersion      2.3
SerializationVersion           1.1.0.1
WSManStackVersion              3.0

and also

Name                           Value
----                           -----
PSVersion                      7.4.0-preview.3
PSEdition                      Core
GitCommitId                    7.4.0-preview.3
OS                             Microsoft Windows 10.0.19045
Platform                       Win32NT
PSCompatibleVersions           {1.0, 2.0, 3.0, 4.0…}
PSRemotingProtocolVersion      2.3
SerializationVersion           1.1.0.1
WSManStackVersion              3.0

Visuals

No response

[j0le]

I close this issue, because I see that the label “Issue-Question” was added. I interpret this to mean that the behaviour is as designed. Thanks again for your help.

[SeeminglyScience]

Select-Object -First 1 stops upstream commands after they have output one item, so cmd never hits the exit 42 part. If instead you force full execution of the command before piping like this:

(cmd.exe /c 'echo hello & echo world & exit 42') | Select-Object -First 1
$LASTEXITCODE

You will see what you expect