Sometime VS Code Debugger will Crash (PowerShell Extension) then odd things happen

[mjbvz]

From @swinster on January 9, 2017 23:27

• VSCode Version: Code 1.8.1 (ee428b0eead68bf0fb99ab5fdc4439be227b6281, 2016-12-19T14:49:23.350Z)
• OS Version: Windows_NT ia32 10.0.14986
• Extensions:

Extension	Author	Version
python	donjayamanne	0.5.5
beautify	HookyQR	0.7.3
rest-client	humao	0.11.4
PowerShell	ms-vscode	0.8.0

---

Steps to Reproduce:
Not sure if this is with VS Code or the PowerShell Extension.

Apologies for the woolly title and no step to replicate, but this is odd to say the least. Sometime, the VS Code debugger will hang when debugging a PS script. I can't restart the debugger, but eventually, after pressing the stop button several times it will stop. However, pressing play results in a blue scrolling time line above the debug pane, and when I click stop this time I retrieve an error saying the debugger has crashed.

Debug will not start until I have exited and restart Vs-code, but things to not stop there. I threw together a simple test of some functions in an attempt to replicate an odd behaviour I was seeing through a pipeline (running the through the VS PS Debugger), and even more odd behaviours were seen, such as the Process block of the second function in the pipeline running before the process block on the first function. In another script I was also seeing other pipeline functions fire (and of course fail) when simply stepping over a command in the current function (for example, a New-Item command to create a directory, or a '&' call out to another process. Even shutting down and restarting VS Code seem to do nothing.

Eventually I rebooted, but pretty sure this too too didn't do much either, until I change so code in For Each-Object loop, then eventually VS Code started behaving.

It was almost as it VS Code hadn't cleared some kind of internal stack and kept reverted to old path, or some such when the debugger was run.

Not sure if you can understand what I'm explaining, or if I can replicate, but this has been going on an off for a while. If there are file I can provide, let me know.

Copied from original issue: microsoft/vscode#18344

[mjbvz]

@swinster This sounds like an issue in the powershell extension so I've moved the issue over here.

Can you please provide a minimal powershell sample document and step by step guide to repo this issue.

Thanks

[swinster]

I will keep you posted on how to repro, but at the moment I'm clueless. Once i had got into this state, this was the following functions I ran:

function Test-Function-1 {
    [CmdletBinding()]
    param(
        [Parameter(
        ValueFromPipeline=$True,
        ValueFromPipelineByPropertyName=$True)]
        $testinput1)
    
    begin {
        Write-Host "Begin 1 - $testinput1"
    }
    
    process {
        Write-Host "Process 1 - $testinput1"
        if ( -Not (Test-Path "C:\TestDir")) {
            New-Item -Path "C:\TestDir" -ItemType Directory | out-null
        }
        $testinput1 = "Complete 1"
        return $testinput1

    }

    End {
        Write-Host "End 1 - $testinput1"
    }
} 

function Test-Function-2 {
    [CmdletBinding()]
    param(
        [Parameter(
        ValueFromPipeline=$True,
        ValueFromPipelineByPropertyName=$True)]
        $testinput2)
        
    begin {
        Write-Host "Begin 2 - $testinput2"
    }

    process {
        Write-Host "Process 2 - $testinput2"
        if ( -Not (Test-Path "C:\TestDir")){
            Write-Host "Folder doesnt exist"
        }
        $testinput2 = "Complete 2 - $testinput2"
        return $testinput2
    }

    End {
        Write-Host "End 2 - $testinput2"

    }
} 

$Start = @(1,2,3)
$Result = $Start | ForEach-Object {
   $_ | Test-Function-1 | Test-Function-2
} 
Write-Host $Result

I would stick a Brake-point at $Result, then step into the functions. I could see the the Begin block ran in Test-Function-1, then the Begin block in Test-Function-2. All good so far, however, as I continued to step through, I would expect that the debugger jump to process of Test-Function-1, but not, I carried right on into Test-Function-2 when the process block on Test-Function-2 was complete, it just seem to replicated this block, leaving Test-Function-1 Process until further down the line.

I should have screen cast this, as it make absolutely no sense to me.