Vscode-powershell: Read-host result is different from vscode and ISE

[SilverknightMel]

System Details

• Operating system name and version: Windows 2016
• VS Code version: 1.24.1
• PowerShell extension version: 1.7.0
• Output from $PSVersionTable:

Copy / paste the following commands into the PowerShell Integrated Console, and paste the output here:

code -v
$pseditor.EditorServicesVersion
code --list-extensions --show-versions
$PSVersionTable
Name                           Value
----                           -----
PSVersion                      5.1.14393.0
PSEdition                      Desktop
PSCompatibleVersions           {1.0, 2.0, 3.0, 4.0...}
BuildVersion                   10.0.14393.0
CLRVersion                     4.0.30319.42000
WSManStackVersion              3.0
PSRemotingProtocolVersion      2.3
SerializationVersion           1.1.0.1

Issue Description

I am experiencing a problem with null import value.
I have use a variable to accept a read-host which I just enter without typing any value.
With in vscode,
I have to use $a -eq $null to detect.
with in ISE
I have to use "" instead of $ull

Attached Logs

$a = Read-Host "type in value"
if ($a -eq $null){
    write-host "This is null"
}
if ($a -eq ""){
    write-host "This is double quote"
}

Follow the instructions in the README
about capturing and sending logs.

[TylerLeonhardt]

Hi @SilverknightMel! Thanks for this. Yes, I think we should fix this in the PSIC so it is consistent with everything else (ISE and normal console).

[rjmholt]

Given that this has been in VSCode for (I imagine) quite some time now, this is technically a breaking change. However, "" seems like a more appropriate return value if no value is entered.

[Halkcyon]

I'm not seeing the issue here? Read-Host should never return $null, either on the Integrated Console or from the powershell console. I tested this in both environments (1.7 extension, v5.1), and was unable to get Read-Host to return $null.

$a = Read-Host
> <ENTER>
$null -eq $a
> $false
'' -eq $a
> $true

[rjmholt]

Hmmmmmmm, yes, now that I've tested this, I can confirm the same behaviour that @TheIncorrigible1 is reporting.

Will close this. We can reopen later if the behaviour is reproducible on another platform. Might need a test on Windows Server 2016?

[KaMilleT]

I can reproduce this.

Name                           Value
----                           -----
PSVersion                      5.1.14393.3053
PSEdition                      Desktop
PSCompatibleVersions           {1.0, 2.0, 3.0, 4.0...}
BuildVersion                   10.0.14393.3053
CLRVersion                     4.0.30319.42000
WSManStackVersion              3.0
PSRemotingProtocolVersion      2.3
SerializationVersion           1.1.0.1

PowerShell Integrated Console in VSCode:

$a = Read-Host
> <ENTER>
$null -eq $a
False
'' -eq $a
True

$b = Read-Host -Prompt "Input"
Input: <ENTER>
$null -eq $b
True
'' -eq $b
False

PS-Console:

$a = Read-Host
> <ENTER>
$null -eq $a
False
'' -eq $a
True

$b = Read-Host -Prompt "Input"
Input: <ENTER>
$null -eq $b
False
'' -eq $b
True

The behaviour is different in VSCode when -Prompt is used while using Read-Host.

[TylerLeonhardt]

This is actually a dupe of https://github.com/PowerShell/vscode-powershell/issues/1790 and I have a PR out fixing it.