Test-DscConfiguration not returning value in Powershell Integrated Console

[marvelcz89]

Issue Description

Invoking Test-DscConfiguration does not return value when invoked for the first time in session in Powershell Integrated Console and also a few seconds afterwards.
The functionality is restored after several seconds after first Test-DscConfiguration call but the initial queries are already faulty..
Here is the screenshot of the behavior: https://gyazo.com/4e3696d65e3e0de34cb2cdf6a9680bf6

No faults when used in regular VS Code terminal, ISE, or directly invoking the .EXE

I was able to replicate the issue on a freshly installed VM both W10 1909 and WS 2016 1909 + VS Code 1.49 and Powershell Extension 2020.6.0 for PS versions 5.1 and 7.0.3

EDIT1: Additional information

1. Saving to a variable does not provide result: https://gyazo.com/8564392a43a0fb6d977da0cb5d14cef1
2. Invoking with -Verbose works consistently, might be related why i can not reproduce with Diagnostic log mode: https://gyazo.com/eceda3d54e84ce2ca9076f5269a3a321
3. Invoking with -Verbose and redirecting verbose output does not work as workaround: https://gyazo.com/f82b2db98a2b81d37821b543a1cf3d0e

EDIT2: Additional information
I have added additional behaviour examples in posts below.

Workaround

I added following configuration to avoid using Integrated console:

1. "powershell.integratedConsole.showOnStartup": false
2. "terminal.integrated.shell.windows": "C:\WINDOWS\System32\WindowsPowerShell\v1.0\powershell.exe"
   or
3. "terminal.integrated.shell.windows": "C:\Program Files\PowerShell\7\pwsh.exe"

Attached Logs

The issue not occuring with Diagnostics mode for some reason :(

Environment Information

Visual Studio Code

Name	Version
Operating System	Windows_NT x64 10.0.18363
VSCode	1.49.0
PowerShell Extension Version	2020.6.0

PowerShell Information

Name	Value
PSVersion	7.0.3
PSEdition	Core
GitCommitId	7.0.3
OS	Microsoft Windows 10.0.18363
Platform	Win32NT
PSCompatibleVersions	1.0 2.0 3.0 4.0 5.0 5.1.10032.0 6.0.0 6.1.0 6.2.0 7.0.3
PSRemotingProtocolVersion	2.3
SerializationVersion	1.1.0.1
WSManStackVersion	3.0

Visual Studio Code Extensions

Visual Studio Code Extensions(Click to Expand)

Extension	Author	Version
bracket-pair-colorizer-2	CoenraadS	0.2.0
gc-excelviewer	GrapeCity	3.0.40
gitlens	eamodio	10.2.2
powershell	ms-vscode	2020.6.0
rainbow-csv	mechatroner	1.7.1
reg	ionutvmi	1.0.1
team	ms-vsts	1.161.0
vscode-icons	vscode-icons-team	10.2.0
xml	DotJoshJohnson	2.5.1

[SydneyhSmith]

@marvelcz89 thanks for the info-- I wonder if you assign it to a variable if you are able to retrieve a result i.e. maybe the command is being returned but not printed properly?
Also would be great if this also occurs with any other command ex. $true

[marvelcz89]

@SydneyhSmith I have added some additional information to EDIT1.

[SydneyhSmith]

Thanks @marvelcz89 that is very helpful-- it would be great if you tried this one again with a slight variation: Saving to a variable does not provide result: https://gyazo.com/8564392a43a0fb6d977da0cb5d14cef1
Could you please run the first line again, and then after that just run $test for the next 2-4 times.

$test = Test-DSCConfiguration 
$test 

[marvelcz89]

Hello @SydneyhSmith
Wall of text incomming with more examples. Every example was executed in fresh powershell integrated terminal, and multiple times to ensure consistency. The examples below were done in Powershell 5.1.18362.145 i am not including tests from PS Core 7.0 where i found the same issue as well.

Additional example 1 code:
$Test = Test-DscConfiguration
and then
$Test

Additional example 1 result:
Returned value correctly: https://gyazo.com/88242a1bc34210ff944e910a0748b5f6

Additional example 2 code:

$Test = Test-DscConfiguration 
$Test

Additional example 2 result:
Expected result is TRUE but nothing is returned: https://gyazo.com/f51f1d9543db83106f69e2a0a6f03a76

Additional example 3 code:

$Test = Test-DscConfiguration
$Test
$Test
$Test
$Test
$Test

Additional example 3 result:
During about a dozen of invocations all in fresh terminal the first two $Test calls added a blank line.
Re-invoking in same session fixed the issue: https://gyazo.com/f28740e918f6410dfa4305ffe4526d66

Additional example 4 code:
Here i was thinking, if first Test-DscConfiguration cmdlet calls in terminal sessions return nothing, aka $null, the follwing should print something at least ...

if (Test-DscConfiguration) {
   Write-Host "OK"
}
else {
   Write-Host "RIP"
}

Additional example 4 result:
Nothing was printed in console: https://gyazo.com/70f2c0805dfb4e437e5fc3d812d7510c

Additional example 5 code:
Since example 4 did not do anything, the following should not work either right?

$Result = "NothingYet"
if (Test-DscConfiguration) {
    $Result = "OK"
}
else {
    $Result = "RIP"
}
Write-Host $Result

Additional example 5 result:
However the script worked as expected unlike example 4: https://gyazo.com/95ce1fc8506dd3497471caf239a1aebc

[SydneyhSmith]

@marvelcz89 thanks so much for taking the time to test all these examples, they are very helpful for us! I do want to confirm that these were all done using F8 (rather than being pasted into the terminal), is that correct?
Looks like this issue will be resolved by PowerShell/PowerShellEditorServices#1295

[marvelcz89]

@SydneyhSmith The issue occurs in F8 selective execution, F5 script execution, and also when manually typing and executing in PS integrated console.
Regarding the mentioned issue #1295, does that mean that DSC is not yet supported by the Powershell extension for VS Code?
When i implement the workaround as described in the 1st post, it resolves the invocation issue but the intelisense is incomplete as it still uses its hidden integrated console as source. Or can this be resolved by additional reconfiguration?

Many thanks for information!

[rjmholt]

DSC is supported, but is currently buggy due to deeper issues in the extension as described in #2745. Because DSC features only get used by some users (compared to features like intellisense), we don't hear about bugs in it as often as we probably should.

I don't know if you can fix the intellisense issue with reconfiguration (the hidden integrated console you describe is just the state of the PowerShell process -- without that, you have no intellisense). We're working on fixing the intellisense issue, but we're not quite there yet.