Wait-Process after Stop-Process to processes on another user often blanks processes fields #27867

$ErrorActionPreference="stop"


$user=New-LocalUser -NoPassword test_waitprocess_bug
try{
    $pass=ConvertTo-SecureString -AsPlainText -Force "wowverysecure"
    Set-LocalUser $user -Password $pass


    function start_procs{
        1..10 | ForEach-Object {
            [System.Diagnostics.Process]::Start((New-Object System.Diagnostics.ProcessStartInfo winver -Property @{
                UserName=$user;
                Password=$pass;
                UseShellExecute=$false;
                WorkingDirectory="C:\"
            }))
        } | Out-Null
    }

    function test{
        param(
            [switch]$expected_behavior
        )

        $procs=Get-Process -IncludeUserName | Where-Object UserName -EQ "${env:COMPUTERNAME}\$user"
        Stop-Process -Force $procs

        if($expected_behavior){
            $procs | ForEach-Object {$_.WaitForExit()}
        }else{
            $procs | Wait-Process
        }

        $procs
    }


    start_procs
    $procs=test
    Write-Output "Actual bad behavior:"
    Write-Output $procs

    Write-Output ""

    start_procs
    $procs=test -expected_behavior
    Write-Output "Expected good behavior:"
    Write-Output $procs
}finally{
    Remove-LocalUser $user
}

Name                           Value
----                           -----
PSVersion                      7.7.0-preview.3
PSEdition                      Core
GitCommitId                    7.7.0-preview.3
OS                             Microsoft Windows 10.0.26200
Platform                       Win32NT
PSCompatibleVersions           {1.0, 2.0, 3.0, 4.0…}
PSRemotingProtocolVersion      2.4
SerializationVersion           1.1.0.1
WSManStackVersion              3.0